tag:theconversation.com,2011:/id/topics/vaccines-690/articlesVaccines – The Conversation2024-03-21T20:24:31Ztag:theconversation.com,2011:article/2262052024-03-21T20:24:31Z2024-03-21T20:24:31ZMeasles is highly contagious, but vaccine-preventable: A primer on recent outbreaks, transmission, symptoms and complications, including ‘immune amnesia’<figure><img src="https://images.theconversation.com/files/583049/original/file-20240320-16-lkngkh.jpg?ixlib=rb-1.1.0&rect=0%2C135%2C3962%2C2913&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A measles virus particle. Measles is one of the most contagious pathogens known.</span> <span class="attribution"><span class="source">(CDC and NIAID)</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>Canada is seeing a resurgence of measles, with cases in the first quarter of 2024 already far surpassing the total for all of 2023. There were <a href="https://www.canada.ca/en/public-health/services/publications/diseases-conditions/measles-rubella-surveillance/2023/week-52.html">12 cases last year</a>, and more than three times that number so far in 2024, with 38 reported as of March 19. </p>
<p>Most of these cases (28) <a href="https://www.quebec.ca/en/health/health-issues/a-z/measles/measles-outbreak">are in Québec</a>, and <a href="https://www.publichealthontario.ca/-/media/Documents/M/24/measles-ontario-epi-summary.pdf?rev=c082f5ae0c6c446f9624d47b7e3c8535&sc_lang=en">eight are in Ontario</a>, while <a href="https://www.saskhealthauthority.ca/news-events/news/measles-exposure-risk-saskatoon">Saskatchewan</a> and <a href="https://news.gov.bc.ca/releases/2024HLTH0026-000274">British Columbia</a> have each reported one case. </p>
<p>As an immunologist with a focus on host-microbe interactions and antiviral immunity, I have been following recent measles outbreaks. </p>
<h2>Symptoms and complications</h2>
<p>Measles (also known as rubeola) is a serious but vaccine-preventable disease caused by an RNA virus of the family <a href="https://www.britannica.com/science/paramyxovirus-virus-family">Paramyxoviridae</a>. </p>
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<a href="https://images.theconversation.com/files/583046/original/file-20240320-24-qx59sq.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A child seen from behind with a red rash all over his skin" src="https://images.theconversation.com/files/583046/original/file-20240320-24-qx59sq.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/583046/original/file-20240320-24-qx59sq.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=720&fit=crop&dpr=1 600w, https://images.theconversation.com/files/583046/original/file-20240320-24-qx59sq.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=720&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/583046/original/file-20240320-24-qx59sq.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=720&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/583046/original/file-20240320-24-qx59sq.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=905&fit=crop&dpr=1 754w, https://images.theconversation.com/files/583046/original/file-20240320-24-qx59sq.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=905&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/583046/original/file-20240320-24-qx59sq.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=905&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Measles rash appears on the face before spreading downward to other areas of the body.</span>
<span class="attribution"><span class="source">(U.S. Centers for Disease Control)</span></span>
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<p>Measles usually begins with fever, runny nose, conjunctivitis (red watery eyes), sore throat and coughing. These can be initially mistaken for common cold or flu.</p>
<p>However, these non-specific signs and symptoms are typically followed by clinical manifestations that are characteristic of measles. These include Koplik spots (tiny white specks with bluish-white centres in the inner lining of the cheeks), and subsequently a <a href="https://www.cdc.gov/measles/symptoms/signs-symptoms.html">measles rash</a> appearing on the face before spreading downward to other areas of the body.</p>
<p>In most cases, measles resolves on its own. However, <a href="https://www.mayoclinic.org/diseases-conditions/measles/symptoms-causes/syc-20374857">severe complications</a> may arise, especially in immunocompromised individuals. <a href="https://www.cdc.gov/globalhealth/measles/about/index.html">Complications</a> can include pneumonia, encephalitis (brain inflammation and swelling), blindness, deafness and permanent neurological consequences. When measles occurs during pregnancy, it can result in miscarriage, premature labour, stillbirth, birth defects or even fetal death. The most severe cases of measles can be fatal. </p>
<p>Also of note, infection with the measles virus can weaken the immune system for months or years, increasing the risk of infections with a wide range of microbes. While measles-associated immunosuppression has been documented for decades, we are only beginning to decipher its underlying mechanisms. For example, a phenomenon called “<a href="https://doi.org/10.1038/s41467-018-07515-0">immune amnesia</a>” is thought to contribute, at least partially, to unrelated infections in the aftermath of measles.</p>
<h2>What is immune amnesia?</h2>
<p>The naturally occurring (wild-type) strains of measles virus can target, infect and kill memory B and T lymphocytes, which are instrumental to antimicrobial defence. This is because one of the three measles virus receptors, called CD150, happens to be abundantly present on the surface of these lymphocytes.</p>
<p>Long-lived memory cells, which accumulate as a result of immunizations and infections over time, remain in a poised state to mount rapid and rigorous recall responses when we re-encounter microbes. B cells orchestrate the production of antibodies that neutralize extracellular microbes, and T cells work to destroy infected cells. Therefore, when people lose their precious memory cells to measles, the immune system is set back to a default mode, as if it has never seen any microbes or vaccines in the past.</p>
<p>To add insult to injury, <a href="https://doi.org/10.1093/infdis/jiaa407">measles virus may also eliminate “memory-like” innate T cells</a>, which also express CD150, thus removing yet another potent weapon from our antimicrobial arsenal. Therefore, collectively, the ability of measles virus to find and kill memory and memory-like lymphocytes can lead to adaptive and <a href="https://doi.org/10.1371/journal.ppat.1009071">innate immune amnesia</a>, rendering a measles patient or survivor prone to many opportunistic infections.</p>
<h2>How does measles spread and how contagious is it?</h2>
<figure class="align-right ">
<img alt="microscopic image of a virus" src="https://images.theconversation.com/files/583047/original/file-20240320-20-nv4olv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/583047/original/file-20240320-20-nv4olv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=459&fit=crop&dpr=1 600w, https://images.theconversation.com/files/583047/original/file-20240320-20-nv4olv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=459&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/583047/original/file-20240320-20-nv4olv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=459&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/583047/original/file-20240320-20-nv4olv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=577&fit=crop&dpr=1 754w, https://images.theconversation.com/files/583047/original/file-20240320-20-nv4olv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=577&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/583047/original/file-20240320-20-nv4olv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=577&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Microscopic view of a measles virus particle (red).</span>
<span class="attribution"><span class="source">(CDC and NIAID)</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
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<p>Measles virus spreads easily through airborne droplets released by infected people when they breathe, talk, laugh, cough or sneeze. In addition, measles virus infectious particles can remain active in the air and on contaminated surfaces for up to two hours.</p>
<p>Measles virus is one of the most contagious respiratory pathogens known, with <a href="https://doi.org/10.1016/S1473-3099(17)30307-9">each person with measles passing on their infection to 12 to 18 other people</a> in a susceptible population. Measles virus is more transmissible than influenza viruses and SARS-CoV-2 variants.</p>
<h2>How effective are measles vaccines?</h2>
<p>Measles vaccines are safe, affordable and extremely effective. According to the World Health Organization (WHO), <a href="https://www.who.int/news-room/fact-sheets/detail/measles">measles claimed 2.6 million lives each year before 1963</a> when a measles vaccine became available. Since then, widespread immunization programs have saved millions of lives, including an estimated 56 million just between 2000 and 2021.</p>
<p>Measles vaccines contain a live measles virus strain that has been attenuated so that it does not inflict harm; yet, it is sufficient to generate protective immune responses. </p>
<p>The measles-mumps-rubella (MMR) vaccine or the measles-mumps-rubella-varicella (MMRV) vaccine is routinely administered to children in <a href="https://www.canada.ca/en/public-health/services/diseases/measles/health-professionals-measles.html">two doses</a>, with a first dose being given after the first birthday, typically between 12-15 months of age, followed by a booster dose recommended after 18 months of age and before attending school. This should afford lifelong protection against measles in most people. </p>
<p>According to the United States Centers for Disease Control and Prevention (CDC), one and two doses of the MMR vaccine are <a href="https://www.cdc.gov/vaccines/vpd/mmr/public/index.html">93 per cent and 97 per cent effective</a> in preventing measles, respectively. </p>
<p>Teens and adults should also <a href="https://www.canada.ca/en/public-health/services/publications/healthy-living/canadian-immunization-guide-part-4-active-vaccines/page-12-measles-vaccine.html#">remain up to date with regard to measles immunization</a> since measles can affect anyone. There are blood tests that can be ordered by health-care providers to determine immunity to measles. </p>
<p>The MMR vaccine can be <a href="https://www.canada.ca/en/public-health/services/publications/healthy-living/canadian-immunization-guide-part-4-active-vaccines/page-12-measles-vaccine.html#">given at any time</a> during one’s lifespan, but the MMRV vaccine is authorized in Canada only between one and 13 years of age.</p>
<h2>Why are measles cases returning?</h2>
<p>Recent years have witnessed a rise in measles outbreaks within and outside Canada. This is primarily due to an alarming decline in measles vaccination caused by <a href="https://theconversation.com/measles-global-increase-in-cases-likely-driven-by-covid-pandemic-182250">delayed childhood immunizations amid COVID-19</a> lockdowns, vaccine hesitancy <a href="https://theconversation.com/measles-outbreak-why-are-anti-vaxxers-risking-a-public-health-crisis-116334">creating vulnerable societal pockets</a>, anti-vaccine sentiments and <a href="https://time.com/6564694/measles-antivaccine-misinformation/">digital misinformation</a> spread through online social media, and the resumption of global travel post-COVID.</p>
<p>Measles outbreaks occur soon after <a href="https://doi.org/10.1001/jama.2020.20895">herd immunity</a> is compromised. Herd immunity is achieved when an adequately large proportion of a population becomes immune to a specific pathogen through prior infections or vaccination. As a result, the probability of an infectious case encountering a susceptible person drops dramatically. </p>
<p>For measles, the necessary <a href="https://www.who.int/news/item/23-11-2022-nearly-40-million-children-are-dangerously-susceptible-to-growing-measles-threat">threshold for herd immunity is 95 per cent</a>. This means when 95 per cent of people in a population are immune, the remaining five per cent (including newborns, unvaccinated or undervaccinated children and immunodeficient people who cannot receive a measles vaccine) are also indirectly protected since the risk of measles virus transmission is significantly minimized.</p>
<p>By receiving two doses of a measles vaccine, one protects not only themselves but also the vulnerable members of their community. The only way to avoid measles and its serious complications, including proneness to a broad spectrum of unrelated infections, is to vaccinate widely, to engage those who are hesitant to have their children immunized in a respectful dialogue, and to educate the public regarding the unparalleled benefits of measles vaccines.</p>
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Read more:
<a href="https://theconversation.com/how-better-conversations-can-help-reduce-vaccine-hesitancy-for-covid-19-and-other-shots-159321">How better conversations can help reduce vaccine hesitancy for COVID-19 and other shots</a>
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<p>It is also crucial to isolate infected individuals for four days after the appearance of a measles rash to prevent measles virus transmission to others.</p>
<p>In Canada, measles has been <a href="https://www.canada.ca/en/public-health/services/diseases/measles/surveillance-measles.html">a nationally notifiable disease</a> since 1924 (except between 1959 and 1968), and the Canadian Measles and Rubella Surveillance System (CMRSS) ensures the weekly collection of measles data from every province and territory, including zero report submissions.</p><img src="https://counter.theconversation.com/content/226205/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mansour Haeryfar does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Canada is seeing a surge in measles cases. Find out what measles is, why it’s returning to Canada, and how people can protect themselves and others.Mansour Haeryfar, Professor of Immunology, Western UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2253982024-03-14T09:58:53Z2024-03-14T09:58:53ZDengue: Brazilian single-dose vaccine could help turn tide in the fight against fever<p>Dengue, caused by the virus transmitted by the bite of the female <em>Aedes aegypti</em> mosquito and, to a lesser extent, the <em>Aedes albopictus</em> mosquito, is an acute illness characterized mainly by high fever, body aches and redness of the skin. </p>
<p>A small fraction of those displaying <a href="https://www.cdc.gov/dengue/symptoms/index.html">symptoms</a> can experience a worsening disease at the end of the first week. These cases, classified as dengue with warning signs and severe dengue by the World Health Organisation (WHO), are the most worrying, leading to significant morbidity and mortality in tropical and subtropical regions worldwide.</p>
<p>In dengue with warning signs, in addition to the classic symptoms, there may be small amounts of blood on the mucous membranes, haematomas, abdominal pain, vomiting, dehydration, restlessness, dizziness, excessive tiredness and drowsiness.</p>
<p>Severe dengue is a result of a greater systemic inflammatory reaction, which alters blood clotting and leads to fluid loss. The consequences can include intense bleeding and a sudden drop in blood pressure, which are responsible for the shock associated with dengue fever, the main cause of death. </p>
<p>The number of people with severe disease is small compared to the total incidence of the disease. Of the three million confirmed cases of dengue in Brazil in 2023, only 0.1% had the worst symptoms of the disease, according to the WHO.</p>
<p>However, as <a href="https://www.paho.org/en/topics/dengue">the number of cases continues to rise in 2024</a>, this small percentage exerts a big impact, with even more pressure on health services. Brazil recorded more than a million suspected cases and dozens of deaths from dengue fever in 2024 up to the beginning of March 2024, according to the Ministry of Health, a quite significant increase compared to the same period in 2023.</p>
<p>This situation is part of a <a href="https://www.who.int/emergencies/disease-outbreak-news/item/2023-DON498">major global increase</a> in the disease, which has already registered five million cases in 129 countries. </p>
<h2>The main victims</h2>
<p>Young children and older people can find it more difficult to cope with severe infections due to immunity issues. Another important factor related to severe dengue is that it is more frequent in the second and third infections. As there are four viruses causing dengue worldwide, DENV-1, DENV-2, DENV-3 and DENV-4, a given person can be infected four times.</p>
<p>The chance of developing the most serious symptoms in the first infection is low but increases in the second and third, especially among those in people with other illnesses. This appears to be because antibodies produced by the body against one dengue virus type facilitate the entry of a second dengue virus, which is not completely neutralized. It would seem these enter the cells more easily and multiply more quickly. This mechanism is known as “antibody-dependent enhancement”. With the number of cases rising, the phenomenon needs special attention.</p>
<p>To avoid this situation, it is preferable to have protection against all four types of dengue viruses. In times of cyclical outbreaks, we can no longer remain uncovered. It will then be up to vaccination to help us achieve this goal.</p>
<h2>Single-dose vaccine</h2>
<p>A dengue vaccine must be able to elicit high efficacy against the four viruses, be safe and be able to, ultimately, help contain the virus spread. In other words, it must induce protection against at least three and preferably to all four dengue viruses at the same time, as if it were four vaccines in one. </p>
<p>Offering this possibility in less time, i.e. in a single dose, could be the game changer for guaranteeing complete protection more quickly, potentially putting a stop onto outbreaks, and protecting those who need it most.</p>
<p>The Butantan Institute has been working on the development of a dengue vaccine since the late 1990s. <a href="https://www.nejm.org/doi/full/10.1056/NEJMoa2301790">We recently published</a> the primary phase 3 results of the vaccine candidate in The New England Journal of Medicine.</p>
<p>With just one injection, it provides good protection in a very elastic age range, from two to 60 incomplete years, according to the published results. It also has the differential of being able to be applied to those who have or have not already been infected by the dengue virus.</p>
<p>Protection was observed in all age groups, with 90% in adults aged 18 to 59, 77.8% in those aged seven to 17 and 80.1% in children aged two to six. The analysis of the effectiveness of the immunogen was carried out over two years with just under 17,000 volunteers in 16 research centers. The study is in its final phase and will complete in June 2024.</p>
<p>The next step will be to finalise the dossier with all the study information to apply for registration at Brazil’s National Health Surveillance Agency (Anvisa) by the second half of 2024.</p>
<p>At a time when dengue is advancing worldwide due to climate change, the arrival of a new single-dose vaccine to prevent epidemics and deaths could be a key weapon in the fight against dengue.</p><img src="https://counter.theconversation.com/content/225398/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Esper Georges Kallás não presta consultoria, trabalha, possui ações ou recebe financiamento de qualquer empresa ou organização que poderia se beneficiar com a publicação deste artigo e não revelou nenhum vínculo relevante além de seu cargo acadêmico.</span></em></p>A new single dose vaccine is expected to be registered with the country’s national health agency by the second half of this year.Esper Georges Kallás, Diretor do Instituto Butantan e Professor Titular do Departamento de Moléstias Infecciosas e Parasitárias, Faculdade de Medicina da USP (FMUSP)Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2174332024-03-11T12:28:43Z2024-03-11T12:28:43ZVaccine-skeptical mothers say bad health care experiences made them distrust the medical system<figure><img src="https://images.theconversation.com/files/580008/original/file-20240305-18-5fkuf2.jpg?ixlib=rb-1.1.0&rect=86%2C28%2C4623%2C3168&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Women's own negative medical experiences influence their vaccine decisions for their kids.</span> <span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/VirusOutbreakPediatricVaccines/9249589410f742d586eeff3122190438/photo?boardId=71cbe30c136941ba87c7b57dabd12ef2&st=boards&mediaType=audio,photo,video,graphic&sortBy=&dateRange=Anytime&totalCount=2&currentItemNo=0">AP Photo/Ted S. Warren</a></span></figcaption></figure><p>Why would a mother reject safe, potentially lifesaving vaccines for her child?</p>
<p><a href="https://www.salon.com/2019/02/10/the-unsubtle-sexism-of-the-anti-vax-mom-meme/">Popular writing on vaccine skepticism</a> often denigrates white and middle-class mothers who reject some or all recommended vaccines <a href="https://www.washingtonpost.com/opinions/2021/07/08/right-wing-anti-vaccine-hysteria-is-increasing-well-all-pay-price/">as hysterical</a>, <a href="https://doi.org/10.1080/09589236.2022.2069088">misinformed, zealous</a> <a href="https://www.canberra.edu.au/uncover/news-archive/2022/april/targetting-mothers-anti-vaxxers-insidious-strategies">or ignorant</a>. <a href="https://www.nytimes.com/2022/05/25/magazine/anti-vaccine-movement.html">Mainstream media</a> <a href="https://www.vanityfair.com/news/2021/07/anthony-fauci-coronavirus-vaccine-polio-measles">and medical providers</a> increasingly dismiss vaccine refusal as a hallmark of American fringe ideology, <a href="https://www.nytimes.com/2021/08/31/opinion/anti-vaccine-movement.html">far-right radicalization or anti-intellectualism</a>.</p>
<p>But vaccine skepticism, and the broader medical mistrust and far-reaching anxieties it reflects, is not just a fringe position.</p>
<p>Pediatric vaccination rates had already <a href="https://www.cedars-sinai.org/newsroom/2019-the-year-of-vaccine-preventable-diseases/">fallen sharply before the COVID-19 pandemic</a>, ushering in the return of measles, mumps and chickenpox to the U.S. in 2019. Four years after the pandemic’s onset, a growing number of Americans doubt the safety, efficacy and necessity of routine vaccines. Childhood vaccination rates have declined substantially across the U.S., which public health officials attribute to a <a href="https://apnews.com/article/health-immunizations-children-measles-acba3eb975fdfcd41732ed87511387f2">“spillover” effect</a> from pandemic-related vaccine skepticism and blame for the <a href="https://www.nytimes.com/news-event/measles-outbreak">recent measles outbreak</a>. Almost half of American mothers <a href="https://www.pewresearch.org/science/2023/05/16/americans-largely-positive-views-of-childhood-vaccines-hold-steady/">rated the risk of side effects from the MMR vaccine</a> as medium or high in a 2023 survey by Pew Research. </p>
<p>Recommended vaccines go through rigorous testing and evaluation, and the most infamous charges of vaccine-induced injury <a href="https://www.jstor.org/stable/25766651">have been thoroughly debunked</a>. How do so many mothers – primary caregivers and health care decision-makers for their families – become wary of U.S. health care and one of its most proven preventive technologies?</p>
<p>I’m a cultural anthropologist who <a href="https://scholar.google.com/citations?user=nzIMuB8AAAAJ&hl=en&oi=ao">studies the ways feelings and beliefs circulate in American society</a>. To investigate what’s behind mothers’ vaccine skepticism, <a href="https://doi.org/10.1111/maq.12764">I interviewed vaccine-skeptical mothers</a> about their perceptions of existing and novel vaccines. What they told me complicates sweeping and overly simplified portrayals of their misgivings by pointing to the U.S. health care system itself. The medical system’s failures and harms against women gave rise to their pervasive vaccine skepticism and generalized medical mistrust.</p>
<h2>The seeds of women’s skepticism</h2>
<p>I conducted <a href="https://doi.org/10.1111/maq.12764">this ethnographic research</a> in Oregon from 2020 to 2021 with predominantly white mothers between the ages of 25 and 60. My findings reveal new insights about the origins of vaccine skepticism among this demographic. These women traced their distrust of vaccines, and of U.S. health care more generally, to ongoing and repeated instances of medical harm they experienced from childhood through childbirth.</p>
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<a href="https://images.theconversation.com/files/580511/original/file-20240307-28-wlrbi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="girl sitting on exam table faces a doctor viewer can see from behind" src="https://images.theconversation.com/files/580511/original/file-20240307-28-wlrbi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/580511/original/file-20240307-28-wlrbi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/580511/original/file-20240307-28-wlrbi.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/580511/original/file-20240307-28-wlrbi.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/580511/original/file-20240307-28-wlrbi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/580511/original/file-20240307-28-wlrbi.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/580511/original/file-20240307-28-wlrbi.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">A woman’s own childhood mistreatment by a doctor can shape her health care decisions for the next generation.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/little-girl-at-a-medical-appointment-royalty-free-image/1670275219">FatCamera/E+ via Getty Images</a></span>
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<p>As young girls in medical offices, they were touched without consent, yelled at, disbelieved or threatened. One mother, Susan, recalled her pediatrician abruptly lying her down and performing a rectal exam without her consent at the age of 12. Another mother, Luna, shared how a pediatrician once threatened to have her institutionalized when she voiced anxiety at a routine physical.</p>
<p>As women giving birth, they often felt managed, pressured or discounted. One mother, Meryl, told me, “I felt like I was coerced under distress into Pitocin and induction” during labor. Another mother, Hallie, shared, “I really battled with my provider” throughout the childbirth experience. </p>
<p>Together with the convoluted bureaucracy of for-profit health care, experiences of medical harm contributed to “one million little touch points of information,” in one mother’s phrase, that underscored the untrustworthiness and harmful effects of U.S. health care writ large.</p>
<h2>A system that doesn’t serve them</h2>
<p>Many mothers I interviewed rejected the premise that public health entities such as the Centers for Disease Control and Prevention and the Food and Drug Administration had their children’s best interests at heart. Instead, they tied childhood vaccination and the more recent development of COVID-19 vaccines to a bloated pharmaceutical industry and for-profit health care model. As one mother explained, “The FDA is not looking out for our health. They’re looking out for their wealth.”</p>
<p>After ongoing negative medical encounters, the women I interviewed lost trust not only in providers but the medical system. Frustrating experiences prompted them to “do their own research” in the name of bodily autonomy. Such research often included books, articles and podcasts deeply critical of vaccines, public health care and drug companies.</p>
<p>These materials, which have proliferated since 2020, cast light on past vaccine trials gone awry, broader histories of medical harm and abuse, the rapid growth of the recommended vaccine schedule in the late 20th century and the massive profits reaped from drug development and for-profit health care. They confirmed and hardened women’s suspicions about U.S. health care.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/580514/original/file-20240307-23-p10d28.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="hands point to a handwritten vaccination record" src="https://images.theconversation.com/files/580514/original/file-20240307-23-p10d28.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/580514/original/file-20240307-23-p10d28.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=446&fit=crop&dpr=1 600w, https://images.theconversation.com/files/580514/original/file-20240307-23-p10d28.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=446&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/580514/original/file-20240307-23-p10d28.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=446&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/580514/original/file-20240307-23-p10d28.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=561&fit=crop&dpr=1 754w, https://images.theconversation.com/files/580514/original/file-20240307-23-p10d28.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=561&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/580514/original/file-20240307-23-p10d28.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=561&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">The number of recommended childhood vaccines has increased over time.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/tom-lyons-dir-of-communications-of-the-boston-public-health-news-photo/1340505911">Mike Adaskaveg/MediaNews Group/Boston Herald via Getty Images</a></span>
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<p>The stories these women told me add nuance to existing academic research into vaccine skepticism. Most studies have considered vaccine skepticism among <a href="https://doi.org/10.1111/maq.12214">primarily white and middle-class parents</a> to be <a href="https://doi.org/10.1177/0891243214532711">an outgrowth of today’s neoliberal parenting</a> and <a href="https://nyupress.org/9781479874835/calling-the-shots/">intensive mothering</a>. Researchers have theorized vaccine skepticism among white and well-off mothers to be an outcome of <a href="https://doi.org/10.1080/14797585.2021.1886425">consumer health care</a> and its emphasis on <a href="https://doi.org/10.1080/01459740.2016.1145219">individual choice</a> and <a href="https://doi.org/10.1016/j.socscimed.2007.04.023">risk reduction</a>. Other researchers highlight vaccine skepticism as a collective identity that can provide mothers with a <a href="https://doi.org/10.14506/ca31.3.04">sense of belonging</a>.</p>
<h2>Seeing medical care as a threat to health</h2>
<p>The perceptions mothers shared are far from isolated or fringe, and they are not unreasonable. Rather, they represent a growing population of Americans who hold the pervasive belief that U.S. health care harms more than it helps.</p>
<p>Data suggests that the number of Americans harmed in the course of treatment remains high, with <a href="https://www.healthsystemtracker.org/chart-collection/quality-u-s-healthcare-system-compare-countries/#patient-safety">incidents of medical error in the U.S.</a> outnumbering those in peer countries, despite more money being spent per capita on health care. <a href="https://www.hopkinsmedicine.org/news/newsroom/news-releases/2023/07/report-highlights-public-health-impact-of-serious-harms-from-diagnostic-error-in-us#:%7E:text=The%20overall%20average%20error%20rate,missed%20in%2017.5%25%20of%20cases.">One 2023 study</a> found that diagnostic error, one kind of medical error, accounted for 371,000 deaths and 424,000 permanent disabilities among Americans every year. </p>
<p>Studies reveal particularly high rates of medical error in the treatment of <a href="https://www.bu.edu/bulawreview/files/2022/03/JEAN-PIERRE.pdf">vulnerable communities</a>, including <a href="https://doi.org/10.1186/s12939-018-0828-7">women, people of color</a>, <a href="https://doi.org/10.1377/hlthaff.2020.01452">disabled</a>, <a href="https://doi.org/10.1371/journal.pone.0166762">poor</a>, <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8861755/">LGBTQ+ and gender-nonconforming individuals</a> and <a href="https://doi.org/10.3111/13696998.2013.848210">the elderly</a>. The number of U.S. women who have <a href="https://doi.org/10.1001/jama.2023.9043">died because of pregnancy-related causes</a> has increased substantially in recent years, with maternal death rates doubling between 1999 and 2019.</p>
<p>The prevalence of medical harm points to the relevance of <a href="https://www.britannica.com/biography/Ivan-Illich">philosopher Ivan Illich</a>’s manifesto against the “disease of medical progress.” In his 1982 book “<a href="https://search.worldcat.org/title/8493694">Medical Nemesis</a>,” he insisted that rather than being incidental, harm flows inevitably from the structure of institutionalized and for-profit health care itself. Illich wrote, “The medical establishment has become a major threat to health,” and has created its own “epidemic” of iatrogenic illness – that is, illness caused by a physician or the health care system itself.</p>
<p>Four decades later, <a href="https://doi.org/10.1056/NEJMp1407373">medical mistrust among Americans</a> remains alarmingly high. Only 23% of Americans express high confidence in the medical system. The United States ranks 24th out of 29 peer high-income countries for the level of public trust in medical providers.</p>
<p>For people like the mothers I interviewed, who have experienced real or perceived harm at the hands of medical providers; have felt belittled, dismissed or disbelieved in a doctor’s office; or spent countless hours fighting to pay for, understand or use health benefits, skepticism and distrust are rational responses to lived experience. These attitudes do not emerge solely from ignorance, conspiracy thinking, far-right extremism or hysteria, but rather the historical and ongoing harms endemic to the U.S. health care system itself.</p><img src="https://counter.theconversation.com/content/217433/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Johanna Richlin does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Vaccine skepticism, and the broader medical mistrust and far-reaching anxieties it reflects, is not just a fringe position in the 21st century.Johanna Richlin, Assistant Professor of Anthropology, University of MaineLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2244932024-03-01T13:33:21Z2024-03-01T13:33:21ZMeasles is one of the deadliest and most contagious infectious diseases – and one of the most easily preventable<figure><img src="https://images.theconversation.com/files/578746/original/file-20240228-16-96qj3k.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C2119%2C1414&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Young children, pregnant people and the immunocompromised are among the most vulnerable to measles.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/measles-royalty-free-image/534079149">CHBD/E+ via Getty Images</a></span></figcaption></figure><p>“You don’t count your children until the measles has passed.” <a href="https://www.nytimes.com/2022/11/05/health/samuel-katz-dead.html">Dr. Samuel Katz</a>, one of the pioneers of the first measles vaccine in the late 1950s to early 1960s, regularly heard this tragic statement from parents in countries where the measles vaccine was not yet available, because they were so accustomed to losing their children to measles.</p>
<p>I am a <a href="https://som.cuanschutz.edu/Profiles/Faculty/Profile/25677">pediatrician and preventive medicine physician</a>, and I have anxiously watched measles cases rise worldwide while <a href="https://www.cdc.gov/media/releases/2023/p1116-global-measles.html">vaccination rates have dropped</a> since the early days of the COVID-19 pandemic due to disruptions in vaccine access and the spread of vaccine misinformation.</p>
<p>In 2022 alone, there were <a href="http://dx.doi.org/10.15585/mmwr.mm7246a3">over 9 million measles cases and 136,000 deaths worldwide</a>, an 18% and 43% increase from the year before, respectively. The World Health Organization warned that <a href="https://www.reuters.com/business/healthcare-pharmaceuticals/more-than-half-world-faces-high-measles-risk-who-says-2024-02-20/">over half the world’s countries</a> are at high risk of measles outbreaks this year.</p>
<p>The U.S. is no exception. The country is on track to have one of the worst measles years since 2019, when Americans experienced the <a href="https://www.cdc.gov/measles/cases-outbreaks.html">largest measles outbreak</a> in 30 years. As of mid-February 2024, <a href="https://www.cdc.gov/measles/cases-outbreaks.html">at least 15 states</a> have reported measles cases and multiple ongoing, uncontained outbreaks.</p>
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<figcaption><span class="caption">Measles is on the rise across the U.S. once again, despite being eliminated in 2000.</span></figcaption>
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<p>While this measles crisis unfolds, U.S. measles vaccination rates are at the <a href="http://dx.doi.org/10.15585/mmwr.mm7245a2">lowest levels in 10 years</a>. Prominent figures like the <a href="https://www.washingtonpost.com/health/2024/02/22/florida-measles-outbreak-ladapo/">Florida surgeon general</a> are responding to local outbreaks in ways that run counter to science and public health recommendations. The spread of <a href="https://www.nbcnews.com/health/health-news/measles-outbreaks-anti-vaccine-misinformation-rcna136994">misinformation and disinformation</a> from anti-vaccine activists online further promotes misguided ideas that measles is not a serious health threat and measles vaccination is not essential. </p>
<p>However, the evidence is clear: Measles is <a href="https://www.cdc.gov/measles/symptoms/complications.html">extremely dangerous</a> for everyone, and especially for young children, pregnant people and people with compromised immune systems. But simple and effective tools are available to prevent it.</p>
<h2>Measles is a serious illness</h2>
<p>Measles is one of the most deadly infectious diseases in human history. Before a vaccine became available in 1963, around 30 million people were infected with measles and <a href="https://doi.org/10.1016/j.eclinm.2024.102502">2.6 million people died from the disease</a> every year worldwide. In the U.S., measles was responsible for an estimated 3 million to 4 million infections. Among reported cases, there were 48,000 hospitalizations, 1,000 cases of encephalitis, or brain swelling, and 500 deaths <a href="https://www.cdc.gov/measles/about/history.html">every year</a>. </p>
<p>Measles is also one of the most contagious infectious diseases. According to the Centers for Disease Control and Prevention, <a href="https://www.cdc.gov/measles/about/parents-top4.html">up to 9 out of 10 people</a> exposed to an infected person will become infected if they don’t have protection from vaccines. The measles virus can stay in the air and infect others for up to two hours after a contagious person has left the room. Measles can also hide in an unknowing victim for <a href="https://www.cdc.gov/vaccines/pubs/surv-manual/chpt07-measles.html">one to two weeks and sometimes up to 21 days</a> before symptoms begin. Infected people can <a href="https://www.cdc.gov/measles/transmission.html">spread measles</a> for up to four days before they develop its characteristic rash, and up to four days after. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/578749/original/file-20240228-20-nsp7wf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Close-up of abdomen with red measles rash" src="https://images.theconversation.com/files/578749/original/file-20240228-20-nsp7wf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/578749/original/file-20240228-20-nsp7wf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/578749/original/file-20240228-20-nsp7wf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/578749/original/file-20240228-20-nsp7wf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/578749/original/file-20240228-20-nsp7wf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/578749/original/file-20240228-20-nsp7wf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/578749/original/file-20240228-20-nsp7wf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">One characteristic measles symptom is a rash that spreads from the face to the rest of the body.</span>
<span class="attribution"><a class="source" href="https://phil.cdc.gov/details.aspx?pid=3168">CDC/Heinz F. Eichenwald, MD</a></span>
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<p>The <a href="https://www.cdc.gov/measles/symptoms/signs-symptoms.html">initial symptoms</a> of measles are similar to those of many other common viral illnesses in the U.S.: fever, cough, runny nose and red eyes. Several days after symptoms begin, characteristic tiny white spots develop inside the mouth, and a facial rash spreads to the rest of the body. </p>
<p>While most people’s symptoms improve, 1 in 5 unvaccinated children will be hospitalized, 1 out of every 1,000 will develop brain swelling that can lead to brain damage, and up to <a href="https://www.cdc.gov/measles/symptoms/complications.html#">3 of every 1,000 will die</a>. For unvaccinated people who are pregnant, measles infection can lead to miscarriage, stillbirth, premature birth and low birth weight.</p>
<p>The risk of severe complications from measles persists even after a person appears to be fully recovered. In rare cases, people can experience a brain disease called <a href="https://www.ninds.nih.gov/health-information/disorders/subacute-sclerosing-panencephalitis#">subacute sclerosing panencephalitis</a> that develops seven to 10 years after infection and leads to memory loss, involuntary movements, seizures, blindness and eventually death.</p>
<p>Beyond these individual health effects, the <a href="https://www.idsociety.org/science-speaks-blog/2022/estimating-the-impact-how-much-does-a-measles-outbreak-cost/#/+/0/publishedDate_na_dt/desc/">financial cost</a> to society for containing measles outbreaks is significant. For example, a 2019 measles outbreak in Washington state is estimated to have cost <a href="https://doi.org/10.1542/peds.2020-027037">US$3.4 million</a>. Necessary efforts to control measles outbreaks pull millions of dollars’ worth of critical resources away from other essential public health functions such as ensuring food safety, preventing injuries and chronic diseases, and responding to disasters.</p>
<h2>Vaccines protect against measles</h2>
<p>Why put communities at risk and allow these societal costs from measles when effective and safe tools are available to protect everyone?</p>
<p>Measles vaccines have been so effective, providing lifelong protection to <a href="https://www.cdc.gov/measles/vaccination.html">over 97% of people</a> who receive two vaccine doses, that they are victims of their own success. Initial widespread measles vaccination had reduced measles cases by 99% compared to before the vaccine was available, and consequently, most people in the U.S. are unaware of the seriousness of this disease.</p>
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<a href="https://images.theconversation.com/files/578753/original/file-20240228-7861-io367m.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Person looking at Florida Health measles and MMR shot information sheet" src="https://images.theconversation.com/files/578753/original/file-20240228-7861-io367m.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/578753/original/file-20240228-7861-io367m.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=454&fit=crop&dpr=1 600w, https://images.theconversation.com/files/578753/original/file-20240228-7861-io367m.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=454&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/578753/original/file-20240228-7861-io367m.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=454&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/578753/original/file-20240228-7861-io367m.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=570&fit=crop&dpr=1 754w, https://images.theconversation.com/files/578753/original/file-20240228-7861-io367m.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=570&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/578753/original/file-20240228-7861-io367m.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=570&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Measles is a highly preventable disease.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/measles-information-sheet-is-seen-posted-at-the-orange-news-photo/1141724959">Paul Hennessy/NurPhoto via Getty Images</a></span>
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<p>Despite the success of highly effective vaccination programs in the U.S., anyone can still come into contact with measles in their community. Measles is most often brought into the U.S. by <a href="https://www.cdc.gov/measles/about/parents-top4.html">unvaccinated American travelers</a> returning home and sometimes from foreign visitors. For people traveling out of the country, the threat of measles exposure is even greater, with widespread outbreaks occurring in <a href="https://wwwnc.cdc.gov/travel/notices/level1/measles-globe">many travel destinations</a>.</p>
<p>Public health leaders who embrace and promote vaccination and follow simple, proven infectious disease containment measures can help prevent measles disease spread. Every single preventable illness, complication, hospitalization or death from measles is one too many.</p><img src="https://counter.theconversation.com/content/224493/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>David Higgins is affiliated with Immunize Colorado, a nonprofit that works to protect Colorado families, schools and communities from vaccine-preventable diseases (volunteer non-paid board of directors member) and American Academy of Pediatrics (volunteer non-paid chapter immunization representative for the Colorado chapter).</span></em></p>A pediatrician and preventive medicine physician explains how measles vaccines became victims of their own success and the risk that rising outbreaks pose to everyone.David Higgins, Research Fellow and Instructor in Pediatrics, University of Colorado Anschutz Medical CampusLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2229892024-02-27T18:00:31Z2024-02-27T18:00:31ZUnintended consequences of NZ’s COVID vaccine mandates must inform future pandemic policy – new research<p>During the height of the COVID-19 pandemic, policy was being made in crisis management mode. Decisions had to be made faster than usual, and there was limited ability to undertake wider consultation and impact analysis.</p>
<p>Now the worst of the pandemic is over, we have the luxury of being able to reflect on what worked well and what didn’t. </p>
<p>One of the more controversial policies implemented during the height of the pandemic was the <a href="https://theconversation.com/vaccine-mandates-for-nzs-health-and-education-workers-are-now-in-force-but-has-the-law-got-the-balance-right-171392">vaccine mandates</a>. Thousands of workers across a range of professions had to get vaccinated to keep their jobs. </p>
<p>This mandate presented a trade-off between public health considerations and the right of individuals to refuse medical treatment and earn a living in their chosen profession.</p>
<p>Our <a href="https://workresearch.aut.ac.nz/__data/assets/pdf_file/0006/867876/Vaccine-Mandates-Final-Version.pdf">research</a> looked at whether these vaccine mandates increased COVID-19 vaccination rates among these workers, and what their employment, earnings and workplace experiences were. </p>
<p>The stated purpose of the mandates was to increase vaccination rates among these workers to <a href="https://www.simpsongrierson.com/insights-news/legal-updates/the-end-of-vaccine-mandates">ensure the continuity</a> of public services. </p>
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<a href="https://theconversation.com/covid-vaccines-dont-violate-the-nuremberg-code-heres-how-to-convince-the-doubters-171217">COVID vaccines don't violate the Nuremberg Code. Here's how to convince the doubters</a>
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<p>In reality, the mandates had limited effect on increasing vaccine uptake. But they had a substantive negative effect on the employment, earnings and wellbeing of unvaccinated health workers.</p>
<h2>The importance of choice</h2>
<p>Vaccination rates among healthcare, education and corrections workers were already high when the government announced the mandates in October 2021.</p>
<p>Almost 90% of healthcare workers and 86% of corrections workers had already received two doses of the vaccine. The share among education workers was somewhat lower (82%), but they also did not have early access to the vaccine. There were only six weeks between the vaccine becoming available to everyone over 12 years and the mandates being announced. </p>
<p>While vaccination rates among these mandated workers did increase after the mandates were announced, the data shows a continuation of an upward trend rather than a jump in uptake. </p>
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<p>It won’t surprise anyone that people don’t like being told what to do. And this appears to have some bearing on mandatory vaccine uptake. </p>
<p>One <a href="https://www.pnas.org/doi/full/10.1073/pnas.2118721119#:%7E:text=While%20fluid%2C%20opposition%20to%20vaccination,opposed%20if%20vaccination%20were%20mandated.">German survey</a> found just over 3% of people said they would not want the COVID-19 vaccination if it was voluntary. But more than 16% said they would not want to get vaccinated if it was mandatory. </p>
<p>A consequence of vaccine mandates is that they can erode trust in government and provoke more resistance. This erosion of trust could potentially <a href="https://www.annualreviews.org/doi/10.1146/annurev-publhealth-090419-102240">strengthen anti-vaccination sentiment</a> generally and reduce uptake, not just of COVID-19 vaccinations, but also other vaccines. </p>
<p>This outcome is especially concerning given research has found New Zealand’s <a href="https://workresearch.aut.ac.nz/__data/assets/pdf_file/0011/851555/Assessing-the-impact-of-the-COVID-19-pandemic-on-childhood-vaccine-uptake-with-integrated-administrative-data_revised-20240111.pdf;%20https://www.tandfonline.com/doi/full/10.1080/21645515.2023.2301626">routine childhood immunisation rates have decreased</a> since the pandemic. </p>
<h2>Earnings took a hit</h2>
<p>In addition to not causing a noticeable increase in vaccination rates, the mandates also had negative consequences for the employment and earnings of unvaccinated health workers. </p>
<p>Their employment rate fell by 15% and their earnings fell by 19%, compared with vaccinated health workers and those not subject to the mandates.</p>
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Read more:
<a href="https://theconversation.com/parents-were-fine-with-sweeping-school-vaccination-mandates-five-decades-ago-but-covid-19-may-be-a-different-story-168899">Parents were fine with sweeping school vaccination mandates five decades ago – but COVID-19 may be a different story</a>
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<p>Even after the health worker mandates were lifted in September 2022, the employment and earnings of unvaccinated workers never fully recovered. </p>
<p>This exacerbated existing health worker shortages. Closed borders and a global shortage of healthcare workers meant fewer moved into the health sector compared with the number leaving. </p>
<h2>The trauma of being branded ‘anti-vax’</h2>
<p>The effect of the mandates on health workers also went beyond financial consequences. </p>
<p>Affected health workers talked to us about the loss and ongoing trauma they have experienced. Those opposed to mandates are often incorrectly labelled as “anti-vaxxers”, or even conspiracy theorists. </p>
<p>All health workers we spoke to were pro-vaccination, but had legitimate reasons for not completing, or struggling to complete, the required vaccinations. They had researched the vaccine and made informed decisions based on their circumstances. </p>
<p>Some health workers pointed out that the case for mandates was not strong based on available evidence. While the vaccine reduces symptom severity, its ability to prevent transmission is <a href="https://onlinelibrary-wiley-com.ezproxy.aut.ac.nz/doi/pdfdirect/10.1111/bioe.13141">currently limited</a>. </p>
<p>As one health worker said: </p>
<blockquote>
<p>I looked at the Australian data and couldn’t see the logic of me potentially being exposed to another vaccine where my potential benefit was so low […] the evidence wasn’t really strong.</p>
</blockquote>
<p>Some workers had health conditions that put them at elevated risk from the vaccine. Or they had a history of adverse reactions to vaccines. But the mandates meant they either had to get vaccinated, sometimes against their doctors’ advice, or lose their jobs. While some medical exemptions were available, the threshold for these was very high.</p>
<p>In addition, even those with medical exemptions faced stigma. One health worker who got an exemption after suffering a stroke following their vaccination, described people’s reaction upon showing them the exemption.</p>
<blockquote>
<p>That look on people’s faces, it was disgust […] it was really, really awful. </p>
</blockquote>
<p>As another health worker explained:</p>
<blockquote>
<p>We’re supposed to be a caring profession. Nothing about this is caring […] Due to no fault of my own, I have now been labelled an anti-vaxxer and anti-science, and in some people’s opinion, not worthy of calling myself a nurse. This hurts me immensely. This is what mandates have done. There is no room for individual circumstances.</p>
</blockquote>
<p>The people we spoke with said they lost their sense of control, and it eroded their trust in the health system and government. </p>
<h2>The risk of mandates</h2>
<p>What does this tell us about the use of vaccine mandates during future pandemics? </p>
<p>In the context of high voluntary compliance, mandates should be used judiciously. Mandating something is not always the most effective way to get people to do something for the greater good. </p>
<p>During the COVID-19 pandemic, a strong motivator for vaccination was the “feel-good” factor of knowing you were protecting yourself and others. </p>
<p>Ironically, the increase in distrust that resulted from the use of mandates in the COVID-19 pandemic may actually lower voluntary vaccine uptake in future pandemics.</p>
<p>As one health worker summed it up:</p>
<blockquote>
<p>Someone who’s been vaccinated badly, the trauma of that – it’s not just them, it’s their entire social circle, it’s their entire whānau. You’re seeding distrust in the health system, not just for COVID vaccinations, but the whole system, everything to do with medicine and the whole immunisation programme […] if there’s a policy that’s as big as a mandate for a whole population or health professionals, you really need to think about what are the unintended consequences.</p>
</blockquote><img src="https://counter.theconversation.com/content/222989/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>This research received funding from the Ministry of Health.</span></em></p><p class="fine-print"><em><span>Denise Wilson, Gail Pacheco, and Lisa Meehan do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Mandates were meant to ensure continuity of public services during the pandemic. But a new study suggests they had limited impact on vaccination rates, while significantly hurting careers and eroding trust.Jan Dewar, Head of Nursing, Auckland University of TechnologyDenise Wilson, Associate Dean Māori Advancement | Professor Māori Health, Auckland University of TechnologyGail Pacheco, Professor of Economics, Director of the NZ Work Research Institute, Auckland University of TechnologyLisa Meehan, Deputy Director, NZ Work Research Institute, Auckland University of TechnologyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2224372024-02-01T18:09:43Z2024-02-01T18:09:43ZWhy Taylor Swift is an antihero to the GOP − but Democrats should know all too well that her endorsement won’t mean it’s all over now<figure><img src="https://images.theconversation.com/files/572838/original/file-20240201-29-3iozq0.jpeg?ixlib=rb-1.1.0&rect=17%2C0%2C5973%2C3979&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Travis Kelce celebrates with Taylor Swift on Jan. 28, 2024, after the Kansas City Chiefs defeated the Baltimore Ravens in the AFC championship game.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/travis-kelce-of-the-kansas-city-chiefs-celebrates-with-news-photo/1970250651?adppopup=true">Patrick Smith/Getty Images</a></span></figcaption></figure><p>A pop <a href="https://people.com/travis-kelce-reveals-when-he-taylor-swift-romance-first-began-8557241">icon falling for one of the NFL’s preeminent superstars</a> may seem like a slice of Americana – a scene from a small-town high school magnified by a factor of 10 million. </p>
<p>But this is America in 2024 so, of course, nothing magical stays that way. </p>
<p>To be clear, public opinion data suggests that most Americans think Taylor Swift is <a href="https://maristpoll.marist.edu/polls/taylor-swift-the-nfl/">good for the NFL</a>. But with her beau Travis Kelce’s Kansas City Chiefs heading to a fourth Super Bowl in five years, and with Swift herself reportedly preparing for a journey <a href="https://www.nbcbayarea.com/news/sports/nfl/taylor-swift-super-bowl-chiefs-tokyo-japan-concert-report/3435863/">across the globe</a> to cheer him on in the big game, the right-wing talk machine has gone into overdrive.</p>
<p>Fox News host <a href="https://www.politico.com/news/2024/01/10/pentagon-taylor-swift-fox-00134866">Jesse Watters suggested</a> that Swift may be a Pentagon asset used to combat online misinformation. Former GOP presidential candidate <a href="https://www.nydailynews.com/2024/01/29/vivek-ramaswamy-says-super-bowl-could-be-rigged-to-boost-taylor-swift-and-biden/">Vivek Ramaswamy tweeted</a> that he thinks Swift and Kelce are being artificially propped up by the media pending an upcoming Swift endorsement of Joe Biden. OAN referred to the couple as a “<a href="https://www.mediaite.com/media/oan-host-rails-against-americas-love-for-football-in-tirade-over-travis-kelce-and-taylor-swift-psy-op/">Massive Super Bowl Psy-op</a>,” a brainwashing campaign designed to indoctrinate citizens to an elite agenda and away from religion.</p>
<p>The idea that the Swift-Kelce romance is some sort of deep-state plot is perhaps gaining some traction in far-right circles because it lines up with other right-wing conspiracy theories and the right’s broader agenda. </p>
<h2>Swift’s NFL fandom</h2>
<p>Swift has <a href="https://theconversation.com/taylor-swift-person-of-the-year-and-political-influencer-208631">endorsed Democrats</a> in the past, including Joe Biden in 2020. Kelce, while not politically outspoken, was featured in a <a href="https://www.usatoday.com/story/news/health/2023/10/02/travis-kelce-promotes-flu-covid-19-shots-pfizer/71033013007/">Pfizer ad</a> touting the COVID-19 vaccine. </p>
<p>Republicans are more likely than Democrats to believe, without evidence, that <a href="https://www.theatlantic.com/ideas/archive/2023/01/conspiratorial-thinking-polarization-america-united-kingdom/672726/">a secret group of rulers is controlling the world</a>, as well as <a href="https://www.politico.com/news/2023/09/23/gop-voters-vaccines-poll-00117125">that vaccines cause autism</a>. While there isn’t public opinion data yet on the theories from Fox News and the right-wing echo chamber that the Swift-Kelce romance is an elaborate left-wing scheme, it contains elements of similar conspiracies for which partisan splits exist.</p>
<p>And opinions on Swift herself are similarly polarized. The singer is viewed favorably among virtually all groups in America, <a href="https://www.nbcnews.com/politics/taylor-swift-transcends-americas-political-divides-barely-rcna125908">although Republicans</a> are the only group in which as many members dislike Swift as like her.</p>
<p>Taylor Swift has brought a unique element to NFL fandom. I haven’t seen fans of my hometown Buffalo Bills <a href="https://twitter.com/LavenderKelce/status/1749147389728784475">make signs</a> denigrating a pop star since they thought Jon Bon Jovi wanted to buy the team and <a href="https://www.cbsnews.com/newyork/news/bills-to-toronto-concerns-raised-by-documents-is-buffalo-being-played/">move it to Toronto</a> in 2014.</p>
<p>Yet, <a href="https://library.park.edu/scholarsatwork/matthewharris">as a political scientist</a>, I know it’s an open question whether any of this matters politically.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/572840/original/file-20240201-25-7rtsex.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A man in a blue blazer, white shirt and rep tie gestures with open hands." src="https://images.theconversation.com/files/572840/original/file-20240201-25-7rtsex.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/572840/original/file-20240201-25-7rtsex.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/572840/original/file-20240201-25-7rtsex.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/572840/original/file-20240201-25-7rtsex.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/572840/original/file-20240201-25-7rtsex.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/572840/original/file-20240201-25-7rtsex.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/572840/original/file-20240201-25-7rtsex.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Fox News host Jesse Watters has speculated, without evidence, that Swift may be a Pentagon asset.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/host-jesse-watters-as-jesse-watters-primetime-debuts-on-fox-news-photo/1552264944?adppopup=true">Roy Rochlin/Getty Images</a></span>
</figcaption>
</figure>
<h2>Oprah, Obama and celebrity endorsements</h2>
<p>In the background of these conspiracy theories is the possibility that Taylor Swift could <a href="https://www.nytimes.com/2024/01/29/us/politics/biden-trump-election-taylor-swift.html">endorse Joe Biden</a>. The Trump campaign is reportedly thinking about such a possibility, with allies talking behind the scenes about a <a href="https://www.rollingstone.com/politics/politics-features/donald-trump-more-popular-taylor-swift-maga-biden-1234956829/">“holy war”</a> against Swift, brainstorming ways of painting her as a left-wing celebrity advancing an elite Democratic agenda.</p>
<p>But how much would such an endorsement matter? </p>
<p>In political science literature, a hallmark case of the power of celebrity endorsements is <a href="https://doi.org/10.1093/jleo/ewr031">Oprah Winfrey’s 2008 backing of Barack Obama</a>. Winfrey’s endorsement occurred during a primary in which he was taking on a more well-known opponent, Hillary Clinton. </p>
<p>Winfrey’s endorsement, wrote the authors of a prominent study of the case, led participants in the study “to see Obama as more likely to win the nomination and to say that they would be more likely to vote for him.” In other words, it helped advance public perceptions of Obama’s <a href="https://doi.org/10.1177/1940161208321948">viability as a candidate</a>.</p>
<p>A Swift endorsement of Biden would be different. </p>
<p>Swifties are <a href="https://theconversation.com/taylor-swift-person-of-the-year-and-political-influencer-208631">largely suburban and young</a>. Almost <a href="https://pro.morningconsult.com/instant-intel/taylor-swift-fandom-demographic">half are millennials</a>, and over 10% belong to Gen Z. They represent a slice of the youth vote that candidates have attempted to court for decades, and the <a href="https://www.politico.com/f/?id=0000017f-bcf4-d17b-a1ff-bef5e8a70000">suburbs are increasingly a battleground</a> in the country’s urban-rural divide. A Swift Instagram post in 2023 helped lead to <a href="https://www.npr.org/2023/09/22/1201183160/taylor-swift-instagram-voter-registration">35,000 new voter registrations</a> – and her ability to generate funds could also be <a href="https://www.nytimes.com/2024/01/29/us/politics/biden-trump-election-taylor-swift.html">invaluable to Biden</a>. </p>
<p>But an Oprah-like effect is less likely for a Swift endorsement of Biden, who is running as an incumbent without a serious primary challenger and his status as the Democratic nominee is certain.</p>
<p>Further, polling demonstrates that the effect of a Swift endorsement could be essentially <a href="https://abc3340.com/news/nation-world/18-of-voters-more-likely-to-back-taylor-swift-endorsed-presidential-candidate-poll-shows-2024-election-voting-ballot-biden-trump-white-house-politics-travis-kelce-kansas-city-chiefs">a net wash</a>, with 18% of the public saying they’d be more likely to support a Swift-backed candidate and 17% saying they would be less likely to support Swift’s favored choice. </p>
<p>Even those numbers might be affected by <a href="https://doi.org/10.1007/s11109-013-9238-0">partisan-motivated reasoning</a>, where a person’s party identification colors their perceptions of information. Swift’s prior backing of Democrats and perceived liberalism might cause her supporters and detractors to use polling questions asking about a potential Swift endorsement to express support or disfavor of her, regardless of how her endorsement would actually influence their choice. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/572842/original/file-20240201-23-hzjgww.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A man in a blue blazer, blue tie and white shirt in front of an American flag, holding his right hand in a fist." src="https://images.theconversation.com/files/572842/original/file-20240201-23-hzjgww.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/572842/original/file-20240201-23-hzjgww.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/572842/original/file-20240201-23-hzjgww.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/572842/original/file-20240201-23-hzjgww.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/572842/original/file-20240201-23-hzjgww.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/572842/original/file-20240201-23-hzjgww.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/572842/original/file-20240201-23-hzjgww.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A Swift endorsement, if it comes, could be less important than Donald Trump’s response to that endorsement.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/republican-presidential-candidate-and-former-u-s-president-news-photo/1965960388?adppopup=true">David Becker/Getty Images</a></span>
</figcaption>
</figure>
<h2>Not just a love story</h2>
<p>Essentially, a Swift endorsement might matter at the margins, but there are many, many other factors at play in a general election. That’s especially true in an election between two men who have both served as commander in chief, a <a href="https://www.pewresearch.org/short-reads/2022/11/16/few-former-presidents-have-run-for-their-old-jobs-or-anything-else-after-leaving-office/">rarity in American politics</a>.</p>
<p>A Swift endorsement, then, is perhaps less important in and of itself than Donald Trump’s response to a Swift endorsement of Biden. </p>
<p>Public opinion polling in the wake of Trump’s Access Hollywood remarks in 2016 showed that majorities of both women and men believed Trump had little or no <a href="https://www.pewresearch.org/short-reads/2016/11/04/trump-respect-for-women/">respect for women</a>. But Trump actually improved his numbers among <a href="https://www.pewresearch.org/politics/2021/06/30/behind-bidens-2020-victory/">women voters in 2020</a>. </p>
<p>A Swift endorsement of Biden could bring out some of Trump’s worst impulses. Perhaps the effect of his response on how voters view him could be more important than her endorsement of Biden.</p><img src="https://counter.theconversation.com/content/222437/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Matt Harris does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>The idea that the Swift-Kelce romance is some sort of deep-state plot is perhaps gaining traction in far-right circles because it lines up with the political right’s broader agenda and beliefs.Matt Harris, Associate Professor of Political Science, Park UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2212912024-01-19T07:24:56Z2024-01-19T07:24:56ZMeasles is the most infectious disease known to science – adults should consider getting another MMR vaccine<figure><img src="https://images.theconversation.com/files/569842/original/file-20240117-23-b5my4a.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C2053%2C2996&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Adult MMR jabs could play an important role in preventing measles outbreaks</span> <span class="attribution"><a class="source" href="https://www.gettyimages.co.uk/detail/news-photo/syringes-containing-the-mumps-measles-and-rubella-vaccine-news-photo/57470629?adppopup=true">Mark Kegans/Getty Images</a></span></figcaption></figure><p>Imagine a disease more infectious than any other known to medical science, that would kill <a href="https://www.who.int/news-room/fact-sheets/detail/measles">2.6 million young children every year</a> and leave millions more with deafness and even brain damage. It sounds like something from pandemic horror fiction, but such a disease does exist – measles. </p>
<p>Yet even measles was tamed across the world, at least for a while. In the aftermath of the successful eradication of smallpox in the 1970s, a similar global vaccination effort crushed measles mortality from 2.6 million in 1980 down to <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5388903/">73,000 by 2014</a>.</p>
<p>Measles’ R number (the average number of people someone with the virus will go on to infect) of 15 or more puts even the most rampant variants of SARS-CoV-2 in the shade. Because of this infectiousness, it’s never been quite possible to achieve eradication, but many countries have been declared <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5069432/">measles-free</a> by the World Health Organization.</p>
<p>This achievement isn’t necessarily permanent, however. The UK was deemed measles-free in 2016 but lost its status just two years later. And now there are rising case numbers across England, with <a href="https://www.bbc.co.uk/news/uk-england-birmingham-68007804">significant outbreaks</a> in London and the west Midlands.</p>
<p>The principal weapon in the war against measles has been the MMR vaccine, rolled out from 1971, which also provides immunity against <a href="https://www.nhs.uk/conditions/mumps/">mumps</a> and <a href="https://www.who.int/news-room/fact-sheets/detail/rubella">rubella</a> – two other viruses with potentially nasty long-term effects. </p>
<p>MMR’s global deployment was perhaps the greatest public health triumph of the last quarter of the 20th century, saving at least 56 million lives <a href="https://www.who.int/news-room/fact-sheets/detail/measles">by WHO estimates</a>. </p>
<p>Until, in 1998, a spanner was thrown in the works when spurious claims were made in The Lancet about a connection between the MMR vaccine and autism. In 2010, <a href="https://www.bmj.com/content/340/bmj.c696">the paper was retracted</a> by the journal and <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3136032/">its lead author, Andrew Wakefield, struck off</a> from practising medicine in the UK. But by then, the damage had been done. </p>
<p>Despite <a href="https://www.cdc.gov/vaccinesafety/vaccines/mmr/mmr-studies.html">numerous studies</a> confirming both the efficacy and safety of MMR, and failing to find any connection whatsoever with autism, many people began to have second thoughts about bringing their children in for vaccination. Vaccine hesitancy had set in, and measles began its insidious return, with global deaths climbing to <a href="https://www.bmj.com/content/383/bmj.p2733">136,000 in 2022</a>.</p>
<h2>Vaccine hesitancy and misinformation</h2>
<p>Vaccine hesitancy, <a href="https://theconversation.com/victorian-britain-had-its-own-anti-vaxxers-and-they-helped-bring-down-a-government-218671">although nothing new</a>, has become such a problem for public health services that it is the subject of intense research interest. </p>
<p>And it isn’t just scare stories about autism. <a href="https://pubmed.ncbi.nlm.nih.gov/33684019/">Studies have revealed</a> the full complexity of the problem – that there is no single factor which vaccine-hesitant people share, and therefore no obvious, easy public educational strategy to solve the problem. </p>
<p>Those who are <a href="https://pubmed.ncbi.nlm.nih.gov/30476112/">less educated</a> have a tendency to hesitancy – but so do those who are <a href="https://pubmed.ncbi.nlm.nih.gov/28757057/">highly educationally qualified</a>. Likewise, those who <a href="https://bmcpublichealth.biomedcentral.com/articles/10.1186/s12889-018-5103-8">hold deep religious convictions</a> but also those who are <a href="https://pubmed.ncbi.nlm.nih.gov/31262584/">militantly anti-religious</a>, those who <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0191728">distrust the nanny state</a>, those who distrust capitalism and particularly <a href="https://pubmed.ncbi.nlm.nih.gov/31431420/">the pharmaceuticals industry</a>, <a href="https://pubmed.ncbi.nlm.nih.gov/30639802/">the poorest in society and the richest</a> – all these groups show elevated levels of vaccine hesitancy, yet often have little else in common at all. </p>
<p>In contrast, a middle-of-the-road, middle-income, reasonably educated person with weakly held religious beliefs is the most likely to be found in the queue at the vaccination station. We still do not really know why.</p>
<p>Vaccine hesitancy is now a problem for all vaccination programmes but particularly measles, since its R of 15 or more means that any drop in vaccine coverage will result in a rapid increase in cases. </p>
<p>Where vaccine coverage becomes locally low, there can be <a href="https://theconversation.com/over-3-000-killed-by-deadly-virus-in-democratic-republic-of-the-congo-this-year-and-its-not-ebola-123220">local epidemics of considerable severity</a>. Many countries have now <a href="https://www.bbc.co.uk/news/health-49507253">lost their hard-earned measles-free status</a>, in Europe including Albania, the Czech Republic and Greece, as well as the UK.</p>
<p>But there is one thing we can all do to help – and if you live in the UK, <a href="https://www.nhs.uk/conditions/vaccinations/nhs-vaccinations-and-when-to-have-them/">the NHS can help you do it</a>. </p>
<h2>MMR is not just for kids</h2>
<p>Even if an adult has received MMR as a child or survived an attack of measles in the pre-vaccination days, their <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8189124/">immunity can wane</a>. Although the risk of a second attack bad enough to produce the symptoms seen in unprotected children is very small, adult MMR is still worthwhile as it goes beyond just protecting the person who receives the vaccination.</p>
<p>By bolstering the immunity of adults against these three viruses, it decreases the likelihood of an <a href="https://pubmed.ncbi.nlm.nih.gov/10443793/">asymptomatic infection</a> and prevents an adult becoming an unwitting carrier. Adult MMR can help to restore some of the herd immunity that has been lost due to vaccine hesitancy.</p>
<figure class="align-center ">
<img alt="Two women and baby are in a medical office with yellow walls. One of the women holds a baby, who's dressed in pink and looks unhappy, while the other woman, dressed in a nurse's uniform administers a vaccine to the baby." src="https://images.theconversation.com/files/569840/original/file-20240117-23-52meji.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/569840/original/file-20240117-23-52meji.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=406&fit=crop&dpr=1 600w, https://images.theconversation.com/files/569840/original/file-20240117-23-52meji.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=406&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/569840/original/file-20240117-23-52meji.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=406&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/569840/original/file-20240117-23-52meji.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=510&fit=crop&dpr=1 754w, https://images.theconversation.com/files/569840/original/file-20240117-23-52meji.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=510&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/569840/original/file-20240117-23-52meji.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=510&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Measles vaccines aren’t only for children.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.co.uk/detail/news-photo/month-old-amelia-down-sits-on-the-lap-of-her-mother-helen-news-photo/167095249?adppopup=true">Geoff Caddick/AFP via Getty Images</a></span>
</figcaption>
</figure>
<p>Babies under a year of age cannot receive MMR, so they are the most vulnerable. Opting for adult MMR helps protect those babies from measles, and it helps prevent rubella in pregnant women and their babies. </p>
<p>And if you’re a man of a certain age, opting for adult MMR also protects you personally against orchitis – the dreaded <a href="https://www.nhs.uk/conditions/mumps/complications/">inflammation of the testicles</a> that is a symptom of mature men’s mumps.</p>
<p>It would be a tragedy for the world to return to the days of uncontrolled measles epidemics due to sustained vaccine hesitancy over MMR. Let’s get herd immunity against measles back up to where it should be by choosing adult MMR.</p><img src="https://counter.theconversation.com/content/221291/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Derek Gatherer receives funding from the UK Economic & Social Research Council for work on vaccine hesitancy.</span></em></p>Herd immunity to measles is waning due to vaccine hesitancy over MMR. Adult MMR is one way to help get it back up again.Derek Gatherer, Lecturer, Biomedical and Life Sciences, Lancaster UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2209802024-01-15T20:46:57Z2024-01-15T20:46:57ZRSV, flu and COVID: demystifying the triple epidemic of respiratory viruses<figure><img src="https://images.theconversation.com/files/568892/original/file-20240110-27-k3w5hm.jpg?ixlib=rb-1.1.0&rect=0%2C2%2C995%2C663&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The influenza virus, which causes seasonal flu, is back at its usual rate after a hiatus due to health measures.</span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><p>Since 2022, a triple epidemic of respiratory viruses — RSV, influenza and SARS-CoV-2 — has been disrupting our daily lives. In addition, the media constantly reminds us of how this is straining emergency departments.</p>
<p>How does the present respiratory virus season differ from seasons during the pre-COVID era?</p>
<p>As a specialist in virus-host interaction, I would like to shed some light on the new dynamics of the respiratory virus season.</p>
<h2>The infamous SARS-CoV-2</h2>
<p>SARS-CoV-2, the instigator of the COVID-19 pandemic, is still with us. Despite limited access to screening tests, analysis of the number of hospital admissions shows that the virus is still going strong.</p>
<p>Québec’s Institut National de Santé Publique counted more than 33,000 hospitalizations in Québec in 2023 affecting all age categories, <a href="https://www.inspq.qc.ca/en/node/29197">including 648 children under the age of nine</a>.</p>
<p>The virus is not seasonal. It has a strikingly efficient capacity to spread through aerosols, especially as we take refuge indoors to escape the cold. The virus currently circulating is actually a mixture of different viruses, known as variants, each of which has the potential to partially evade the immunity an individual has acquired through a previous infection or vaccination.</p>
<h2>Resurgence of seasonal flu</h2>
<p>After a hiatus due to health measures, the influenza virus, which causes seasonal flu, has returned with the same force. It is once again circulating <a href="https://www.cdc.gov/flu/about/viruses/types.htm">in different variants belonging to Types (strains) A and B</a>, although scientists believe that one Type B strain, the <a href="http://doi.org/10.2807/1560-7917.ES.2022.27.39.2200753">Yamagata lineage, has disappeared</a>.</p>
<p>A variant of H1N1 Type A, different from the viruses that caused the 1918 and 2009 pandemics, is now dominant in North America where it is causing an increase in hospital admissions, <a href="https://www.canada.ca/en/public-health/services/publications/diseases-conditions/fluwatch/2023-2024/week-49-december-3-december-9-2023.html">especially among the elderly and young children</a>.</p>
<p>However, we must remain vigilant, as the strain may change within the same season. What could this mean? The target population could change, <a href="https://www.canada.ca/en/public-health/services/publications/diseases-conditions/fluwatch/2018-2019/annual-report.html">as it did in the 2018-2019 season</a>.</p>
<h2>And what about RSV?</h2>
<p>The respiratory syncytial virus (RSV) also appears to be <a href="https://www.canada.ca/en/public-health/services/surveillance/respiratory-virus-detections-canada/2023-2024/week-50-ending-december-16-2023.html">resuming its pre-pandemic transmission levels</a>.</p>
<p>RSV causes bronchiolitis and pneumonia. <a href="https://cps.ca/en/documents/position/bronchiolitis">Bronchiolitis is characterized by the obstruction of the small airways, which can progress to wheezing or respiratory distress</a>.</p>
<p>Virtually all children are infected with RSV before the age of 2, and RSV infection is one of the main causes of hospitalization in young children.</p>
<p>Before the COVID-19 pandemic, there was an average of 2,523 hospitalizations per year in Canada, <a href="https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2810133">half of them in children under six months of age and more than a quarter requiring admission to intensive care</a>.</p>
<p>But RSV also severely affects the elderly and adults who are immunocompromised or have existing chronic conditions. RSV shows high levels of severe illness, hospital admissions and in hospital deaths in adults, <a href="https://doi.org/10.1093/infdis/jiad559">figures which are comparable to those for influenza</a>.</p>
<p>Admittedly, although these three viruses are attracting attention, other less publicized respiratory viruses are also circulating, <a href="https://www.canada.ca/en/public-health/services/surveillance/respiratory-virus-detections-canada/2023-2024/week-50-ending-december-16-2023.html">demonstrating a diverse viral environment</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/568438/original/file-20240109-27-z61q6c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="woman in hospital" src="https://images.theconversation.com/files/568438/original/file-20240109-27-z61q6c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/568438/original/file-20240109-27-z61q6c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/568438/original/file-20240109-27-z61q6c.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/568438/original/file-20240109-27-z61q6c.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/568438/original/file-20240109-27-z61q6c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/568438/original/file-20240109-27-z61q6c.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/568438/original/file-20240109-27-z61q6c.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The continued presence of SARS-CoV-2 means our hospitals can’t catch their breath.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<h2>SARS-CoV-2 has turned everything upside down</h2>
<p>The presence of SARS-CoV-2 marks the principal difference from the pre-pandemic era, since it is augmenting the burden on an already weakened health-care system. The challenge is amplified by the extremely high transmission capacity of SARS-CoV-2 compared with influenza and RSV, which makes seasonal management much more complex.</p>
<p>Until the SARS-CoV-2 pandemic, the respiratory virus season had a fairly predictable beginning and end that was determined by virus surveillance over the years. Our systems were already struggling to absorb this seasonal increase in patients. But today, the picture has become even more complex with the continuing presence of SARS-CoV-2. And our hospitals, with no time to catch their breath, are struggling to keep up.</p>
<h2>Beyond infection</h2>
<p>The second major difference that should not be overlooked is SARS-CoV-2’s ability to cause widespread health problems well beyond the respiratory system. In addition, it causes long-term consequences after infection, such as post-COVID syndrome (also known as long COVID), which affects millions of people.</p>
<p>The extent of the consequences of infection and reinfection on human health remains uncertain, as does the effectiveness of vaccines in limiting these effects. The SARS-CoV-2 pandemic – with its exceptional transmission levels – has produced a large number of patients available for research. Coupled with unprecedented funding, this has made it possible to undertake research that has never been possible before on a post-viral syndrome.</p>
<p>Of course, the number of people infected with RSV or influenza globally each year does not even come close to the number infected with SARS-CoV-2, even at this stage of the pandemic. However, there is considerable evidence that, in addition to the acute symptoms and mortality associated with influenza and RSV, <a href="https://doi.org/10.1038/s41591-022-01810-6">post-viral conditions also exist</a>, as they do with SARS-CoV-2.</p>
<h2>The importance of vaccines</h2>
<p>The final distinction from the pre-pandemic period is the arrival of RSV vaccines. In Canada, the Arexvy vaccine has been approved for people over 60, and the Abrysvo vaccine was also approved for pregnant women, providing immunity to children from birth. However, these two vaccines have not yet been officially recommended. We are still waiting for a vaccine to be made available for children. The trio of vaccines against COVID-19, influenza and RSV will certainly help to reduce the severe symptoms associated with respiratory virus infections in the coming seasons.</p>
<p>However, our primary objective must be to reduce the incidence of respiratory virus infections. Despite vaccination, we can expect the mortality and morbidity associated with these infections to increase as the population ages.</p>
<p>All three viruses share a common trait — they spread through the air. Their transmission could be reduced by implementing passive strategies aimed at reducing the concentration of aerosols in indoor air.</p><img src="https://counter.theconversation.com/content/220980/count.gif" alt="La Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Nathalie Grandvaux received research funding from the Canadian Institutes of Health Research (CIHR), the Natural Sciences and Engineering Research Council of Canada (NSERC), the Fonds de recherche du Québec - Santé (FRQS), the Canada Foundation for Innovation (CFI), the Fondation du centre hospitalier de l'Université de Montréal, and the Ministère de l'économie et de l'innovation du Québec.</span></em></p>The current triple epidemic of respiratory viruses is affecting all age groups, prompting comparisons with the pre-COVID-19 era.Nathalie Grandvaux, Professeure en biochimie des interactions hôte-virus, Université de MontréalLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2151992024-01-04T13:45:37Z2024-01-04T13:45:37ZDrugs of the future will be easier and faster to make, thanks to mRNA – after researchers work out a few remaining kinks<figure><img src="https://images.theconversation.com/files/567750/original/file-20240103-21-2oxdyb.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C2448%2C1224&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Two hurdles mRNA drugs face are a short half-life and impurities that trigger immune responses.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/on-white-background-royalty-free-image/1411871727">BlackJack3D/iStock via Getty Images Plus</a></span></figcaption></figure><p>Vaccines have been reliably and affordably protecting people from diseases worldwide <a href="https://theconversation.com/from-smallpox-to-polio-vaccine-rollouts-have-always-had-doubters-but-they-work-in-the-end-161803">for centuries</a>. Until the COVID-19 pandemic, however, vaccine development was still a long and idiosyncratic process. Traditionally, researchers had to tailor manufacturing processes and facilities for each vaccine candidate, and the scientific knowledge gained from one vaccine was often not directly transferable to another. </p>
<p>But the COVID-19 mRNA vaccines brought a new approach to vaccine development that has far-reaching implications for how researchers make drugs to treat many other diseases. </p>
<p><a href="https://scholar.google.com/citations?user=C49y7YQAAAAJ&hl=en">I am a biochemist</a>, and <a href="https://www.umassmed.edu/LiLab/">my lab</a> at UMass Chan Medical School focuses on developing better ways to use mRNA as a drug. Although there are <a href="https://theconversation.com/customizing-mrna-is-easy-and-thats-what-makes-it-the-next-frontier-for-personalized-medicine-a-molecular-biologist-explains-216127">many possibilities</a> for what researchers can use mRNA to treat, some important limitations remain. Better understanding how mRNA-based drugs interact with the immune system and how they are degraded in human cells can help lead to safe, durable and effective treatments for a wide range of diseases.</p>
<h2>Some basics of mRNA drugs</h2>
<p>Messenger RNA, or mRNA, is made of four building blocks denoted by the letters A, C, G and U. The sequence of letters in an mRNA molecule conveys genetic information that directs how a protein is made. </p>
<p>An mRNA drug comprises two essential components: mRNA molecules, which code for desired proteins, and the lipid molecules – such as phospholipids and cholesterol – that encapsulate them. These <a href="https://doi.org/10.1016/j.jconrel.2015.08.007">mRNA-lipid nanoparticles, or LNPs</a>, are tiny spheres <a href="https://doi.org/10.1016/j.ymthe.2017.03.013">about 100 nanometers in diameter</a> that protect mRNA from degradation and facilitate its delivery into target cells. </p>
<p>Once inside cells, mRNA molecules instruct the cell’s machinery to produce the target protein required for a desired therapeutic effect. For example, the mRNA in the Pfizer-BioNTech and Moderna <a href="https://theconversation.com/how-mrna-vaccines-from-pfizer-and-moderna-work-why-theyre-a-breakthrough-and-why-they-need-to-be-kept-so-cold-150238">COVID-19 vaccines</a> directs cells to produce a harmless version of the virus’ spike protein that trains the immune system to recognize and better prepare for potential infection. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/v-NEr3KCug8?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">The science behind COVID-19 mRNA vaccines has been decades in the making.</span></figcaption>
</figure>
<p>From a drug development perspective, mRNA drugs offer significant advantages over traditional drugs because they are <a href="https://theconversation.com/customizing-mrna-is-easy-and-thats-what-makes-it-the-next-frontier-for-personalized-medicine-a-molecular-biologist-explains-216127">easily programmable</a>. Hundreds of pounds of mRNA can be made from readily available DNA templates, such that producing a different mRNA drug is as simple as changing the corresponding DNA templates. </p>
<p>More importantly, different mRNA drugs produced by the same set of methods will have similar properties. They will be delivered to the same tissues, trigger similar levels of immune responses and degrade in similar ways. This predictability significantly reduces the development risks and financial costs of developing mRNA drugs.</p>
<p>In addition to being easy to program, mRNA drugs have several other unique properties. For example, just like the mRNAs your body naturally produces, therapeutic mRNAs have a short half-life in cells: <a href="https://doi.org/10.1016%2Fj.jconrel.2015.08.007">about one day</a>. As a result, current mRNA technology is ideal for treatments that aren’t meant to last long in the body. </p>
<p>This is why vaccines are popular candidates for mRNA technology: They provide long-term protection against disease after brief exposure to the drug with few side effects. There are currently <a href="https://www.mdpi.com/1422-0067/24/3/2700">more than 30 mRNA vaccine candidates</a>, not including vaccines for COVID-19, in clinical trials.</p>
<h2>Self vs. nonself</h2>
<p>Another critical feature of mRNA drugs is their intrinsic ability to stimulate the immune system. This may sound paradoxical – after all, your cells already contain large amounts of mRNAs. Why would other mRNAs activate your immune system? How does your immune system distinguish between self and nonself mRNAs?</p>
<p>The first reason involves location. Therapeutic mRNAs enter cells using endosomes – sacs made of the cell’s membrane that take in materials from the cell’s environment. Your immune system can detect mRNA in endosomes because this is usually a sign of an RNA virus infection – cellular mRNAs normally don’t enter endosomes. When your immune system labels therapeutic mRNAs as viral material, it triggers <a href="https://doi.org/10.1016/j.immuni.2005.06.008">a strong inflammatory response</a> that can lead to severe side effects. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/567748/original/file-20240103-25-lqiluh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Diagram showing molecules entering a depression in the cell membrane which closes off to form a sac" src="https://images.theconversation.com/files/567748/original/file-20240103-25-lqiluh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/567748/original/file-20240103-25-lqiluh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/567748/original/file-20240103-25-lqiluh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/567748/original/file-20240103-25-lqiluh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/567748/original/file-20240103-25-lqiluh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/567748/original/file-20240103-25-lqiluh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/567748/original/file-20240103-25-lqiluh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Endocytosis is the process by which material outside the cell, such as mRNA molecules, is engulfed within the cell.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/illustration/endocytosis-process-cells-absorb-external-royalty-free-illustration/1621615509">alfa md/iStock via Getty Images Plus</a></span>
</figcaption>
</figure>
<p>One solution to this problem is to modify mRNA’s building blocks – specifically, changing the U, or uridine, to its chemical cousins, <a href="https://doi.org/10.1016/j.immuni.2005.06.008">pseudouridine</a> and <a href="https://doi.org/10.1016/j.jconrel.2015.08.051">N1-methylpseudouridine</a>. This subtle chemical change prevents the unwanted immune response while allowing the therapeutic mRNA to <a href="https://doi.org/10.1038%2Fmt.2008.200">direct the cell to make the protein it encodes</a>. The <a href="https://theconversation.com/tenacious-curiosity-in-the-lab-can-lead-to-a-nobel-prize-mrna-research-exemplifies-the-unpredictable-value-of-basic-scientific-research-214770">2023 Nobel Prize in physiology or medicine</a> was awarded to the scientists who made this breakthrough discovery. Both the Pfizer-BioNTech and Moderna <a href="https://doi.org/10.1021/acscentsci.1c00197">COVID-19 mRNA vaccines</a> use this technique.</p>
<p>The second source of unwanted immune response is impurities from mRNA production. To prepare mRNA from a DNA template, scientists use a protein called <a href="https://www.nature.com/scitable/definition/rna-polymerase-106/">RNA polymerase</a> that tends to make a small amount of side product called <a href="https://doi.org/10.1093/nar/gkr695">double-stranded RNA</a>. Unlike mRNA, which is single-stranded, double-stranded RNA has two chains that form a double helix. RNA viruses also form double-stranded RNA when they replicate, and exposing cells to double-stranded RNA can lead to a strong immune response.</p>
<p>Removing double-stranded RNA is challenging, especially at the industrial scale. Fortuitously, for mRNA vaccines, the residual amount of double-stranded RNA can stimulate the immune system to <a href="https://doi.org/10.1038/s41590-022-01163-9">enhance antibody responses</a>. However, for applications other than vaccines, a cleaner RNA product is necessary to reduce side effects.</p>
<h2>Moving beyond vaccines</h2>
<p>Although mRNA has the potential to transform drug development for various medical purposes, careful consideration is required to identify targets that align with the technology’s strengths.</p>
<p>For example, because there is currently a limit to how long mRNA can last in the body, treatments that need a protein to be present for only a short period of time to achieve a lasting therapeutic effect are ideal. One promising example in development is using mRNA that encodes CRISPR-Cas9 gene-editing proteins to knock out genes that cause specific diseases.</p>
<p>Researchers are exploring this strategy to develop a single-dose treatment for <a href="https://doi.org/10.1056/NEJMoa2107454">hereditary transthyretin amyloidosis</a>, a rare genetic disease caused by the accumulation of misfolded proteins in the heart and nerves. This disease is an ideal target for mRNA-based CRISPR gene therapy because the target protein is produced by the liver. Because most drugs pass through the liver, this makes it easier to deliver CRISPR-Cas9 mRNA to its target. In the next few years, a new generation of more precise <a href="https://doi.org/10.1038/d41586-023-03797-7">mRNA-based genome editing therapies</a> will enter clinical trials.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/567751/original/file-20240103-17-vch2ou.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Microscopy image of SARS-CoV-2 virus particles lining the a few vesicles in a cell" src="https://images.theconversation.com/files/567751/original/file-20240103-17-vch2ou.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/567751/original/file-20240103-17-vch2ou.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=449&fit=crop&dpr=1 600w, https://images.theconversation.com/files/567751/original/file-20240103-17-vch2ou.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=449&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/567751/original/file-20240103-17-vch2ou.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=449&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/567751/original/file-20240103-17-vch2ou.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=564&fit=crop&dpr=1 754w, https://images.theconversation.com/files/567751/original/file-20240103-17-vch2ou.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=564&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/567751/original/file-20240103-17-vch2ou.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=564&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Because the virus that causes COVID-19 (gold) and other RNA viruses enter cells through endosomes, mRNA drug impurities can elicit similar immune responses.</span>
<span class="attribution"><a class="source" href="https://flic.kr/p/2mrqrnx">NIAID/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>For treatments that need a specific protein to be present in the body for long periods of time or need to prompt little to no immune reaction, further advancements in mRNA technology are necessary to extend mRNA’s half-life and eliminate immune-triggering contaminants. Notable new developments in these areas include using <a href="https://doi.org/10.1101/2021.03.29.437587">computational algorithms</a> to optimize mRNA sequences in ways that enhance their stability and <a href="https://doi.org/10.1038/s41587-022-01525-6">engineering RNA polymerases</a> that introduce fewer side products that may cause an immune response. </p>
<p>Further advancements have the potential to enable a new generation of safe, durable and effective mRNA therapeutics for applications beyond vaccines.</p><img src="https://counter.theconversation.com/content/215199/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Li Li receives funding from NIH. </span></em></p>The COVID-19 pandemic demonstrated the promise of using mRNA as medicine. But before mRNA drugs can go beyond vaccines, researchers need to identify the right diseases to treat.Li Li, Assistant Professor of Biomedical Sciences, UMass Chan Medical SchoolLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2195792023-12-29T11:42:01Z2023-12-29T11:42:01ZWhy some people don’t trust science – and how to change their minds<figure><img src="https://images.theconversation.com/files/567234/original/file-20231222-23-r02y8p.png?ixlib=rb-1.1.0&rect=26%2C15%2C1421%2C1035&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Nasa/wikipedia</span></span></figcaption></figure><p>During the pandemic, a third of people in the UK reported that their trust in science had increased, <a href="https://doi.org/10.1371/journal.pone.0278169">we recently discovered</a>. But 7% said that it had decreased. Why is there such variety of responses?</p>
<p>For many years, it was thought that the main reason some people reject science was a simple deficit of knowledge and a mooted fear of the unknown. Consistent with this, <a href="https://doi.org/10.1177/0963662506070159">many surveys</a> reported that attitudes to science are more positive among those people who know more of the textbook science. </p>
<p>But if that were indeed the core problem, the remedy would be simple: inform people about the facts. This strategy, which dominated science communication through much of the later part of the 20th century, <a href="https://doi.org/10.1177/097172180901400202">has, however, failed</a> at multiple levels. </p>
<p>In <a href="https://link.springer.com/article/10.1023/A:1023695519981">controlled experiments</a>, giving people scientific information was found not to change attitudes. And in the UK, scientific messaging over genetically modified technologies <a href="https://doi.org/10.1177/097172180901400202">has even backfired</a>. </p>
<p>The failure of the information led strategy may be down to people discounting or avoiding information if it contradicts their beliefs – also known as <a href="https://doi.org/10.1037/1089-2680.2.2.175">confirmation bias</a>. However, a second problem is that some trust neither the message nor the messenger. This means that a distrust in science isn’t necessarily just down to a deficit of knowledge, but a <a href="https://doi.org/10.1177/097172180901400202">deficit of trust</a>. </p>
<p>With this in mind, many research teams including ours decided to find out why some people do and some people don’t trust science. <a href="https://doi.org/10.1371/journal.pone.0278169">One strong predictor</a> for people distrusting science during the pandemic stood out: being distrusting of science in the first place. </p>
<h2>Understanding distrust</h2>
<p>Recent evidence has revealed that people who reject or distrust science are not especially well informed about it, but more importantly, they typically <a href="https://www.nature.com/articles/s41562-018-0520-3">believe that they do understand</a> the science. </p>
<p>This result has, over the past five years, been found over and over in studies investigating attitudes to a plethora of scientific issues, including <a href="https://doi.org/10.1016/j.socscimed.2018.06.032">vaccines</a> and <a href="https://www.nature.com/articles/s41562-018-0520-3">GM foods</a>. It also holds, <a href="https://doi.org/10.1371/journal.pbio.3001915">we discovered</a>, even when no specific technology is asked about. However, they may not apply to certain politicised sciences, such as <a href="https://www.science.org/doi/10.1126/sciadv.abo0038">climate change</a>.</p>
<p>Recent work also found that overconfident people who dislike science tend to <a href="https://doi.org/10.31234/osf.io/d5fz2">have a misguided belief</a> that theirs is the common viewpoint and hence that many others agree with them. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/564799/original/file-20231211-29-fgl8fe.jpg?ixlib=rb-1.1.0&rect=0%2C162%2C3721%2C2329&q=45&auto=format&w=1000&fit=clip"><img alt="Image of a protest of protest by covid-19 sceptics." src="https://images.theconversation.com/files/564799/original/file-20231211-29-fgl8fe.jpg?ixlib=rb-1.1.0&rect=0%2C162%2C3721%2C2329&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/564799/original/file-20231211-29-fgl8fe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/564799/original/file-20231211-29-fgl8fe.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/564799/original/file-20231211-29-fgl8fe.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/564799/original/file-20231211-29-fgl8fe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/564799/original/file-20231211-29-fgl8fe.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/564799/original/file-20231211-29-fgl8fe.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Covid protest in London.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/london-uk-april-24-2021-unite-1966630096">Devis M/Shutterstock</a></span>
</figcaption>
</figure>
<p>Other evidence suggests that some of those who reject science also gain psychological satisfaction by framing their alternative explanations in a manner that <a href="https://ec.europa.eu/info/live-work-travel-eu/coronavirus-response/fighting-disinformation/identifying-conspiracy-theories_en">can’t be disproven</a>. Such is often the nature of conspiracy theories – be it microchips in vaccines or COVID being caused by 5G radiation. </p>
<p>But the whole point of science is to examine and test theories that can be proven wrong – theories scientists call falsifiable. Conspiracy theorists, on the other hand, often reject information that doesn’t align with their preferred explanation by, as a last resort, questioning instead the <a href="https://commission.europa.eu/strategy-and-policy/coronavirus-response/fighting-disinformation/identifying-conspiracy-theories_en">motives of the messenger</a>. </p>
<p>When a person who trusts the scientific method debates with someone who doesn’t, they are essentially playing by different rules of engagement. This means it is hard to convince sceptics that they might be wrong. </p>
<h2>Finding solutions</h2>
<p>So what we can one do with this new understanding of attitudes to science?</p>
<p>The messenger is every bit as important as the message. Our work confirms many prior surveys showing that politicians, for example, aren’t trusted to communicate science, whereas university professors <a href="https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.3001915">are</a>. This should be kept in mind.</p>
<p>The fact that some people hold negative attitudes reinforced by a misguided belief that many others agree with them suggests a further potential strategy: tell people what the consensus position is. The advertising industry got there first. Statements such as “eight out ten cat owners say their pet prefers this brand of cat food” are popular.</p>
<p>A recent <a href="https://doi.org/10.1177/09567976221083219">meta-analysis</a> of 43 studies investigating this strategy (these were “randomised control trials” – the gold standard in scientific testing) found support for this approach to alter belief in scientific facts. In specifying the consensus position, it implicitly clarifies what is misinformation or unsupported ideas, meaning it would also address the problem that <a href="https://www.sfi.ie/resources/SFI-Science-in-Ireland-Barometer.pdf">half of people</a> don’t know what is true owing to circulation of conflicting evidence. </p>
<p>A complementary approach is to prepare people for the possibility of misinformation. Misinformation spreads fast and, unfortunately, each attempt to debunk it acts to bring the misinformation more into view. Scientists call this the “<a href="https://doi.org/10.1177/1529100612451018">continued influence effect</a>”. Genies never get put back into bottles. Better is to anticipate objections, or <a href="https://www.science.org/doi/10.1126/sciadv.abo6254">inoculate people</a> against the strategies used to promote misinformation. This is called “prebunking”, as opposed to debunking. </p>
<p>Different strategies may be needed in different contexts, though. Whether the science in question is established with a consensus among experts, such as climate change, or cutting edge new research into the unknown, such as for a completely new virus, matters. For the latter, explaining what we know, what we don’t know and what we are doing – and emphasising that results are provisional – <a href="https://www.nature.com/articles/d41586-020-03189-1">is a good way to go</a>. </p>
<p>By emphasising uncertainty in fast changing fields we can prebunk the objection that a sender of a message cannot be trusted as they said one thing one day and something else later.</p>
<p>But no strategy is likely to be 100% effective. We found that even with widely debated <a href="https://genetics.org.uk/wp-content/uploads/2018/06/Copy-of-Public-Perception-of-Genetics.pdf">PCR tests for COVID</a>, 30% of the public said they hadn’t heard of PCR. </p>
<p>A common quandary for much science communication may in fact be that it appeals to those already engaged with science. Which may be why you read this.</p>
<p>That said, the new science of communication suggests it is certainly worth trying to reach out to those who are disengaged.</p><img src="https://counter.theconversation.com/content/219579/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Laurence D. Hurst receives funding from The Evolution Education Trust. He is affiliated with The Genetics Society.
Dr Cristina Fonseca also contributed to this article as well as to some of the research mentioned that was funded by The Genetics Society.</span></em></p>People who are suspicious of science often assume they are understand it well – and that others agree with them.Laurence D. Hurst, Professor of Evolutionary Genetics at The Milner Centre for Evolution, University of BathLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2170592023-12-13T13:35:34Z2023-12-13T13:35:34ZHealth misinformation is rampant on social media – here’s what it does, why it spreads and what people can do about it<figure><img src="https://images.theconversation.com/files/564379/original/file-20231207-23-75o0yn.jpg?ixlib=rb-1.1.0&rect=62%2C26%2C5904%2C4070&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Media literacy is more essential than ever. </span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/illustration/myth-fake-news-and-facts-vector-illustration-royalty-free-illustration/1358189151?phrase=social+media+misinformation&searchscope=image%2Cfilm&adppopup=true">Wanlee Prachyapanaprai/iStock via Getty Images Plus</a></span></figcaption></figure><p>The global anti-vaccine movement and vaccine hesitancy that <a href="https://doi.org/10.1093/cid/ciaa433">accelerated during the COVID-19 pandemic</a> show no signs of abating.</p>
<p>According to a survey of U.S. adults, Americans in October 2023 were <a href="https://www.annenbergpublicpolicycenter.org/vaccine-confidence-falls-as-belief-in-health-misinformation-grows/">less likely to view approved vaccines as safe</a> than they were in April 2021. As vaccine confidence falls, health misinformation continues to spread like wildfire on social media and in real life.</p>
<p>I am a <a href="https://www.bu.edu/sph/profile/monica-wang/">public health</a> <a href="https://scholar.google.com/citations?user=5g6xyEMAAAAJ&hl=en">expert</a> in <a href="https://doi.org/10.1093/abm/kaaa088">health misinformation</a>, <a href="https://doi.org/10.1093/tbm/ibac096">science communication</a> and <a href="https://doi.org/10.1891/9780826180148">health behavior change</a>.</p>
<p>In my view, we cannot underestimate the <a href="https://doi.org/10.2105/AJPH.2020.305905">dangers of health misinformation</a> and the need to understand why it spreads and what we can do about it. Health misinformation is defined as any health-related claim that is false based on current scientific consensus. </p>
<h2>False claims about vaccines</h2>
<p>Vaccines are the No. 1 topic of misleading health claims. Some <a href="https://doi.org/10.3389%2Ffmicb.2020.00372">common myths about vaccines</a> include: </p>
<ul>
<li><p><strong>Their supposed link with human diagnoses of autism</strong>. Multiple studies have <a href="https://doi.org/10.1016/j.vaccine.2014.04.085">discredited this claim</a>, and it has been firmly refuted by the <a href="https://www.who.int/groups/global-advisory-committee-on-vaccine-safety/topics/mmr-vaccines-and-autism">World Health Organization</a>, the <a href="https://www.nationalacademies.org/based-on-science/vaccines-do-not-cause-autism">National Academies of Sciences, Engineering and Medicine</a>, the <a href="https://publications.aap.org/patiented/article-abstract/doi/10.1542/peo_document599/82016/Vaccines-Autism-Toolkit">American Academy of Pediatrics</a> and the <a href="https://www.cdc.gov/vaccinesafety/concerns/autism.html">Centers for Disease Control and Prevention</a>.</p></li>
<li><p><strong>Concerns with the COVID-19 vaccine leading to infertility</strong>. This connection has been debunked through a <a href="https://doi.org/10.1016%2Fj.vaccine.2022.09.019">systematic review and meta-analysis</a>, one of the most robust forms of synthesizing scientific evidence.</p></li>
<li><p><strong>Safety concerns about vaccine ingredients, such as thimerosal, aluminum and formaldehyde</strong>. Extensive studies have shown these ingredients are safe when used in <a href="https://www.aaaai.org/tools-for-the-public/conditions-library/allergies/vaccine-myth-fact">the minimal amounts contained in vaccines</a>.</p></li>
<li><p><strong>Vaccines as medically unnecessary to protect from disease</strong>. The development and dissemination of vaccines for life-threatening diseases such as smallpox, polio, measles, mumps, rubella and the flu has saved <a href="https://doi.org/10.1073%2Fpnas.1704507114">millions of lives</a>. It also played a critical role in historic <a href="https://doi.org/10.1073/pnas.1413559111">increases in average life expectancy</a> – from 47 years in 1900 in the U.S. to 76 years in 2023. </p></li>
</ul>
<p><div data-react-class="InstagramEmbed" data-react-props="{"url":"https://www.instagram.com/p/CX9WyO4s4kA","accessToken":"127105130696839|b4b75090c9688d81dfd245afe6052f20"}"></div></p>
<h2>The costs of health misinformation</h2>
<p>Beliefs in such myths have come at the highest cost. </p>
<p>An estimated 319,000 COVID-19 deaths that occurred between January 2021 and April 2022 in the U.S. <a href="https://globalepidemics.org/vaccinations/">could have been prevented</a> if those individuals had been vaccinated, according to a data dashboard from the Brown University School of Public Health. Misinformation and disinformation about COVID-19 vaccines alone have cost the U.S. economy an estimated <a href="https://doi.org/10.1093/tbm/ibac096">US$50 million to $300 million per day</a> in direct costs from hospitalizations, long-term illness, lives lost and economic losses from missed work.</p>
<p>Though vaccine myths and misunderstandings tend to dominate conversations about health, there is an <a href="https://doi.org/10.2196%2F17187">abundance of misinformation</a> on social media surrounding diets and eating disorders, smoking or substance use, chronic diseases and medical treatments. </p>
<p>My team’s research and that of others show that social <a href="https://doi.org/10.2196/43961">media platforms have become go-to sources</a> <a href="https://doi.org/10.2196%2F17917">for health information</a>, especially among adolescents and young adults.
However, many people are not equipped to maneuver the maze of health misinformation.</p>
<p>For example, an analysis of Instagram and TikTok posts from 2022 to 2023 by The Washington Post and the nonprofit news site The Examination found that the food, beverage and dietary supplement industries paid dozens of registered dietitian influencers to <a href="https://www.washingtonpost.com/wellness/2023/09/13/dietitian-instagram-tiktok-paid-food-industry/">post content promoting diet soda, sugar and supplements</a>, reaching millions of viewers. The dietitians’ relationships with the food industry were not always made clear to viewers. </p>
<p>Studies show that health misinformation spread on social media results in <a href="https://doi.org/10.1016%2Fj.vaccine.2022.09.046">fewer people getting vaccinated</a> and can also increase the risk of other health dangers such as <a href="https://www.scientificamerican.com/article/how-a-weight-loss-trend-on-tiktok-might-encourage-eating-disorders/">disordered eating</a> and <a href="https://doi.org/10.18297/tce/vol1/iss1/16">unsafe sex practices and sexually transmitted infections</a>. Health misinformation has even bled over into animal health, with a 2023 study finding that 53% of dog owners surveyed in a nationally representative sample report being <a href="https://doi.org/10.1016/j.vaccine.2023.08.059">skeptical of pet vaccines</a>.</p>
<h2>Health misinformation is on the rise</h2>
<p>One major reason behind the spread of health misinformation is <a href="https://www.pewresearch.org/science/2023/11/14/americans-trust-in-scientists-positive-views-of-science-continue-to-decline/">declining trust in science</a> and <a href="https://www.pewresearch.org/politics/2023/09/19/public-trust-in-government-1958-2023/">government</a>. Rising political polarization, coupled with <a href="https://doi.org/10.1080%2F08964289.2019.1619511">historical medical mistrust</a> among communities that have experienced and continue to experience <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4194634/">unequal health care treatment</a>, exacerbates preexisting divides.</p>
<p>The lack of trust is both fueled and reinforced by the way misinformation can spread today. Social media platforms allow people to <a href="https://doi.org/10.2105%2FAJPH.2020.305905">form information silos</a> with ease; you can curate your networks and your feed by unfollowing or muting contradictory views from your own and liking and sharing content that aligns with your existing beliefs and value systems. </p>
<p>By tailoring content based on past interactions, social media algorithms can unintentionally <a href="https://doi.org/10.1016/j.tics.2023.06.008">limit your exposure</a> to diverse perspectives and generate a fragmented and incomplete understanding of information. Even more concerning, a study of misinformation spread on Twitter analyzing data from 2006 to 2017 found that <a href="https://doi.org/10.1126/science.aap9559">falsehoods were 70% more likely to be shared</a> than the truth and spread “further, faster, deeper and more broadly than the truth” across all categories of information.</p>
<figure>
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<figcaption><span class="caption">The average kindergarten student sees about 70 media messages every day. By the time they’re in high school, teens spend more than a third of their day using media.</span></figcaption>
</figure>
<h2>How to combat misinformation</h2>
<p>The lack of robust and standardized regulation of misinformation content on social media places the difficult task of discerning what is true or false information on individual users. We scientists and research entities can also do better in communicating our science and rebuilding trust, as my colleague and I have <a href="https://www.bu.edu/articles/2023/rebuilding-public-trust-in-science/">previously written</a>. I also provide <a href="https://doi.org/10.1001/jamapediatrics.2023.5282">peer-reviewed recommendations</a> for the important roles that parents/caregivers, policymakers and social media companies can play. </p>
<p>Below are some steps that consumers can take to identify and prevent health misinformation spread: </p>
<ul>
<li><p><strong>Check the source.</strong> Determine the credibility of the health information by checking if the source is a reputable organization or agency such as the <a href="https://www.who.int">World Health Organization</a>, the <a href="https://www.nih.gov">National Institutes of Health</a> or the <a href="https://www.cdc.gov">Centers for Disease Control and Prevention</a>. Other credible sources include an established medical or scientific institution or a peer-reviewed study in an academic journal. Be cautious of information that comes from unknown or biased sources.</p></li>
<li><p><strong>Examine author credentials.</strong> Look for qualifications, expertise and relevant professional affiliations for the author or authors presenting the information. Be wary if author information is missing or difficult to verify.</p></li>
<li><p><strong>Pay attention to the date.</strong> Scientific knowledge by design is meant to evolve as new evidence emerges. Outdated information may not be the most accurate. Look for recent data and updates that contextualize findings within the broader field. </p></li>
<li><p><strong>Cross-reference to determine scientific consensus.</strong> Cross-reference information across multiple reliable sources. Strong consensus across experts and multiple scientific studies supports the validity of health information. If a health claim on social media contradicts widely accepted scientific consensus and stems from unknown or unreputable sources, it is likely unreliable. </p></li>
<li><p><strong>Question sensational claims.</strong> Misleading health information often uses sensational language designed to provoke strong emotions to grab attention. Phrases like “miracle cure,” “secret remedy” or “guaranteed results” may signal exaggeration. Be alert for potential conflicts of interest and sponsored content.</p></li>
<li><p><strong>Weigh scientific evidence over individual anecdotes.</strong> Prioritize information grounded in scientific studies that have undergone rigorous research methods, such as randomized controlled trials, peer review and validation. When done well with representative samples, the scientific process provides a reliable foundation for health recommendations compared to individual anecdotes. Though personal stories can be compelling, they should not be the sole basis for health decisions. </p></li>
<li><p><strong>Talk with a health care professional.</strong> If health information is confusing or contradictory, seek guidance from trusted health care providers who can offer personalized advice based on their expertise and individual health needs. </p></li>
<li><p><strong>When in doubt, don’t share.</strong> Sharing health claims without validity or verification contributes to misinformation spread and preventable harm.</p></li>
</ul>
<p>All of us can play a part in responsibly consuming and sharing information so that the spread of the truth outpaces the false.</p><img src="https://counter.theconversation.com/content/217059/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Monica Wang receives funding from the National Institutes of Health. </span></em></p>Studies show that health misinformation on social media has led to fewer people getting vaccinated and more lives lost to COVID-19 and other life-threatening diseases.Monica Wang, Associate Professor of Public Health, Boston UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2161272023-12-12T13:22:36Z2023-12-12T13:22:36ZCustomizing mRNA is easy, and that’s what makes it the next frontier for personalized medicine − a molecular biologist explains<figure><img src="https://images.theconversation.com/files/564366/original/file-20231207-25-2zr2cm.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C2000%2C1499&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">One of the advantages of mRNA is its scalability.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/illustration/genetic-engineering-dna-royalty-free-illustration/1310083278">DrAfter123/DigitalVision Vectors via Getty Images</a></span></figcaption></figure><p>While using mRNA as medicine is new, mRNA has been inside you for your entire life. The cells in your body create mRNAs that serve as instructions to make specific proteins you need to function. Researchers can create new mRNAs to correct those instructions when they aren’t working.</p>
<p>I am a <a href="https://scholar.google.com/citations?user=HQmZPBYAAAAJ&hl=en">molecular biologist</a> who studies how cells control their mRNAs to make the proteins they need, a basic question of how life works at the cellular level. While most scientists studying mRNAs are not creating new drugs, this fundamental understanding of how mRNA works <a href="https://theconversation.com/tenacious-curiosity-in-the-lab-can-lead-to-a-nobel-prize-mrna-research-exemplifies-the-unpredictable-value-of-basic-scientific-research-214770">laid the foundation</a> for other scientists to create effective mRNA medicines like <a href="https://theconversation.com/how-mrna-vaccines-from-pfizer-and-moderna-work-why-theyre-a-breakthrough-and-why-they-need-to-be-kept-so-cold-150238">COVID-19 vaccines</a>. </p>
<p>By tweaking these instructions, scientists can create powerful new medicines to repair a variety of problems in your cells.</p>
<h2>What does mRNA do?</h2>
<p>To understand what the mRNAs in your cells are doing for you, let’s start with its more well-known relative, DNA. </p>
<p>DNA is like a set of cookbooks full of different recipes, or genes, to make proteins. People make <a href="https://www.broadinstitute.org/blog/putting-proteins-their-place">about 100,000 different proteins</a> that are essential for <a href="https://theconversation.com/what-is-a-protein-a-biologist-explains-152870">normal function</a>, such as breaking down nutrients and carrying out other important chemical reactions.</p>
<p>When cells need to make one of those proteins, they don’t read the recipe directly from DNA. Instead, they make a copy in the form of a similar molecule – that’s <a href="https://www.genome.gov/genetics-glossary/messenger-rna">the mRNA</a>. The “m” stands for messenger, as mRNA contains the message, or recipe, that codes for a protein. About <a href="https://doi.org/10.1016/j.cell.2014.02.033">one-third of a cell’s energy</a> is devoted to maintaining the proteins you need, so cells are well equipped to recognize, use and then destroy mRNA once it’s no longer needed.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/564367/original/file-20231207-19-o117b3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Diagram illustrating flow of DNA transcription to RNA translation to protein" src="https://images.theconversation.com/files/564367/original/file-20231207-19-o117b3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/564367/original/file-20231207-19-o117b3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/564367/original/file-20231207-19-o117b3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/564367/original/file-20231207-19-o117b3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/564367/original/file-20231207-19-o117b3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/564367/original/file-20231207-19-o117b3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/564367/original/file-20231207-19-o117b3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">mRNA is the intermediary between DNA and protein.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/illustration/transcription-and-translation-dna-mrna-and-royalty-free-illustration/1474947465">Rujirat Boonyong/iStock via Getty Images</a></span>
</figcaption>
</figure>
<p>The language of mRNA is made of four <a href="https://www.genome.gov/genetics-glossary/Nucleotide">building blocks called nucleotides</a>, nicknamed A, U, C and G. The recipe to make a protein contains only three-letter words, meaning there are just 64 possible words. Scientists know exactly which words correspond to each protein building block, so they can easily read an mRNA recipe and know what protein will be made. Mutations in the DNA cookbook can alter or delete an mRNA recipe, leading to disease-causing mistakes in critical proteins.</p>
<h2>Why do mRNAs make great medicine?</h2>
<p>While mRNA has been within us all along, it took <a href="https://doi.org/10.1038/d41586-021-02483-w">decades of research</a> for scientists to understand how cells recognize mRNA and use it to make protein. But it eventually became clear that mRNA could be a powerful medical tool.</p>
<p>Since scientists understand how mRNAs code for proteins, they can easily create recipes for any protein. These recipes can be <a href="https://doi.org/10.1038/s41587-022-01430-y">edited to meet the needs</a> of the patient, whether this means providing a whole new mRNA recipe or tweaking an existing one to make a slight variation of the protein.</p>
<p>Producing mRNA treatments <a href="https://doi.org/10.1038/nrd.2017.243">is also scalable</a> because scientists can make large amounts of mRNA in the lab. The method to make one mRNA is the same for all mRNAs, unlike typical drugs where each compound has its own unique chemistry and requires different manufacturing methods. It’s like learning how to make risotto: Once you’ve learned the basic recipe, you can make endless variations.</p>
<p>Another benefit of using mRNAs as drugs are cells’ <a href="https://doi.org/10.1038/s41580-022-00512-8">natural ability to destroy them</a> when they aren’t needed. Since mRNAs aren’t permanent, doses can be easily changed to meet the changing needs of the patient.</p>
<h2>mRNA vaccines beyond COVID-19</h2>
<p>The <a href="https://theconversation.com/how-mrna-vaccines-from-pfizer-and-moderna-work-why-theyre-a-breakthrough-and-why-they-need-to-be-kept-so-cold-150238">COVID-19 vaccines</a> from Moderna and Pfizer-BioNTech are the first mRNA-based medicines to gain FDA approval. When these vaccines are injected into your arm, the mRNA is absorbed into some of your cells, which read the mRNA recipe and make the spike protein the virus uses to invade cells. Your immune system recognizes this spike protein as foreign and makes antibodies that prepare your body to attack the virus if you encounter it later.</p>
<p>These mRNA vaccines demonstrate the <a href="https://theconversation.com/how-can-scientists-update-coronavirus-vaccines-for-omicron-a-microbiologist-answers-5-questions-about-how-moderna-and-pfizer-could-rapidly-adjust-mrna-vaccines-172943">flexibility of mRNA-based therapies</a>. As the virus that causes COVID-19 mutates, new viral variants can evade existing antibodies and cause new waves of illness. However, scientists are able to sequence new mRNA recipes based on these variants and tweak the vaccine recipes to match them. Boosters containing these edited recipes teach your body to make new antibodies that target the latest versions of the viral spike protein.</p>
<figure>
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<figcaption><span class="caption">The Pfizer-BioNTech and Moderna COVID-19 vaccines were the first to use mRNA for immunization.</span></figcaption>
</figure>
<p>There are already clinical trials underway for other mRNA-based vaccines, including vaccines for <a href="https://theconversation.com/how-do-you-make-a-universal-flu-vaccine-a-microbiologist-explains-the-challenges-and-how-mrna-could-offer-a-promising-solution-195807">seasonal flu</a>, <a href="https://theconversation.com/how-mrna-and-dna-vaccines-could-soon-treat-cancers-hiv-autoimmune-disorders-and-genetic-diseases-170772">herpes</a> and <a href="https://theconversation.com/fdas-approval-of-the-worlds-first-vaccine-against-rsv-will-offer-a-new-tool-in-an-old-fight-4-questions-answered-205111">respiratory syncytial virus</a>. </p>
<p>There are also many more vaccines in earlier stages of development to combat diseases like <a href="https://www.forbes.com/sites/roberthart/2023/04/11/vaccines-for-lyme-disease-and-norovirus-moderna-working-on-shots-targeting-tick-borne-infection-and-vomiting-bug/">norovirus, Lyme disease</a>, <a href="https://doi.org/10.1016/S1473-3099(22)00764-2">Zika</a> and <a href="https://www.pfizerclinicaltrials.com/our-research/vaccines">shingles</a>. </p>
<h2>mRNA as treatment for disease</h2>
<p>The potential for mRNA-based medicine extends beyond vaccines to prevent infectious disease. One example is the <a href="https://theconversation.com/modernas-experimental-cancer-vaccine-treats-but-doesnt-prevent-melanoma-a-biochemist-explains-how-it-works-197003">use of mRNA to treat cancer</a>. </p>
<p>Some mRNA cancer treatments work like vaccines by training your immune system to specifically target cancer cells. As cancer cells grow, they rapidly gain mutations in many genes. Cancer vaccines contain mRNA recipes based on mutations commonly found in certain types of tumors. When injected into the body, the mRNAs from the vaccines allow normal cells to make those mutated proteins and broadcast them to the immune system, ramping up production of antibodies. These antibodies bind to cancer cells and mark them for immune attack.</p>
<p>Finding the <a href="https://theconversation.com/every-cancer-is-unique-why-different-cancers-require-different-treatments-and-how-evolution-drives-drug-resistance-199249">correct protein target for a given cancer</a> is essential. Ideally, the target is unique to the cancer cell so the immune system doesn’t attack healthy cells. The target protein should also be easy for the immune system to sense, making surface proteins good targets. Cancer vaccines, like <a href="https://doi.org/10.1038/s41586-020-2537-9">BioNTech’s BNT-111</a> for melanoma, target the most common cancer mutations in hope of helping many patients. But patients won’t benefit from the treatment if their cancer cells don’t have those particular mutations.</p>
<p>Because it is so easy to change the mRNA recipes, cancer vaccines can be part of a <a href="https://www.genome.gov/genetics-glossary/Personalized-Medicine">personalized medicine plan</a> where doctors sample a patient’s tumor, sequence key genes and adjust the mRNA treatment to include recipes specific to that patient’s cancer. Clinical trials using this <a href="https://www.mskcc.org/news/can-mrna-vaccines-fight-pancreatic-cancer-msk-clinical-researchers-are-trying-find-out">personalized approach for pancreatic cancer</a> are underway. </p>
<h2>The future of mRNA-based medicine</h2>
<p>Many diseases arise from cells making the wrong protein, a mutant version of protein or too little of the normal protein. If scientists can deliver a corrected version of the mRNA recipe to enough affected cells, then the mRNA will provide the means to make the proper protein.</p>
<p>Scientists are exploring the use of mRNA to treat <a href="https://spectrum.ieee.org/mrna-therapy-damaged-heart">heart disease</a>, <a href="https://theconversation.com/vaccination-to-prevent-dementia-new-research-suggests-one-way-viral-infections-can-accelerate-neurodegeneration-197009">neurodegenerative disease</a>, <a href="https://doi.org/10.1186/s41232-023-00285-3">bone loss</a> and much more. Although most of these studies are still very early in development, they provide hope for future treatments using mRNA for protein replacement therapies. </p>
<p>For example, one mRNA drug increases the <a href="https://www.nature.com/articles/s41467-019-08852-4">formation of new blood vessels</a>, which can improve <a href="https://www.healthline.com/health/diabetes/diabetes-and-wound-healing#what-leads-to-slow-healing">wound healing in diabetic patients</a> who have poor blood circulation and higher amputation risks. Another example is using mRNAs to treat <a href="https://clinicaltrials.gov/study/NCT04159103">propionic acidemia</a>, a disease where children have low levels of two liver proteins that normally prevent toxic byproducts from building up in the body.</p>
<p>The ability to easily customize and produce mRNA increases their potential as effective, personalized therapies – with fewer side effects – that can help many people.</p><img src="https://counter.theconversation.com/content/216127/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Angie Hilliker has received funding from the National Institutes of Health. </span></em></p>From COVID-19 vaccines to cancer treatments and beyond, the flexibility of mRNA-based therapies gives them the potential to prevent and treat many types of diseases.Angie Hilliker, Associate Professor of Biology, University of RichmondLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2195182023-12-11T12:37:21Z2023-12-11T12:37:21ZWhooping cough cases increasing in the UK – what you need to know<figure><img src="https://images.theconversation.com/files/564677/original/file-20231210-29-ny65no.jpg?ixlib=rb-1.1.0&rect=35%2C0%2C7904%2C5297&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/child-got-sick-virus-little-boy-1693664527">Zdan Ivan/Shutterstock</a></span></figcaption></figure><p>You may have read recent alarming reports of a cough that “<a href="https://www.thesun.co.uk/health/24974770/highly-contagious-cough-fractured-ribs-whooping-cough/">lasts 100 days</a>” is “<a href="https://www.mirror.co.uk/news/health/100-day-cough-quickly-spreading-31622932">quickly spreading across the UK</a>” and can “<a href="https://nypost.com/2023/12/07/lifestyle/100-day-cough-highly-contagious-infection-that-could-fracture-ribs-soars-250-in-uk/">fracture ribs</a>”. If you didn’t look beyond the headlines, you might have missed the fact that the reports are about <a href="https://www.nhs.uk/conditions/whooping-cough/">whooping cough</a>.</p>
<p>So, what is going on?</p>
<p>Whooping cough (or pertussis) is what is known in the UK as a “notifiable infectious disease”, which means any doctor who diagnoses a case has a legal duty to report the infection to the local authority. Notifications of whooping cough are indeed much higher this year, particularly in the five months since July than at any time during the previous three years. </p>
<p>In the 21 weeks to November 27, <a href="https://www.gov.uk/government/publications/notifiable-diseases-weekly-reports-for-2023">there were 716 notifications</a> compared with just 217 in the same period in 2022, 213 in 2021 and just 72 in 2020. That is more than a threefold rise this year compared with the previous year. </p>
<p>Like most respiratory infections, whooping cough was suppressed during the COVID years. Notifications for whooping cough this year are still <a href="https://www.gov.uk/government/publications/notifiable-diseases-weekly-reports-for-2023">markedly down on 2019</a> where there were 1,842 notifications over the same 21-week period. </p>
<p>What we are seeing now is a partial return to the pre-COVID situation and not an unprecedented surge in infections. (Although the reported cases represent only a <a href="https://bmcpublichealth.biomedcentral.com/articles/10.1186/1471-2458-14-147">fraction of all cases</a> in the community.)</p>
<p>The fact that whooping cough notifications are still relatively low should not distract from the fact that infections in the 2010s were still much <a href="https://www.gov.uk/government/publications/notifiable-diseases-historic-annual-totals">higher than in the previous decade</a>. Since the mid-1950s and the introduction of a vaccine, whooping cough was <a href="https://www.gov.uk/government/publications/pertussis-the-green-book-chapter-24">generally in decline</a> until this most recent decade. </p>
<h2>What is whooping cough?</h2>
<p>Whooping cough is a chest infection caused by the bacterium <em>Bordetella pertussis</em> – although another bacterium <em>Bordetella parapertussis</em> can also cause it. </p>
<p>The illness lasts for about six weeks or more and <a href="https://emedicine.medscape.com/article/967268-overview">progresses through three stages</a>. The first stage is very similar to a bad cold with a runny nose, sneezing and sore eyes. </p>
<p>The second phase, which starts after about two weeks, is characterised by bouts of intense coughing. Each bout can last several minutes and is occasionally followed by the loud whoop that gives the disease its name. Afterwards, a chronic cough can remain for several weeks.</p>
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<figcaption><span class="caption">What whooping cough sounds like.</span></figcaption>
</figure>
<p>Most people eventually make a full recovery, but in babies under three months old <a href="https://emedicine.medscape.com/article/967268-overview#a6">1% to 3% may die</a>. And most children under six months will require hospitalisation. </p>
<p>About one in 50 babies under one year will <a href="https://www.cdc.gov/pertussis/about/complications.html">suffer convulsions</a> and one in 150 (0.6%) will have encephalopathy (swelling of the brain). </p>
<p>Other even more serious neurological problems, such as paralysis and blindness, have been reported but are rare. In older children and adults, fainting, rib fractures, <a href="https://www.cdc.gov/pertussis/about/complications.html">pneumonia and urinary incontinence</a> can occur. </p>
<p>Antibiotics have limited value in <a href="https://onlinelibrary.wiley.com/doi/10.1002/ebch.1845">treating whooping cough</a>. They can reduce the time that the patient is infectious to others, but they have limited effect on preventing symptoms. </p>
<h2>How to avoid getting it</h2>
<p>There is an effective vaccine for whooping cough that in the UK is given in <a href="https://www.gov.uk/government/publications/routine-childhood-immunisation-schedule/routine-childhood-immunisations-from-february-2022-born-on-or-after-1-january-2020">combination with other vaccines</a> at eight, 12 and 16 weeks old. Then there is a booster shot given when the child is three years and four months. </p>
<p>The vaccine is also now recommended for pregnant women. This is not to protect the mother but to protect their baby during the first weeks of the child’s life before the first course of vaccine – when the infant would be at the highest risk of death.</p>
<p>Concerns about the safety of the vaccine, particularly during the 1970s, led to a significant fall in vaccine coverage and a re-emergence of whooping cough. </p>
<p>A committee of the US Institute of Medicine concluded that the evidence was “<a href="https://www.ncbi.nlm.nih.gov/books/NBK234367/">consistent with a causal relationship</a>” between the vaccine and acute encephalopathy, with a risk estimated at between zero and ten cases per million jabs administered. </p>
<p>However, subsequent studies suggested that many of the cases in the biggest study had a particular <a href="https://pubmed.ncbi.nlm.nih.gov/20447868/">genetic abnormality known as Dravet syndrome</a> and the whooping cough vaccine was merely bringing forward the date of onset of problems that would have happened anyway. </p>
<p>In any event, the studies reported above were of a time when whole-cell vaccines were being used (made from killed whole bacteria). Since 2004, whooping cough vaccines made with just parts of the bacterium (so-called acellular vaccine) have been used in the UK and these are associated with a <a href="https://pubmed.ncbi.nlm.nih.gov/12706690/">lower risk of side-effects</a>.</p>
<h2>Far from clear</h2>
<p>The recent increase in notifications of whooping cough, as mentioned above, is due to COVID suppression measures – lockdowns, mask-wearing and hand hygiene – coming to an end. But why there were more whooping cough cases during the years 2010 to 2019 compared with the previous decade is far from clear. </p>
<p>Vaccine coverage in the years before COVID up to 2019 was <a href="https://www.gov.uk/government/publications/pertussis-the-green-book-chapter-24">no lower than ten years previously</a>. <a href="https://karger.com/mpp/article/31/4/313/825084/Whole-Cell-and-Acellular-Pertussis-Vaccine">Possible explanations</a> include waning immunity, greater awareness of whooping cough among doctors (so more diagnoses), and improved laboratory diagnosis. </p>
<p>My take on the evidence is that the increasing infections in the years before COVID was down to the shift from whole-cell to acellular vaccine. Although the acellular vaccines cause fewer side-effects, they also generate <a href="https://karger.com/mpp/article/31/4/313/825084/Whole-Cell-and-Acellular-Pertussis-Vaccine">less powerful immunity</a>.</p>
<p>While both vaccines are highly effective at preventing severe disease, the acellular vaccine does not prevent mild infections that can be <a href="https://karger.com/mpp/article/31/4/313/825084/Whole-Cell-and-Acellular-Pertussis-Vaccine">infectious for others for as long</a>, so allowing the infection to continue to spread in the community. </p>
<p>The whole-cell pertussis vaccines were able to achieve herd immunity, which the acellular ones probably cannot. So the chance that young babies come into contact with an infectious older child or adult is now greater. </p>
<p>With the falling vaccination coverage in <a href="https://www.gov.uk/government/publications/pertussis-immunisation-in-pregnancy-vaccine-coverage-estimates-in-england-october-2013-to-march-2014/pertussis-vaccination-coverage-for-pregnant-women-in-england-january-to-march-and-annual-coverage-2021-to-2022">pregnant women</a> this puts babies at risk in their most vulnerable first weeks of life.</p><img src="https://counter.theconversation.com/content/219518/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Paul Hunter consults for the World Health Organization. He receives funding from National Institute for Health Research and has received funding from the World Health Organization and the European Regional Development Fund.</span></em></p>Antibiotics aren’t very effective against it, but we do have a vaccine.Paul Hunter, Professor of Medicine, University of East AngliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2161392023-11-21T13:26:58Z2023-11-21T13:26:58ZHow do viruses get into cells? Their infection tactics determine whether they can jump species or set off a pandemic<figure><img src="https://images.theconversation.com/files/560185/original/file-20231117-23-zg89fr.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C2309%2C1299&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Surface proteins on a virus enable it to attach to and get inside a cell to start replicating.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/new-omicron-sub-variant-bq-1-1-royalty-free-image/1435658319">koto_feja/E+ via Getty Images</a></span></figcaption></figure><p>COVID-19, flu, mpox, noroviral diarrhea: How do the viruses that cause these diseases actually infect you?</p>
<p>Viruses <a href="https://www.khanacademy.org/science/biology/biology-of-viruses/virus-biology/a/intro-to-viruses">cannot replicate on their own</a>, so they must infect cells in your body to make more copies of themselves. The life cycle of a virus can thus be roughly described as: get inside a cell, make more virus, get out, repeat. </p>
<p>Getting inside a cell, or <a href="https://doi.org/10.1016/j.jmb.2018.03.034">viral entry</a>, is the part of the cycle that most vaccines target, as well as a key barrier for viruses jumping from one species to another. <a href="https://scholar.google.com/citations?user=OQ7vzu0AAAAJ&hl=en">My lab</a> and many others study this process to better anticipate and combat emerging viruses.</p>
<h2>How viruses enter cells</h2>
<p>Different viruses travel into the body in <a href="https://www.oregon.gov/oha/ph/diseasesconditions/communicabledisease/pages/transmission.aspx">various ways</a> – via airborne droplets, on food, through contact with mucous membranes or through injection. They typically first infect host cells near their site of entry – the cells lining the respiratory tract for most airborne viruses – then either remain there or spread throughout the body.</p>
<p>Viruses <a href="https://doi.org/10.1016/j.jmb.2018.06.024">recognize specific proteins or sugars</a> on host cells and stick to them. Each virus gets only one shot at putting its genome inside a cell – if their entry machinery misfires, they risk becoming inactivated. So they <a href="https://doi.org/10.1016/j.virol.2015.02.037">use several mechanisms</a> to prevent triggering entry prematurely.</p>
<p>After the virus binds to the cell, specific molecules on the cell’s surface or within the cell’s recycling machinery <a href="https://doi.org/10.1111/tra.12389">activate viral coat proteins for entry</a>. An example is the SARS-CoV-2 spike that COVID-19 vaccines target. These proteins need to modify the cell membrane to allow the viral genome to get through without killing the cell in the process. Different viruses use different tricks for this, but most work like cellular secretion – how cells release materials into their environment – in reverse. Specialized viral proteins help <a href="https://doi.org/10.1146/annurev-virology-111821-093413">merge the membranes of the virus and the cell</a> together and release the viral core into the interior of the cell.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/i__QSjC-pt0?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">This animation depicts HIV fusing its membrane with a cell in order to release its contents inside.</span></figcaption>
</figure>
<p>At this point, the viral genome can enter the cell and <a href="https://doi.org/10.1016%2FB978-0-12-800947-5.00004-1">start replicating</a>. Some viruses use only the cell’s machinery to replicate, while others carry along portions of their own replication machinery and borrow some parts from the cell. After replicating their genomes, viruses assemble the components required to make new viruses.</p>
<p>Two central questions scientists are studying about viral entry are how your body’s defenses can disrupt it and what determines whether a virus from other species can infect people.</p>
<h2>Immune defenses against viruses</h2>
<p>Your body has a multilayered defense system against viral threats. But the part of your immune system called the <a href="https://doi.org/10.1016/j.jaci.2009.12.980">antibody response</a> is generally thought to be most effective at <a href="https://doi.org/10.1016/j.immuni.2022.10.017">sterilizing immunity</a> – preventing an infection from taking hold in the first place as opposed to just limiting its scope and severity. </p>
<p>For many viruses, antibodies target the part of the virus that binds to cells. This is the case not just for current COVID-19 vaccines but also the majority of immunity against influenza, whether from vaccines or from prior infection. </p>
<p>However, some antibodies target the entry machinery instead: Rather than preventing the virus from sticking, they prevent the virus from working altogether. Such antibodies are often harder for the viruses to escape from but are difficult to reproduce with vaccines. For that reason, developing antibodies that inhibit cell entry has the been the goal of many <a href="https://doi.org/10.1016/j.coviro.2016.02.002">next-generation vaccine efforts</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/551885/original/file-20231003-25-cv0pnn.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Diagram of the mechanisms of four classes of HIV antivirals" src="https://images.theconversation.com/files/551885/original/file-20231003-25-cv0pnn.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/551885/original/file-20231003-25-cv0pnn.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=496&fit=crop&dpr=1 600w, https://images.theconversation.com/files/551885/original/file-20231003-25-cv0pnn.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=496&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/551885/original/file-20231003-25-cv0pnn.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=496&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/551885/original/file-20231003-25-cv0pnn.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=623&fit=crop&dpr=1 754w, https://images.theconversation.com/files/551885/original/file-20231003-25-cv0pnn.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=623&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/551885/original/file-20231003-25-cv0pnn.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=623&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">This diagram shows how four different classes of antiviral drugs inhibit HIV. One stops viruses from entering cells, and three inhibit different viral enzymes.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:HIV-drug-classes.svg">Thomas Splettstoesser/Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<h2>Species-hopping and pandemics</h2>
<p>The other key question researchers are asking about viral entry is <a href="https://www.cdc.gov/flu/pandemic-resources/national-strategy/risk-assessment.htm">how to tell when</a> a virus from another species poses a threat to people. This is particularly important because many viruses are first identified in animals such as bats, birds and pigs before they spread to humans, but it’s unclear which ones may cause a pandemic.</p>
<p>The part of viruses that stick to human cells varies the most across species, while the part that gets the virus into cells <a href="https://doi.org/10.1016/bs.aivir.2016.08.004">tends to stay mostly the same</a>. Many researchers have thought that viruses changing in ways that bind better to human cells, like influenza viruses that bind to cells in the nose and throat, are some of the most important warning signs for pandemic risk. </p>
<p>However, coronaviruses – the family of viruses containing SARS-CoV-2 – are prompting re-examination of that idea. This is because several animal coronaviruses can actually <a href="https://doi.org/10.1038/s41564-020-0688-y">bind to human cells</a>, but only a few seem to be able to transmit well between people.</p>
<p>Only time will tell whether researchers need to broaden their pandemic prevention horizons or if their current prioritization of risky viruses is correct. The one grim reality of pandemic research, like earthquake research, is that there will always be another one – we just don’t know when or where, and we <a href="https://www.niaid.nih.gov/sites/default/files/pandemic-preparedness-plan.pdf">want to be ready</a>.</p><img src="https://counter.theconversation.com/content/216139/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Peter Kasson receives funding from the National Institutes of Health, the National Science Foundation, the Commonwealth Health Research Board, and the Knut and Alice Wallenberg Foundation. He is affiliated with the University of Virginia, Uppsala University, and Georgia Institute of Technology.</span></em></p>Viruses can get into cells in several ways. Figuring out how to stop them from entering in the first place is a key to developing better vaccines and stopping future pandemics.Peter Kasson, Professor of Molecular Physiology and Biomedical Engineering, University of VirginiaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2171462023-11-21T13:09:29Z2023-11-21T13:09:29ZMalaria: two groundbreaking vaccines have been developed, but access and rollout are still big stumbling blocks<p><em>The approval of two malaria vaccines – the RTS,S/AS01 vaccine in 2021 and the R21/Matrix-MTM vaccine in 2023 – will help control, and eventually help eradicate, a disease that causes more than <a href="https://www.who.int/news-room/fact-sheets/detail/malaria#:%7E:text=Disease%20burden&text=cases%20in%202020.-,The%20estimated%20number%20of%20malaria%20deaths%20stood%20at%20619%20000,63%20000%20more%20malaria%20deaths.">600,000 deaths</a> annually.</em></p>
<p><em>Nearly <a href="https://www.who.int/initiatives/malaria-vaccine-implementation-programme#:%7E:text=The%20first%20malaria%20vaccine%2C%20RTS,Programme%2C%20MVIP%2C%20since%202019.">2 million children</a> in Ghana, Kenya and Malawi have been vaccinated with the <a href="https://www.who.int/initiatives/malaria-vaccine-implementation-programme">RTS,S/AS01</a> vaccine. It will be rolled out to more African countries from early next year.</em></p>
<p><em>The second vaccine, <a href="https://www.ox.ac.uk/news/2023-10-02-oxford-r21matrix-m-malaria-vaccine-receives-who-recommendation-use-paving-way-global">R21/Matrix-MTM</a>, approved by the World Health Organization in October, will be ready for rollout in <a href="https://www.who.int/news/item/02-10-2023-who-recommends-r21-matrix-m-vaccine-for-malaria-prevention-in-updated-advice-on-immunization#:%7E:text=High%20efficacy%20when%20given%20just,following%20a%203%2Ddose%20series.">mid-2024</a>.</em></p>
<p><em>Rose Leke, winner of the <a href="https://virchowprize.org/2023-laureate/">2023 Virchow Prize </a>for her lifetime achievement in strengthening global health and a prominent voice in vaccine protocols, sheds light on the breakthroughs.</em></p>
<h2>Why are the vaccines significant for Africa?</h2>
<p>There are about <a href="https://theconversation.com/we-could-eradicate-malaria-by-2040-says-expert-after-revolutionary-vaccine-is-approved-by-who-214798">40 million children</a> born every year in malaria areas in Africa who would benefit from a vaccine. </p>
<p>The RTS,S/AS01 vaccine reduces malaria deaths by <a href="https://www.who.int/news/item/06-10-2021-who-recommends-groundbreaking-malaria-vaccine-for-children-at-risk">30%</a> and is especially important for children, who are most at risk from malaria. If you had 100 children who would die from severe malaria, you could save 30. </p>
<p>Mothers who have had their children vaccinated in the pilot phase have expressed appreciation for the vaccine because it has prevented their children from dying of <a href="https://www.who.int/news-room/feature-stories/detail/mothers-in-malawi-value-the-first-malaria-vaccine">severe malaria</a>. </p>
<p>The second vaccine, <a href="https://www.who.int/news/item/02-10-2023-who-recommends-r21-matrix-m-vaccine-for-malaria-prevention-in-updated-advice-on-immunization">R21/Matrix-M</a>, is highly effective, reducing cases of malaria by 75%. <a href="https://theconversation.com/we-could-eradicate-malaria-by-2040-says-expert-after-revolutionary-vaccine-is-approved-by-who-214798">Hundreds of millions</a> of doses of this vaccine can be produced each year. </p>
<p>It will be ready for rollout as early as <a href="https://www.who.int/news/item/02-10-2023-who-recommends-r21-matrix-m-vaccine-for-malaria-prevention-in-updated-advice-on-immunization#:%7E:text=High%20efficacy%20when%20given%20just,following%20a%203%2Ddose%20series">mid-2024</a></p>
<p>These two vaccines are new tools, but they have to be used with the other measures we have against malaria. These include bed nets and the administration of antimalarials to children at the highest risk of malaria at specific times throughout the year. </p>
<p>If we add the vaccine on top of these measures effectively, we may move further towards malaria <a href="https://theconversation.com/we-could-eradicate-malaria-by-2040-says-expert-after-revolutionary-vaccine-is-approved-by-who-214798">elimination</a>. </p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/we-could-eradicate-malaria-by-2040-says-expert-after-revolutionary-vaccine-is-approved-by-who-214798">'We could eradicate malaria by 2040' says expert after revolutionary vaccine is approved by WHO</a>
</strong>
</em>
</p>
<hr>
<h2>How can all communities benefit?</h2>
<p>There is great demand for malaria vaccines. The demand is estimated to be <a href="https://cdn.who.int/media/docs/default-source/immunization/mvip/first_malaria_vaccine_allocation_explained_may2023.pdf?sfvrsn=248c4624_4">40 to 60 million doses</a> by 2026 alone. </p>
<p><a href="https://www.gavi.org/">Gavi</a>, the Vaccine Alliance, has given the nod to Benin, the Democratic Republic of Congo and Uganda among 12 countries in Africa to receive the first doses of the vaccine. They will be allocated a total of <a href="https://cdn.who.int/media/docs/defaultsource/immunization/mvip/first_malaria_vaccine_allocation_explained_may2023.pdf?sfvrsn=248c4624_4">18 million</a> vaccines for the period up to 2025. </p>
<p>Gavi is an international organisation created in 2000 to improve access to new and underused vaccines for children living in the world’s poorest countries.</p>
<p>So as you can see demand has been far greater than supply. When we had just one vaccine, the RTS/S, quantities were limited, and the WHO had to develop an equitable framework for the distribution of the limited doses. </p>
<p>Countries were categorised. Those in category 1 were most in need and the first to be vaccinated.</p>
<p>I was a little bit worried about this. If somebody came to my country, and they were vaccinating in a category 1 village and 20km away, in a category 2 village, a child could not get the vaccine, that would cause a problem socially and even politically. </p>
<p>I was <a href="https://cdn.who.int/media/docs/default-source/immunization/mvip/framework-for-allocation-of-limited-malaria-vaccine-supply.pdf?sfvrsn=35b12e4_2&download=true">co-chair</a> of the WHO panel looking into this. We spent a lot of time on the <a href="https://cdn.who.int/media/docs/default-source/immunization/mvip/first_malaria_vaccine_allocation_explained_may2023.pdf?sfvrsn=248c4624_4">framework</a>, trying to work out who gets it and who doesn’t. </p>
<p>These are the principles we followed:</p>
<ul>
<li><p>Areas of greatest need: where the malaria disease burden in children is highest and the risk of death is highest.</p></li>
<li><p>Where the expected health impact is greatest: where most lives can be saved with the limited available doses.</p></li>
<li><p>Countries that committed to fairness in their vaccination programmes.</p></li>
</ul>
<p>One of the criteria was that once the new vaccine was introduced through routine public health services in a certain area, <a href="https://cdn.who.int/media/docs/default-source/immunization/mvip/first_malaria_vaccine_allocation_explained_may2023.pdf?sfvrsn=248c4624_4">continuous and sustainable</a> access needed to be maintained. </p>
<h2>Why is local manufacturing so important?</h2>
<p>During <a href="https://www.wipo.int/wipo_magazine/en/2022/04/article_0005.html">COVID,</a> we saw that Africa was at the back of the queue. The best way to secure supply is to make it yourself.</p>
<p>That’s why vaccine manufacturing in Africa is one of the <a href="https://africacdc.org/news-item/a-new-deal-for-african-health-security/">Africa Centres for Disease Control’s</a> biggest priorities. </p>
<p>I hope that in my lifetime I will see some of these vaccines being produced on the continent.</p>
<h2>Not all people want the vaccinations, do they?</h2>
<p>My experience in Africa is that routine immunisation coverage is still quite <a href="https://www.afro.who.int/health-topics/immunization#:%7E:text=Approximately%201%20in%205%20African,VPDs">low</a>. Now we’re going to add this new malaria vaccine. If we have low vaccination rates, we will never get the impact we want. </p>
<p>So we always have to encourage mothers to take the children for vaccinations, and vaccine <a href="https://www.researchgate.net/publication/366944062_The_impact_of_information_sources_on_COVID-19_vaccine_hesitancy_and_resistance_in_sub-Saharan_Africa">hesitancy</a> should really be stopped. </p>
<p>There’s the <a href="https://journals.co.za/doi/full/10.10520/ejc-ajgd_v10_n1_1_a4">belief</a> that these foreign vaccines are coming to kill the <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8115834/">children</a>. But what <em>haven’t</em> we imported? Is it milk? Is it soap? Is it sardines? </p>
<p>Why is it only with vaccines that people have these theories? </p>
<p>Vaccines have been so effective, the<a href="https://www.afro.who.int/health-topics/immunization"> impact</a> on the African continent has been so great.</p>
<p>Most of us, even me and you, might have been gone without vaccines. We need to inform people to get rid of this vaccine hesitancy that we have all over the continent.</p>
<p><em>This article is part of a media partnership between The Conversation Africa and the 2023 Conference on Public Health in Africa.</em></p><img src="https://counter.theconversation.com/content/217146/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Rose Leke does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>The past two years have seen groundbreaking advances in the fight against malaria with the development of two vaccines. But demand far exceeds supply, so rollouts need to be carefully managed.Rose Leke, Professor of Immunology and Parasitology, Faculty of Medicine and Biomedical Sciences, Université de Yaounde 1Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2178742023-11-17T17:18:19Z2023-11-17T17:18:19ZChickenpox vaccine recommended for NHS – here’s why a jab is better than getting the disease<figure><img src="https://images.theconversation.com/files/560163/original/file-20231117-15-13qh08.jpg?ixlib=rb-1.1.0&rect=0%2C4%2C3264%2C2438&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">If the vaccine is offered, children would be given two doses.
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/doctor-giving-child-injection-26170495">sergei telegin/ Shutterstock</a></span></figcaption></figure><p>The <a href="https://www.gov.uk/government/publications/childhood-varicella-vaccination-programme-jcvi-advice-14-november-2023/jcvi-statement-on-a-childhood-varicella-chickenpox-vaccination-programme">chickenpox vaccine</a> is already offered as part of childhood immunisation programmes in <a href="https://www.gov.uk/government/news/jcvi-recommends-chickenpox-vaccine-in-childhood-immunisation-programme#:%7E:text=If%20approved%2C%20it%20would%20bring,programme%20in%20place%20since%201995.">several countries</a>, including Canada, the US, Australia and New Zealand. Now the UK government’s Joint Committee on Vaccination and Immunisation (JCVI) has recommended it be included as part of the routine immunisations children receive in the UK.</p>
<p>Not only does evidence from these countries show us the chickenpox vaccine is safe, it also shows us just how effective the vaccine can be – and why it should be introduced in the UK. </p>
<p>In the US for example, where the vaccine was introduced as a routine childhood immunisation in 1995, <a href="https://www.idsociety.org/news--publications-new/articles/2022/chickenpox-now-rare-in-u.s.-due-to-routine-vaccination/">cases have fallen by 97%</a>. Indeed, the chickenpox vaccine prevents almost four million cases, 10,500 hospitalisations and 100 deaths from chickenpox there every year. </p>
<p>Vaccinating kids against chickenpox would not only protect them against mild cases of the virus, but it would also prevent more severe cases and the rare complications that can sometimes happen. This move could be especially beneficial now, given immunity to chickenpox is significantly lower than normal <a href="https://www.gov.uk/government/publications/childhood-varicella-vaccination-programme-jcvi-advice-14-november-2023/jcvi-statement-on-a-childhood-varicella-chickenpox-vaccination-programme">due to the pandemic</a>. </p>
<p>If rolled out soon, it would protect more children from contracting chickenpox, improve immunity within the population and lower case numbers – which may also protect adults who haven’t been exposed before from contracting the virus. </p>
<p>And not only would it protect children and their health now, it would also have many knock-on benefits for their health in the future.</p>
<h2>Offering protection</h2>
<p>Chickenpox is a highly infectious disease caused by the <a href="https://www.cdc.gov/chickenpox/hcp/index.html#:%7E:text=Varicella%20(chickenpox)%20is%20an%20acute,ganglia">varicella zoster virus</a>.</p>
<p>The chickenpox vaccine protects against the varicella virus. If it was included as part of routine childhood vaccination programmes, children would be given two doses when they’re aged 12 months and 18 months. The JCVI has also recommended that older children be offered the vaccine as part of a catch-up programme. </p>
<p>While chickenpox is mostly contracted by young children, the virus can infect anyone of any age. Most cases in children are mild, causing extremely itchy fluid-filled blisters, along with a fever and generally feeling unwell. The infection typically lasts four to seven days.</p>
<p>But some children will develop complications that require hospitalisation – such as inflammation in the <a href="https://www.hopkinsmedicine.org/health/conditions-and-diseases/chickenpox">lungs or the brain</a>. While these complications can occur in any child, the risk of <a href="https://www.clinicalguidelines.scot.nhs.uk/nhsggc-guidelines/nhsggc-guidelines/infectious-disease/varicella-zoster-infection-chickenpox-management-in-children/">severe infection</a> is higher in children who are immunocompromised or have underlying medical conditions. </p>
<p>Along with the risk of complications, being infected with chickenpox can increase a person’s risk of developing shingles later in life. Approximately <a href="https://www.gov.uk/government/publications/shingles-vaccination-for-adults-aged-70-or-79-years-of-age-a5-leaflet/vaccination-against-shingles-guide-from-september-2023">one in five people</a> who have had chickenpox will develop shingles later in life.</p>
<figure class="align-center ">
<img alt="Patches of the shingles rash on a woman's arm." src="https://images.theconversation.com/files/560164/original/file-20231117-15-m7yjxy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/560164/original/file-20231117-15-m7yjxy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/560164/original/file-20231117-15-m7yjxy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/560164/original/file-20231117-15-m7yjxy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/560164/original/file-20231117-15-m7yjxy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/560164/original/file-20231117-15-m7yjxy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/560164/original/file-20231117-15-m7yjxy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The chickenpox vaccine may also protect against developing shingles later in life.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/woman-shingles-on-skin-she-feels-2344606969">aslysun/ Shutterstock</a></span>
</figcaption>
</figure>
<p>This is due to the fact that <a href="https://www.cdc.gov/shingles/hcp/clinical-overview.html">following infection</a>, the virus travels to the sensory nerve ganglia, where it remains quiet and doesn’t cause any infection for decades. But it can reactivate as shingles later in life – normally when a person is older and their immune system is weakened. This results in a rash that can cause significant pain. In around 10-18% of cases, this rash can remain for the <a href="https://www.cdc.gov/shingles/about/complications.html">rest of their life</a>.</p>
<h2>Why vaccination is better</h2>
<p>The chickenpox vaccine is a live vaccine. This means it contains a small amount of weakened varicella virus, which is administered by injection into the upper arm.</p>
<p>This switches on your immune system to produce antibodies to the virus, which prevents the virus from being able to establish an infection when you’re exposed to the real thing. </p>
<p>The vaccine is <a href="https://www.cdc.gov/vaccines/vpd/varicella/hcp/about-vaccine.html">around 90% effective</a> in protecting against infection. It’s most protective when children are given two doses of the vaccine. </p>
<p>Some may wonder whether immunity from the vaccine is better than immunity from the infection itself. It’s important to point out that in both instances, the immune system is activated by the virus and will generate specific antibodies to protect against it in the future. This means the next time a person is exposed to the chickenpox virus, their antibodies will block it, preventing an infection.</p>
<p>While the vaccine contains only a small amount of weakened virus (which is not capable of causing infection), your immune system still sees it in the same way as it would if you caught the virus from someone else. You still generate an immune response, and you still get protection.</p>
<p>The significant advantage of generating immunity using the vaccine is that you don’t have to get sick with chickenpox, which could have serious side effects. And, the virus doesn’t stay in your body for decades with the risk of being <a href="https://www.cdc.gov/shingles/hcp/clinical-overview.html">activated as shingles</a> later in life.</p>
<p>Apart from the health benefits of vaccinating children, it may also have other benefits – such as preventing time out of school, which will be good for the child’s education.</p>
<p>If this new recommendation comes into force, it will be the beginning of an era where chickenpox infections in children will become the exception rather than the norm. We have a safe vaccine that can prevent a childhood illness which, in some, can cause severe complications. It makes sense that we should be using it.</p><img src="https://counter.theconversation.com/content/217874/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Christine Loscher does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>In one country where the chickenpox vaccine is already routine, cases have fallen by 97% since it was first introduced.Christine Loscher, Professor of Immunology, Dublin City UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2168202023-11-10T01:03:36Z2023-11-10T01:03:36ZWe’re in a new COVID wave. What can we expect this time?<figure><img src="https://images.theconversation.com/files/558289/original/file-20231108-21-f5uskt.jpg?ixlib=rb-1.1.0&rect=65%2C139%2C5398%2C3497&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/young-woman-face-mask-walking-through-1685691631">Shutterstock</a></span></figcaption></figure><p>Australia is now into its <a href="https://www.abc.net.au/news/2023-11-02/nsw-sydney-covid-christmas-fresh-wave/103051190">next COVID wave</a>. We’ve seen hints of this for a while. Case numbers and indicators of severe disease began rising in Victoria in August. But it has taken several months for a consistent pattern to emerge across Australia. </p>
<p>Now we see evidence of this new wave via <a href="https://www.health.vic.gov.au/sites/default/files/2023-11/victorian-covid-19-surveillance-report-03-november-2023.pdf">wastewater surveillance</a> for traces of SARS-CoV-2, the virus that causes COVID. We also see <a href="https://www.health.gov.au/topics/covid-19/weekly-reporting">rises</a> in COVID-related hospital admissions and antiviral prescriptions. Compared to past waves, this one has built up slowly and over a longer period.</p>
<p>Here’s what we know about this new wave and what to expect over the coming weeks.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/a-covid-inquiry-has-been-announced-but-is-covid-still-a-thing-do-i-need-a-booster-213469">A COVID inquiry has been announced. But is COVID still a thing? Do I need a booster?</a>
</strong>
</em>
</p>
<hr>
<h2>How do we know we’re in a new COVID wave?</h2>
<p>In earlier waves, when more people were testing for COVID and reporting their results, we were more confident case numbers were a reasonable reflection of how COVID was tracking.</p>
<p>However, now, a more useful indicator for COVID nationally is to look at trends in the number of prescriptions for the antiviral medications ritonavir (Paxlovid) and molnupiravir (Lagevrio) on the Pharmaceutical Benefits Scheme (PBS). </p>
<p>In the graph below, which is drawn from <a href="https://www.health.gov.au/topics/covid-19/weekly-reporting">national prescribing data</a>, you can clearly see script numbers rising.</p>
<p><iframe id="3d26e" class="tc-infographic-datawrapper" src="https://datawrapper.dwcdn.net/3d26e/1/" height="400px" width="100%" style="border: none" frameborder="0"></iframe></p>
<h2>When will we hit the peak?</h2>
<p>It has become more difficult to predict the size and timing of the peak. Reduced access to COVID testing and fewer requirements or opportunities to report test results, combined with the slow growth rate for this wave, give a wider range of possibilities. </p>
<p>The wave is also likely to differ between states and territories, as some got off to a later start. </p>
<p>However, given the wave’s slow growth rate and further increases in hybrid immunity (immunity from both vaccination and infection) over 2023, it’s reasonable to expect this to be the smallest Omicron wave so far. </p>
<p>We also expect it will be over by early in the summer holiday period. That’s when rates of community contact decline significantly, as work and school contacts are much reduced. That means fewer opportunities for the virus to spread between networks of family and friends.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/ah-memories-of-2020-why-its-important-to-remember-our-covid-holidays-good-or-bad-150061">Ah, memories of 2020. Why it's important to remember our COVID holidays, good or bad</a>
</strong>
</em>
</p>
<hr>
<h2>Why now?</h2>
<p>It’s unlikely this latest COVID wave stems from changes in behaviour. People are generally out and about, fewer people are wearing masks in public. But we don’t see any dramatic shifts in this type of behaviour in 2023 compared with 2022.</p>
<p>It’s not a seasonal cause, given respiratory viruses tend to spread better in winter, when we’re cooped up indoors with others.</p>
<p>It’s unlikely it’s our <a href="https://www.medrxiv.org/content/10.1101/2023.08.26.23294679v1">waning immunity</a> from infection or vaccination that’s prompting these successive waves.</p>
<p>Instead, we’re seeing the result of a constantly mutating virus. Successful SARS-CoV-2 variants are gradually acquiring mutations. Some of these changes reduce the ability of existing antibodies to bind to and neutralise the virus. So it appears it’s still the “immune escape” variants that are behind these latest waves.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/with-a-covid-variant-soup-looming-new-zealand-urgently-needs-another-round-of-vaccine-boosters-193616">With a COVID 'variant soup' looming, New Zealand urgently needs another round of vaccine boosters</a>
</strong>
</em>
</p>
<hr>
<h2>Which variants are to blame?</h2>
<p>The primary viral lineage in Australia this year has been XBB. Over the past six months, its two most influential mutations have been:</p>
<ul>
<li><p>the F456L mutation that led to the rise of EG.5.1, also known as Eris</p></li>
<li><p>more recently, the paired “FLip” mutations F456L+L455F. We see these in offspring of Eris and in much-less closely related lineages. This is a clear sign these mutations help the virus spread better.</p></li>
</ul>
<p>Both the single and paired mutations make existing antibodies less effective at blocking SARS-CoV-2 from binding to critical receptors on our cells. This increases our susceptibility to infection.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1689763022573916169"}"></div></p>
<p>The novel BA.2.86 lineage – colloquially known as Pirola – was first reported in Denmark in August and has many unique mutations. It has not been influential so far in this wave in Australia. But it has continued to evolve. And we may see it play a much bigger role in Australia in 2024.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/how-evasive-and-transmissible-is-the-newest-omicron-offshoot-ba-2-86-that-causes-covid-19-4-questions-answered-212453">How evasive and transmissible is the newest omicron offshoot, BA.2.86, that causes COVID-19? 4 questions answered</a>
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</em>
</p>
<hr>
<h2>Who is most at risk during this COVID wave?</h2>
<p>Since the start of the pandemic, rates of COVID-related death and severe disease have greatly declined. That’s due to <a href="https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(22)00801-5/fulltext">widespread</a> vaccination and hybrid immunity, and a major change in the Omicron variant that’s made the virus less-likely to <a href="https://pubmed.ncbi.nlm.nih.gov/35104837/">infect the lung</a>.</p>
<p>However, provisional statistics show there have been about <a href="https://www.abs.gov.au/statistics/health/causes-death/provisional-mortality-statistics/latest-release">3,000</a> registered COVID deaths in Australia from January to July 2023.</p>
<p>Older people and those with weaker immune systems are expected to remain at <a href="https://www.sciencedirect.com/science/article/pii/S2468266723000798">greatest risk</a> of developing severe COVID during this current wave.</p>
<p>This is the rationale for the Australian Technical Advisory Group on Immunisation’s (ATAGI) September <a href="https://www.health.gov.au/news/atagi-update-on-the-covid-19-vaccination-program">recommendation</a> for people aged 75 or older to get boosted if more than six months had passed since their last vaccine dose. </p>
<p>ATAGI also recommended people aged 65-74, and people 18 years and over with severe immunocompromising conditions, consider having another booster.</p>
<p>But, by the end of October 2023, <a href="https://www.health.gov.au/sites/default/files/2023-10/covid-19-vaccine-rollout-update-27-october-2023.pdf">it was estimated</a> only one-quarter of Australians aged 65-74, one-third of people aged 75 or over and fewer than half (45%) of people in aged care had received a COVID vaccine in the past six months.</p>
<figure class="align-center ">
<img alt="Woman receives vaccination" src="https://images.theconversation.com/files/558309/original/file-20231108-19-5fu6vv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/558309/original/file-20231108-19-5fu6vv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=249&fit=crop&dpr=1 600w, https://images.theconversation.com/files/558309/original/file-20231108-19-5fu6vv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=249&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/558309/original/file-20231108-19-5fu6vv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=249&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/558309/original/file-20231108-19-5fu6vv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=313&fit=crop&dpr=1 754w, https://images.theconversation.com/files/558309/original/file-20231108-19-5fu6vv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=313&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/558309/original/file-20231108-19-5fu6vv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=313&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">People with immunocompromising conditions should get boosted.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/woman-wearing-protective-face-mask-getting-1966499908">Shutterstock</a></span>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/millions-of-australians-still-havent-had-their-covid-boosters-what-message-could-convince-them-now-190482">Millions of Australians still haven't had their COVID boosters. What message could convince them now?</a>
</strong>
</em>
</p>
<hr>
<h2>Which vaccines are available?</h2>
<p>Currently available bivalent vaccines protect against the original ancestral strain of SARS-CoV-2 (now extinct) plus the newer BA.1 or BA.4/5 variants. These bivalent vaccines also protect us against <a href="https://assets.publishing.service.gov.uk/media/6527f0bfaea2d0000d219c69/vaccine-surveillance-report-2023-week-41.pdf">severe disease</a> from the Omicron variants circulating now, such as XBB.</p>
<p>But we can expect newer monovalent XBB.1.5 vaccines soon, now the Therapeutic Goods Administration has <a href="https://www.tga.gov.au/products/covid-19/covid-19-vaccines/covid-19-vaccines-regulatory-status">approved them</a>. These are expected to provide <a href="https://www.medrxiv.org/content/10.1101/2023.10.04.23296545v1.full.pdf">better protection</a> against newer Omicron variants than the currently available <a href="https://www.sciencedirect.com/science/article/pii/S2213260023003065">bivalent vaccines</a>.</p>
<p>In the meantime, boosting with any available COVID vaccine will provide <a href="https://assets.publishing.service.gov.uk/media/6527f0bfaea2d0000d219c69/vaccine-surveillance-report-2023-week-41.pdf">good protection</a> for vulnerable people.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/cdc-greenlights-two-updated-covid-19-vaccines-but-how-will-they-fare-against-the-latest-variants-5-questions-answered-213341">CDC greenlights two updated COVID-19 vaccines, but how will they fare against the latest variants? 5 questions answered</a>
</strong>
</em>
</p>
<hr>
<h2>What might we expect from COVID in 2024?</h2>
<p>The Northern Hemisphere appears to have settled into an approximate seasonal pattern of COVID infections in 2023 and it’s plausible Australia will follow suit. </p>
<p>If so, we should plan for overlapping seasonal epidemics of our three most important respiratory viruses: SARS-CoV-2, influenza and respiratory syncytial virus (RSV). So hospitals may need to plan ahead for larger peaks in admissions.</p>
<p>Hopefully, new <a href="https://www.cdc.gov/vaccines/hcp/acip-recs/vacc-specific/rsv.html">vaccines for RSV</a>, and more broadly protective <a href="https://www.nih.gov/news-events/nih-research-matters/research-context-progress-toward-universal-vaccines">flu and COVID vaccines</a> to be developed over the next decade, should help.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/rsv-is-everywhere-right-now-what-parents-need-to-know-about-respiratory-syncytial-virus-208855">RSV is everywhere right now. What parents need to know about respiratory syncytial virus</a>
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</em>
</p>
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<img src="https://counter.theconversation.com/content/216820/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>James Wood receives funding from NSW Health and the National Health and Medical Research Council for projects on COVID-19. He has previously received funding from the federal government as part of COVID responses in 2020-21 and from WHO Western Pacific Regional Office in 2020. He is a current member of the Australian Technical Advisory Committee on Immunisation.</span></em></p><p class="fine-print"><em><span>Bette Liu receives funding from the Australian National Health and Medical Research Council and Australian Government. </span></em></p><p class="fine-print"><em><span>Katie Flanagan receives funding from the National Health and Medical Research Council, Medical Research Future Fund, Bill and Melinda Gates Foundation and Clifford Craig Foundation. She is involved in research projects studying the impact of COVID-19 vaccine boosters. She is a member of the Australian Technical Advisory Group on Immunisation and President of the Australasian Society for Infectious Diseases.</span></em></p><p class="fine-print"><em><span>Stuart Turville receives funding from the Australian National Health and Medical Research Council, Medical Research Future Fund and Covid grants (Round 2 Covid grant and VIIM vaccine group) awarded from the NSW state government.</span></em></p>This is expected to be the smallest Omicron wave so far. But eligible older and vulnerable people are still recommended to have a booster.James Wood, Professor, epidemiological modelling of infectious diseases, UNSW SydneyBette Liu, Associate Professor and NHMRC Career Development Fellow, UNSW SydneyKatie Louise Flanagan, Infectious Diseases Specialist and Clinical Professor, University of TasmaniaStuart Turville, Associate Professor, Immunovirology and Pathogenesis Program, Kirby Institute, UNSW SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2154112023-10-30T16:14:51Z2023-10-30T16:14:51ZTB vaccine: WHO expert explains why it’s taken 100 years for a scientific breakthrough, and why it’s such a big deal<iframe id="noa-web-audio-player" style="border: none" src="https://embed-player.newsoveraudio.com/v4?key=x84olp&id=https://theconversation.com/tb-vaccine-who-expert-explains-why-its-taken-100-years-for-a-scientific-breakthrough-and-why-its-such-a-big-deal-215411&bgColor=F5F5F5&color=D8352A&playColor=D8352A" width="100%" height="110px"></iframe>
<p><em>The <a href="https://www.cdc.gov/tb/publications/factsheets/prevention/bcg.htm">BCG vaccine for TB</a> has been used for 100 years. It is largely effective for children under five, but less so in older people and can’t be used on patients who have certain medical conditions. Today we’re the closest we’ve ever been to discovering a vaccine that might replace or complement it. Charles Shey Wiysonge, the World Health Organization’s Regional Adviser for Immunisation, discusses the latest developments in the fight against one of the world’s deadliest diseases.</em></p>
<h2>Why has it taken so long?</h2>
<p>We do not yet have a new vaccine for TB. But, for the first time, there are several vaccine candidates that are at <a href="https://www.who.int/teams/global-tuberculosis-programme/research-innovation/vaccines">advanced stages</a> of clinical development. </p>
<p>Vaccine development usually takes decades and unfolds step by step. Experimental vaccine candidates are created in the laboratory and tested in animals before moving into progressively larger human clinical trials. </p>
<p>Clinical trials are research studies that test an intervention such as a vaccine in human beings and occur in phases, from phase 1 to phase 3. We say vaccines are in clinical development when they reach the clinical trial stage. </p>
<ul>
<li><p>A phase 1 trial is a first-in-human study which recruits a small number of healthy people (usually fewer than 100), to assess whether a candidate vaccine is safe. </p></li>
<li><p>Phase 2 trials are typically conducted among several hundred participants, to assess whether the candidate vaccine produces an immune response. </p></li>
<li><p>For phase 3 trials, thousands of people are enrolled to assess whether the vaccine is efficacious and safe. Phase 3 TB vaccine trials are currently going on in Gabon, Kenya, Russia, South Africa, Tanzania and Uganda.</p></li>
</ul>
<p>Even though we are still, at best, three years away from broad regulatory approval of a new TB vaccine, the scientific community can do a lot now to prepare for its use, and to inform the public so that the vaccine may be accepted when it becomes available. </p>
<p>TB vaccines are very challenging to develop. The bacterium that causes the disease is complex, and is proficient at evading the human immune system. We don’t yet have a full understanding of how to appropriately target the bacterium or what kind of immune responses are needed to induce immunity. But there are some interesting approaches in the pipeline and there have been some encouraging data from clinical trials that are providing clues.</p>
<h2>Why do we need a new TB vaccine?</h2>
<p>TB is a global health emergency. About <a href="https://www.who.int/news-room/fact-sheets/detail/tuberculosis">2 billion</a> people are currently infected with <em>Mycobacterium tuberculosis</em>, and of those, <a href="https://www.who.int/health-topics/tuberculosis#tab=tab_1">5% to 10%</a> may become ill with TB and will potentially transmit the bacterium. </p>
<p><a href="https://www.who.int/teams/global-tuberculosis-programme/tb-reports/global-tuberculosis-report-2022">In 2021</a>, nearly 10.6 million people developed TB disease and 1.6 million died. We urgently need new tools to fight TB, including new and improved vaccines.</p>
<p>The <a href="https://www.cdc.gov/tb/publications/factsheets/prevention/bcg.htm">Bacille Calmette-Guérin</a> (BCG) vaccine has saved tens of millions of lives and is effective in children under the age of five in preventing TB deaths and severe forms of the disease. </p>
<p>The vaccine has variable efficacy for protection against <a href="https://medlineplus.gov/ency/article/000077.htm#:%7E:text=Pulmonary%20TB%20is%20caused%20by,infection%20is%20called%20primary%20TB.">pulmonary TB</a> (TB affecting the lungs) in adolescents and adults – and it is pulmonary TB that’s responsible for the majority of TB transmission. So new and improved vaccines that are effective in preventing pulmonary TB in adolescents and adults are essential to control TB, and to reduce transmission to all, including newborn babies.</p>
<p>TB is the leading cause of death among people living with HIV. People living with HIV have up to <a href="https://www.unaids.org/sites/default/files/media_asset/tb-and-hiv_en.pdf">20 times higher</a> risk of developing TB disease compared to those without HIV infection. The current BCG vaccine is not recommended for use in people living with HIV, for safety reasons. Although BCG is a safe vaccine in <a href="https://www.verywellhealth.com/immunocompetent-1069342">immunocompetent</a> infants (those whose immune systems are working properly), severe adverse events can occur in HIV-infected infants following vaccination with BCG.</p>
<p>These adverse events include a rare but life threatening condition known as <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2718164/">disseminated BCG disease</a>. However, new TB vaccine candidates are being developed and evaluated to offer clinical benefit in people living with HIV. </p>
<h2>How effective has the BCG vaccine been?</h2>
<p>BCG vaccines are given to more than <a href="https://pubmed.ncbi.nlm.nih.gov/35961354/">100 million children</a> every year worldwide, at birth or soon after. The effectiveness of BCG can vary depending on several factors, including the prevalence of TB in a given area, the strain of the BCG vaccine used, and the age at which BCG was administered.</p>
<p><a href="https://iris.who.int/bitstream/handle/10665/260306/WER9308.pdf?sequence=1">Several studies</a> have shown that the effect of the BCG wanes as children approach adolescence. People may become infected with TB but not be aware of it. </p>
<h2>What will happen to the BCG vaccine?</h2>
<p>The BCG vaccine will not be replaced by another TB vaccine until and unless there is compelling data on the safety and efficacy of an alternative. Most of the current vaccines in advanced stages of clinical trials are tested in adolescents and adults. Their safety and efficacy would need to be proven in newborn infants to be able to replace BCG. </p>
<p>In addition, BCG vaccination has <a href="https://www.who.int/publications/i/item/who-wer9308-73-96">nonspecific beneficial effects on overall mortality</a> and leads to more reductions in child mortality than would be expected by just protecting against tuberculosis. There is thus a great possibility that BCG would remain in use.</p>
<h2>What will a new vaccine mean for the fight against TB?</h2>
<p>This depends on what the clinical trial data for the new vaccine candidates show. Most importantly, any new vaccine will need to be safe, and it will need to offer clear clinical benefit to populations at risk. We hope that the TB vaccine candidates that are in the pipeline will be effective at reducing TB infection, TB disease and TB transmission and can become part of a combination of tools in the fight against TB.</p>
<p><em>This article is part of a media partnership between The Conversation Africa and the 2023 Conference on Public Health in Africa.</em></p><img src="https://counter.theconversation.com/content/215411/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Charles Shey Wiysonge previously received funding from the South African Medical Research Council.</span></em></p>In 2021 10.6 million people developed TB and 1.6 million died from the disease. Now, for the first time in 100 years, there are promising signs of a vaccine breakthrough.Charles Shey Wiysonge, Regional Adviser, Immunisation, WHO Regional Office for Africa, Stellenbosch UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2119492023-10-30T14:59:17Z2023-10-30T14:59:17ZWhy some people got blood clots after the AstraZeneca vaccine – new clues<p>AstraZeneca in partnership with the University of Oxford developed one of the first vaccines against COVID. The vaccine, which used an adenovirus to smuggle instructions into human cells to make antibodies against the novel coronavirus, saved countless lives. But a problem soon emerged. A tiny proportion – <a href="https://www.nejm.org/doi/10.1056/NEJMoa2109908">about one in 50,000</a> – of those vaccinated developed blood clots. </p>
<p>This blood clot syndrome is known as <a href="https://www.nejm.org/doi/full/10.1056/nejmoa2105385">vaccine-induced immune thrombotic thrombocytopenia</a> (VITT). In people with this condition, something goes wrong with the immune response and people make antibodies that can stick to one of the body’s own proteins.</p>
<p>The protein is called platelet factor 4 (PF4). We know that in the course of infection, many people make antibodies that stick to PF4 as part of the immune response, but these antibodies usually stick weakly. In VITT, antibodies form that can stick to PF4 like superglue.</p>
<p>The antibodies in VITT glue PF4 molecules together, forming large structures known as “immune complexes”. These complexes bind to and activate small cells called platelets that are vital for blood clotting. Normally, platelets float around in the blood in an inactive state, but once activated they spread out, get very sticky, and spew out hundreds of different chemicals.</p>
<p>In VITT, platelets are strongly activated and this causes blood clots. The blood clots commonly affect the veins surrounding the brain, which is a very unusual and rare site for clots. Many people with VITT reported <a href="https://www.nejm.org/doi/full/10.1056/NEJMoa2109908">excruciating headaches</a>, which continue to affect survivors.</p>
<p>Billions of platelets get used up in these clots, leading to low numbers of platelets in the blood. In some patients, this led to serious bleeding and <a href="https://www.nejm.org/doi/full/10.1056/NEJMoa2109908">nearly one in four died</a>. Many survivors are also have <a href="https://bmjopen.bmj.com/content/13/7/e072658">life-long, disabling symptoms</a>.</p>
<h2>Looking for clues</h2>
<p>In just two and a half years, doctors and scientists around the world have begun to unravel the secrets of VITT. How VITT causes clots and why some people get it is a main area of work. Through understanding this, potential treatments are also being discovered.</p>
<p>So far, there is only one genetic clue as to why some people get VITT. A variation of a gene that makes <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9906116/">parts of antibodies</a> is linked to VITT and this is more common in people of European descent – Europeans seem to be at higher risk of VITT. There must be other genes involved, but they are tricky to find. In the UK, scientists have done DNA sequencing on over 200 patients with VITT and results are expected soon.</p>
<p>In our lab, we work on how platelets get activated in VITT. In 2021, our team showed the <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8697531/">main mechanism for platelet activation</a> and have recently <a href="https://ashpublications.org/blood/article/doi/10.1182/blood.2023020872/498431/PF4-activates-the-c-Mpl-Jak2-pathway-in-platelets">discovered another mechanism</a>. In a test tube, we can block this activation with commonly used medicines. </p>
<figure class="align-center ">
<img alt="A digital drawing of a blood clot forming in the body." src="https://images.theconversation.com/files/556594/original/file-20231030-19-f88n2o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/556594/original/file-20231030-19-f88n2o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/556594/original/file-20231030-19-f88n2o.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/556594/original/file-20231030-19-f88n2o.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/556594/original/file-20231030-19-f88n2o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/556594/original/file-20231030-19-f88n2o.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/556594/original/file-20231030-19-f88n2o.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Certain genes are linked to greater risk of VITT.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-illustration/blood-clot-damaged-vessel-made-red-2015637386">Kateryna Kon/ Shutterstock</a></span>
</figcaption>
</figure>
<p>We also see a lot of variation in how platelets from healthy people respond to PF4 and VITT antibodies. We think that this variation in responses is a reason why some people get VITT. We are doing more work to find out the differences between platelets of “high” and “low” responders.</p>
<p>Another major puzzle with VITT is why so many people have clots in the brain. To put this into perspective, spontaneous clots in the brain are very rare. They only affect around <a href="https://www.nejm.org/doi/10.1056/NEJMra042354">three or four people in a million a year</a>, yet over <a href="https://www.nejm.org/doi/full/10.1056/NEJMoa2109908">half of the patients with VITT had these clots</a>.</p>
<p>There are some theories about why clots in the brain happen more in patients with VITT. These include the speed of blood flow, and the stickiness of PF4 and antibodies to the blood vessels. Recently, Canadian scientists showed that patients whose antibodies stick to PF4 the strongest are most likely to get clots <a href="https://linkinghub.elsevier.com/retrieve/pii/S1538-7836(23)00512-3">in the brain</a>.</p>
<h2>Still widely used in low-income countries</h2>
<p>Although adenoviral vaccines have saved millions of lives, they have fallen out of favour in developed countries because of the risk of VITT. However, these vaccines are still widely used in low-income countries. They are highly effective, cheap, and much easier to store and transport than mRNA vaccines – such as the Pfizer-BioNTech and Moderna jabs.</p>
<p>Improving the knowledge of VITT has also prompted scientists to look more closely at other patients with unexplained blood clots. Remarkably, more and more patients with clots, low platelets, and VITT-like antibodies are <a href="https://www.sciencedirect.com/science/article/abs/pii/S1538783623003951?via%3Dihub">being found</a>. These cases are unrelated to vaccination.</p>
<p>Recently, a <a href="https://www.nejm.org/doi/full/10.1056/NEJMc2307721">VITT-like syndrome</a> was reported in two patients after adenovirus infection rather than vaccination. Testing for these antibodies will probably become routine for patients with unexplained blood clots.</p>
<p>Most importantly, imagine a new pandemic that is a lot more dangerous than COVID – perhaps a third of people who catch it die. There would be panic and chaos. We would desperately need adenoviral vaccines despite the risk of VITT. That’s why it’s important to understand VITT inside and out.</p><img src="https://counter.theconversation.com/content/211949/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Richard has received funding from the UK Department of Health and Social Care (DHSC), supported by the National Institute for Health Research (NIHR), and from the British Heart Foundation. Richard is also a named investigator for unrelated research funded by AstraZeneca.</span></em></p><p class="fine-print"><em><span>Samantha Montague receives funding from the UK Department of Health and Social Care (DHSC), supported by the National Institute for Health Research (NIHR), and from the British Heart Foundation.</span></em></p>Adenoviral vaccines are widely used. We need to know why some people get deadly blood clots.Richard Buka, Haematology Registrar and Clinical Research Fellow, University of BirminghamSamantha Montague, Postdoctoral Research Fellow, Institute of Cardiovascular Sciences, University of BirminghamLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2151392023-10-25T11:16:03Z2023-10-25T11:16:03ZCrack vaccine research we did on rats could help babies of mothers who use cocaine – and reduce addiction<p>The most recent <a href="https://inpad.org.br/wp-content/uploads/2014/03/Lenad-II-Relat%C3%B3rio.pdf">statistics</a> put the number of <a href="https://www.unodc.org/res/WDR-2023/annex/1.1_Prevalence_of_drug_use_in_the_general_population_regional_and_global_estimates.xlsx">regular cocaine or crack cocaine users</a> in the world at 20 million. Of these, one in four will become addicted or develop use disorders.</p>
<p>Among the addicts, many are women who, when they become pregnant, can bring risks to themselves and their children. <a href="https://academic.oup.com/epirev/article-abstract/16/2/315/415440?redirectedFrom=fulltext">Cocaine use during pregnancy</a> is associated with serious conditions for pregnant women (such as severe pre-eclampsia or miscarriage) and babies (premature birth with complications, low birth weight, malformations and withdrawal syndrome in the newborn).</p>
<p>A study carried out by a research team I am part of at Universidade Federal de Minas Gerais (UFMG), in Brazil, has achieved a breakthrough: <a href="https://pubs.acs.org/doi/10.1021/acs.jmedchem.3c00366">a vaccine</a> that uses the immune system to prevent the perinatal consequences of drug use, and which could protect the children of drug-using mothers. If clinical studies prove the vaccine’s efficacy, it could be an important tool to complement the biopsychosocial treatments already used to treat people with cocaine and crack addictions.</p>
<p>Pre-clinical tests with the new vaccine on animals have already been carried out successfully. At the moment, the research project is trying to get this experimental drug registered with the Brazilian Health Regulatory Agency <a href="https://www.gov.br/anvisa/pt-br/english">Anvisa</a> so that clinical trials can begin and is looking for funds to carry them out.</p>
<h2>More than a decade in the making</h2>
<p>During <a href="https://www.sciencedirect.com/science/article/pii/S0306453012000522">my doctorate</a>, I studied how our bodies produce antibodies that contribute to the perception of certain symptoms of <a href="https://www.sciencedirect.com/science/article/abs/pii/S0278584610003726">depression</a>. These antibodies, induced by intestinal bacteria, are capable of changing the action of certain hormones and neurotransmitters and changing our perception, creating symptoms and modifying our perception. In 2011, when I applied to UFMG, I started working on the idea of using this knowledge to produce a vaccine against cocaine.</p>
<p>A few years earlier, <a href="https://linkinghub.elsevier.com/retrieve/pii/S0264410X0100425X">an American group had published articles</a> showing that cocaine produced antibodies in some addicts who used very large quantities of the drug. They then began studies with the aim of using this mechanism, which we can call a self-defensive mechanism of the organism, to help people with addictions to cocaine and its derivatives, such as crack.</p>
<p>I was already working on the vaccine when scientific research ran into reality: a tragic situation we experienced in Minas Gerais state became another trigger for the vaccine’s development. In 2013, the Public Prosecutor’s Office issued a rule to the Family Courts, obliging doctors to notify cases of births to drug-dependent women, which would take the newborn children into the adoption system. Immediately, hundreds of women arrived at the drug addiction clinic at UFMG’s Hospital das Clínicas, asking for help so they wouldn’t lose custody of their children.</p>
<p>It was a very sad situation. Motherhood is a time of conflict for these women, who want to protect the baby, but often can’t avoid the compulsion to use the drug. Only <a href="https://link.springer.com/article/10.1007/s11469-018-0005-7">25 per cent</a> of them manage to stop using during pregnancy.</p>
<p>But science is also made up of encounters. When I raised the issue with Professor <a href="http://lattes.cnpq.br/5930812704632756">Ângelo de Fátima</a>, one of Brazil’s leading experts in medicinal chemistry, he offered to replicate the molecule that the Americans had produced so that we could try an experiment on pregnant rats. A while later we talked about a new type of molecule, which had produced an immunogenic response to cancer, and from there came an innovation, a <a href="https://www.sciencedirect.com/science/article/pii/S2090123221001715">totally synthetic molecule</a>, which we now call UFMG-V4N2.</p>
<p>After discussing the possible immunogenicity - the ability to induce an immune response - of molecular structures called calixarenes, we agreed that he would synthesise a new molecule, called UFMG-V4N2, which is the basis of the Calixcoca vaccine. UFMG-V4N2 is actually a vaccine platform that can virtually be used to produce other vaccines, against methamphetamine, opioid and nicotine addiction, for example, for which we already have molecule designs under study.</p>
<h2>Protected pregnancy</h2>
<p>In the <a href="https://pubmed.ncbi.nlm.nih.gov/36822966/">study with the rats</a>, we observed that the vaccination induced the production of antibodies in the pregnant animals, which is a major challenge: pregnancy is a state in which the body’s immune response is lower, so that the baby is not considered a foreign body. The production of antibodies in pregnant women is therefore usually more complicated and, in the case of cocaine users, the drug itself already has an immunosuppressive effect.</p>
<p>Given the presence of the two immunosuppressive effects, we thought it would be very difficult for the mechanism to work. But paradoxically, the antibody production response was almost <a href="https://pubmed.ncbi.nlm.nih.gov/34381172/">a thousand times greater</a> than in the male mice. It’s a paradox for which we don’t yet have an immunological explanation, but it’s a finding that opens up a very interesting window of opportunity if this mechanism is reproduced in humans.</p>
<p>The vaccinated rats did not experience the lack of appetite or hyperactivity induced by cocaine, and had 30 per cent more offspring than the unvaccinated rats, which indicates a reduction in miscarriages, placental abruption and other perinatal complications. The antibodies produced were able to block the passage of the drug through the placenta, protecting the mice. Furthermore, we identified that the antibodies also pass through the milk, so when breastfeeding, the women, even when using the drug, may not cause harm to the babies.</p>
<h2>Addiction</h2>
<p>In addition to the benefits of the vaccine for pregnant women and their children, we believe that Calixcoca could also become an important tool to add to the addiction treatment package, which should also involve psychiatric, psychological and social care support and help from the family.</p>
<p>There are medicines that help with other addictions, such as alcohol or tobacco, but not so far for crack and cocaine, which are the drugs that most stimulate the brain’s reward circuit and, consequently, have a very high addictive power. Only 20 per cent of patients who undergo treatments manage to be drug-free within five years, which is a pretty poor result.</p>
<p>UFMG-V4N2 proved effective in producing antibodies and making them <a href="https://www.sciencedirect.com/science/article/pii/S2666934X23000053">block the passage of cocaine into the brain</a>, which means that the vaccinated animals have a reduced perception of the drug’s effect: a very important advantage in a treatment.</p>
<p>This blockage occurs in the following way: we have a “protective shield” called <a href="https://pubmed.ncbi.nlm.nih.gov/25561720/">the blood-brain barrier</a>, which prevents toxic elements, viruses or bacteria from entering the brain, but because the cocaine molecule is very small, it manages to pass through this barrier. The vaccine stimulates the production of antibodies, which bind to the drug molecules, increasing their weight and size and thus preventing them from getting past the protective shield. The cocaine is retained in the blood, but as it is bound to the antibody, it doesn’t act on the heart or arteries either, which means the risk of overdoses is reduced.</p>
<p>Cocaine and crack cocaine addiction is an extremely important medical, psychological and social problem that still has no definitive solution. Even before human trials begin, around 3,500 people have already contacted us spontaneously, interested in taking part as volunteers in clinical studies. That’s why the results achieved so far are so relevant: there is no treatment approved by regulatory agencies worldwide for this purpose, and Calixcoca could represent hope for thousands of users who want to quit the drug but can’t avoid relapsing. We still have a long way to go to complete the development of this treatment, which could contribute to improving the psychosocial treatments currently used to care for people suffering from cocaine and crack addiction.</p><img src="https://counter.theconversation.com/content/215139/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The research into the development of Calixcoca received funding from the Ministry of Justice - National Drug Policy Secretariat; the Minas Gerais State Research Support Foundation (Fapemig); the Chamber of Deputies; the National Council for Scientific and Technological Development (CNPq); and the Minas Gerais State Health Secretariat.</span></em></p>Calixcoca, which is in the final stages of study, could be a tool in the addiction treatment package.Frederico Garcia, Professor do Departamento de Psiquiatria da Faculdade de Medicina, Universidade Federal de Minas Gerais (UFMG)Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2063892023-10-18T12:32:09Z2023-10-18T12:32:09ZCOVID-19 vaccine mandates have come and mostly gone in the US – an ethicist explains why their messy rollout matters for trust in public health<figure><img src="https://images.theconversation.com/files/553070/original/file-20231010-15-y48qlo.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C2121%2C1412&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Proof of COVID-19 vaccination was once required to access many venues during the pandemic.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/close-up-hand-of-doctor-put-label-covid-19-vaccine-royalty-free-image/1313591390">skaman306/Moment via Getty Images</a></span></figcaption></figure><p>Ending pandemics is a <a href="https://www.scientificamerican.com/article/people-not-science-decide-when-a-pandemic-is-over1/">social decision, not scientific</a>. Governments and organizations rely on <a href="https://www.science.org/content/article/who-ends-pandemic-emergency-covid-19-deaths-fall">social, cultural and political considerations</a> to decide when to officially declare the end of a pandemic. Ideally, leaders try to minimize the social, economic and public health burden of removing emergency restrictions while maximizing potential benefits.</p>
<p>Vaccine policy is a particularly complicated part of pandemic decision-making, involving a variety of other complex and often contradicting interests and considerations. Although COVID-19 vaccines have <a href="https://doi.org/10.26099/whsf-fp90">saved millions of lives</a> in the U.S., vaccine policymaking throughout the pandemic was often <a href="https://dx.doi.org/10.2139/ssrn.3680832">reactive</a> and <a href="https://doi.org/10.1186/s12889-021-12432-x">politicized</a>.</p>
<p>A late November 2022 Kaiser Family Foundation poll found that <a href="https://www.kff.org/coronavirus-covid-19/poll-finding/kff-covid-19-vaccine-monitor-december-2022/">one-third of U.S. parents</a> believed they should be able to decide not to vaccinate their children at all. The World Health Organization and the United Nations Children’s Fund reported that between 2019 and 2021, global childhood vaccination experienced its <a href="https://www.who.int/news/item/15-07-2022-covid-19-pandemic-fuels-largest-continued-backslide-in-vaccinations-in-three-decades">largest drop</a> in the past 30 years.</p>
<p>The Biden administration formally <a href="https://www.whitehouse.gov/briefing-room/statements-releases/2023/05/01/the-biden-administration-will-end-covid-19-vaccination-requirements-for-federal-employees-contractors-international-travelers-head-start-educators-and-cms-certified-facilities/">removed federal COVID-19 vaccination requirements</a> for federal employees and international travelers in May 2023. Soon after, the U.S. government officially <a href="https://www.cdc.gov/coronavirus/2019-ncov/your-health/end-of-phe.html">ended the COVID-19 public health emergency</a>. But COVID-19’s burden on health systems <a href="https://doi.org/10.1001/jamanetworkopen.2022.1760">continues globally</a>.</p>
<p>I am a <a href="https://scholar.google.com/citations?user=wSbI9hUAAAAJ">public health ethicist</a> who has spent most of my academic career thinking about the ethics of vaccine policies. For as long as they’ve been around, vaccines have been a classic case study in <a href="https://academic.oup.com/phe/pages/vaccination-ethics">public health and bioethics</a>. Vaccines highlight the tensions between <a href="https://doi.org/10.1186%2F1742-7622-3-13">personal autonomy and public good</a>, and they show how the decision of an individual can have <a href="https://doi.org/10.1073/pnas.1731324100">populationwide consequences</a>. </p>
<p>COVID-19 is <a href="https://www.unc.edu/discover/covid-19-has-become-endemic/">here to stay</a>. Reflecting on the ethical considerations surrounding the rise – and unfolding fall – of COVID-19 vaccine mandates can help society better prepare for future disease outbreaks and pandemics.</p>
<h2>Ethics of vaccine mandates</h2>
<p>Vaccine mandates are the <a href="https://doi.org/10.1136%2Fbmjgh-2020-004877">most restrictive form</a> of vaccine policy in terms of personal autonomy. Vaccine policies can be <a href="https://doi.org/10.1016/j.vaccine.2018.10.019">conceptualized as a spectrum</a>, ranging from least restrictive, such as passive recommendations like informational advertisements, to most restrictive, such as a vaccine mandate that fines those who refuse to comply. </p>
<p>Each sort of vaccine policy also has different forms. Some recommendations <a href="https://doi.org/10.1016/j.lana.2022.100205">offer incentives</a>, perhaps in the form of a monetary benefit, while others are only a <a href="https://doi.org/10.2105%2FAJPH.2014.302425">verbal recommendation</a>. Some vaccine mandates are mandatory in name only, with <a href="https://www.wsj.com/articles/enforcing-vaccine-mandates-is-messy-business-11630582742">no practical consequences</a>, while others may trigger <a href="https://www.wusf.org/health-news-florida/2022-12-27/thousands-of-workers-were-fired-over-vaccine-mandates-for-some-the-fight-goes-on">termination of employment</a> upon noncompliance. </p>
<p>COVID-19 vaccine mandates took many forms throughout the pandemic, including but not limited to <a href="https://www.commonwealthfund.org/blog/2021/covid-19-vaccine-mandates-and-incentives-under-federal-law">employer mandates</a>, <a href="https://nashp.org/states-address-school-vaccine-mandates-and-mask-mandates/">school mandates</a> and <a href="https://www.kff.org/coronavirus-covid-19/issue-brief/key-questions-about-covid-19-vaccine-passports-and-the-u-s/">vaccination certificates</a> – often referred to as <a href="https://www.nytimes.com/2021/02/04/travel/coronavirus-vaccine-passports.html">vaccine passports</a> or <a href="https://doi.org/10.1016/S1473-3099(20)30766-0">immunity passports</a> – required for travel and participation in public life.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/553072/original/file-20231010-21-irjnph.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Sign on window reading 'New York City requires you to be vaccinated against COVID-19 to enter this business,' with a person sitting at a desk inside the room" src="https://images.theconversation.com/files/553072/original/file-20231010-21-irjnph.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/553072/original/file-20231010-21-irjnph.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/553072/original/file-20231010-21-irjnph.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/553072/original/file-20231010-21-irjnph.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/553072/original/file-20231010-21-irjnph.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/553072/original/file-20231010-21-irjnph.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/553072/original/file-20231010-21-irjnph.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">COVID-19 vaccine requirements were intended to protect the health and safety of the public.</span>
<span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/VirusOutbreak/409216582fb54b8f9f74c207206f789e">Seth Wenig/AP Photo</a></span>
</figcaption>
</figure>
<p>Because of ethical considerations, vaccine mandates are typically <a href="https://doi.org/10.1111/bioe.13141">not the first option</a> policymakers use to maximize vaccine uptake. Vaccine mandates are <a href="https://doi.org/10.1016/j.vaccine.2018.10.019">paternalistic by nature</a> because they limit freedom of choice and bodily autonomy. Additionally, because some people may see vaccine mandates as invasive, they could potentially create challenges in maintaining and garnering trust in public health. This is why mandates are usually the last resort. </p>
<p>However, vaccine mandates <a href="https://doi.org/10.1111/bioe.13141">can be justified</a> from a public health perspective on multiple grounds. They’re a <a href="https://doi.org/10.1016%2FS0140-6736(22)00875-3">powerful and effective</a> public health intervention. </p>
<p>Mandates can provide <a href="https://doi.org/10.1016/S0140-6736(22)00875-3">lasting protection</a> against infectious diseases in various communities, including schools and health care settings. They can provide a public good by ensuring widespread vaccination to reduce the chance of outbreaks and disease transmission overall. Subsequently, an increase in community vaccine uptake due to mandates can protect immunocompromised and vulnerable people who are at higher risk of infection.</p>
<h2>COVID-19 vaccine mandates</h2>
<p>Early in the pandemic, <a href="https://www.brookings.edu/articles/vaccine-mandates-are-more-popular-than-you-think/">arguments in favor</a> of mandating COVID-19 vaccines for adults rested primarily on evidence that COVID-19 vaccination prevented disease transmission. In 2020 and 2021, COVID-19 vaccines seemed to have a <a href="https://doi.org/10.1093%2Fcid%2Fciab079">strong effect on reducing transmission</a>, therefore justifying vaccine mandates. </p>
<p>COVID-19 also <a href="https://doi.org/10.1007%2Fs40615-021-01170-w">posed a disproportionate threat</a> to vulnerable people, including the immunocompromised, older adults, people with chronic conditions and poorer communities. As a result, these groups would have <a href="https://doi.org/10.1371%2Fjournal.pmed.1004086">significantly benefited</a> from a reduction in COVID-19 outbreaks and hospitalization.</p>
<p>Many researchers found <a href="https://doi.org/10.1377/forefront.20211029.682797">personal liberty and religious objections insufficient</a> to prevent mandating COVID-19 vaccines. Additionally, decision-makers in favor of mandates appealed to the COVID-19 vaccine’s ability to <a href="https://pubmed.ncbi.nlm.nih.gov/34924609">reduce disease severity and therefore hospitalization rates</a>, alleviating the pressure on overwhelmed health care facilities. </p>
<p>However, the emergence of <a href="https://theconversation.com/what-is-the-new-covid-19-variant-ba-2-and-will-it-cause-another-wave-of-infections-in-the-us-179619">even more transmissible variants</a> of the virus dramatically changed the decision-making landscape surrounding COVID-19 vaccine mandates.</p>
<p>The public health intention (and ethicality) of original COVID-19 vaccine mandates became less relevant as the scientific community understood that achieving herd immunity against COVID-19 was <a href="https://doi.org/10.1038/d41586-021-00728-2">probably impossible</a> because of uneven vaccine uptake, and <a href="https://doi.org/10.1038/d41586-022-00283-4">breakthrough infections</a> among the vaccinated became more common. Many countries like <a href="https://doi.org/10.1136/bmj.o353">England</a> and <a href="https://www.venable.com/insights/publications/2022/02/as-the-federal-vaccine-mandates-fall-one-by-one">various states in the U.S.</a> started to roll back COVID-19 vaccine mandates.</p>
<p>With the rollback and removal of vaccine mandates, decision-makers are still left with important policy questions: Should vaccine mandates be dismissed, or is there still sufficient ethical and scientific justification to keep them in place?</p>
<p>Vaccines are lifesaving medicines that can help everyone eligible to receive them. But vaccine mandates are context-dependent tools that require considering the time, place and population they are deployed in. </p>
<p>Though COVID-19 vaccine mandates are less of a publicly pressing issue today, many other vaccine mandates, <a href="https://www.nytimes.com/2022/12/16/health/vaccines-public-opinion.html">particularly in schools</a>, are currently being challenged. I believe this is a reflection of decreased trust in public health authorities, institutions and researchers – resulting in part from <a href="https://theconversation.com/18-months-of-the-covid-19-pandemic-a-retrospective-in-7-charts-166881">tumultuous decision-making</a> during the COVID-19 pandemic.</p>
<p>Engaging in transparent and honest conversations surrounding vaccine mandates and other health policies can help rebuild and foster trust in public health institutions and interventions.</p><img src="https://counter.theconversation.com/content/206389/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Rachel Gur-Arie does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Vaccine policies fall on a spectrum, from mandates to recommendations. Deciding what to use and when is not so much a science but a balancing act between personal autonomy and public good.Rachel Gur-Arie, Assistant Professor of Nursing and Health Innovation, Arizona State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2147982023-10-03T19:50:49Z2023-10-03T19:50:49Z‘We could eradicate malaria by 2040’ says expert after revolutionary vaccine is approved by WHO<p><em>The World Health Organization has <a href="https://www.who.int/news/item/02-10-2023-who-recommends-r21-matrix-m-vaccine-for-malaria-prevention-in-updated-advice-on-immunization">approved</a> a new vaccine that scientists argue will be a game-changer in the fight against malaria, which kills half a million people in Africa every year. Trials have shown that the <a href="https://www.ox.ac.uk/news/2023-10-02-oxford-r21matrix-m-malaria-vaccine-receives-world-health-organization-recommendation">R21/Matrix vaccine</a>, developed by Oxford University together with the Serum Institute of India, reduces malaria by up to 75%. It can be manufactured cheaply and on a mass scale. The Conversation Weekly spoke to chief investigator Adrian Hill, who is also director of the Jenner Institute at the University of Oxford, about this revolutionary vaccine. Below are edited excerpts from the <a href="https://theconversation.com/the-long-road-to-a-new-malaria-vaccine-told-by-the-scientists-behind-the-breakthrough-podcast-214885">podcast</a>.</em></p>
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<h2>Why is the R21/Matrix vaccine a game-changer?</h2>
<p>We’re seeing about 75% efficacy by counting the reduction in numbers of malaria episodes over a year. The best vaccine prior to this was about 50% over a year, and lower than that over three years.</p>
<p>This is a material improvement, but that’s not the main improvement. The big difference is how you can manufacture it at a scale that is really needed to protect most of the children who need a malaria vaccine in Africa. </p>
<p>There are about 40 million children born every year in malaria areas in Africa who would benefit from a vaccine. Ours is a four-dose vaccine over 14 months, so you need about 160 million doses. We can achieve that. </p>
<p>The Serum Institute of India, our manufacturing and commercial partner, can produce hundreds of millions of doses of this vaccine each year, whereas the previous vaccine could be manufactured at a scale of six million doses a year from 2023 to 2026, according to Unicef reports. </p>
<p>The third real advantage of this vaccine is its cost. We were well aware that we couldn’t produce a US$100 vaccine. It wouldn’t fly for international agencies supporting the purchase and distribution of the vaccine in very low-income countries.</p>
<p>So where we are now is a price that’ll vary according to the scale, but at high volume it should be US$5 a dose.</p>
<h2>Why has developing a malaria vaccine been so difficult?</h2>
<p>People have been trying to make malaria vaccines for over 100 years. Well over 100 vaccines have gone into clinical trials in people. Very, very few have worked to any degree.</p>
<p>Malaria is not a virus, it’s not a bacterium. It’s a protozoan parasite, some thousands of times larger than a typical virus. A good measure of that is how many genes it has. Covid has 13, malaria has about 5,500. This is one of the reasons that malaria is super complex.</p>
<p>There are different parasite forms the first of which are injected by the mosquito into the skin and rapidly go to the liver. They spend a week multiplying there, and then they go into the bloodstream. And they are hugely different during these different stages. And the parasites grow at a rate of tenfold every 48 hours, multiplying furiously. </p>
<p>By the time they get to a really high parasite density, you will be very unwell. Or if you’re unlucky, you will die, typically from cerebral symptoms, a coma or from being severely anaemic. The parasites break open the red blood cells.</p>
<p>And then there’s yet another stage where the parasite changes again to a form that the mosquito can take up through its next bite and continue the life cycle by infecting somebody else.</p>
<p>So this is as complex as it gets with infectious pathogens.</p>
<p>Malaria typically goes through four life cycles and they’re all different. If you can get a really good vaccine for one of those, you will break the cycle of transmission. And that’s what we’ve been trying to do.</p>
<p>We’ve been working on targeting the so-called sporozoites, which is the form that the mosquito inoculates into your skin. We’re trying to trap it before it can get to the liver and carry on the life cycle.</p>
<p>Luckily, there are no symptoms of malaria at that stage. It’s a silent infection until it gets into the blood and starts multiplying inside your red blood cells. </p>
<p>So the sporozoite is a natural target to try and kill the parasite before it multiplies very quickly.</p>
<h2>Tell us about past attempts to develop a malaria vaccine</h2>
<p>Very early on people tried to use the whole microbe in the same way that vaccine pioneer Edward Jenner used the whole virus to inoculate against smallpox. Then the French microbiologist Louis Pasteur came along with bacterial vaccines, and so on.
In about 1943, there was a trial of the whole malaria parasite vaccine candidate in New York with zero efficacy. That put people off for a while.</p>
<p>It wasn’t until the 1980s when we could actually begin to sequence the genes in the parasite that new vaccination candidates appeared. And then within 10 years we had 5,000 candidates because everyone hoped that the gene they had sequenced might be a malaria vaccine. And of course almost all of those failed.</p>
<h2>Why aren’t vaccines for whole parasites effective against malaria?</h2>
<p>It’s the same reason that just getting infected once by malaria doesn’t give you protection against the next infection. </p>
<p>In the areas of malaria where we test our vaccines in Africa, some children get up to eight episodes in three or four months. They get quite unwell with the first and three weeks later they’re having a second bout and so on. Natural immunity doesn’t work until you’ve had a lot of different infections and that’s why adults are generally protected against malaria and don’t become very unwell. </p>
<p>The people who die of malaria in an endemic area are the <a href="https://www.who.int/news-room/fact-sheets/detail/malaria">young children </a> who may never have been infected before and die with their first infection when they’re one year old, or they might have had one or two episodes, but that wasn’t enough to give them sterilising immunity.</p>
<p>Malaria has been around for tens of millions of years. Not just in humans, but in the species that we were before we became humans.</p>
<p>It’s a very wily parasite and has developed <a href="https://academic.oup.com/femsre/article/40/2/208/2570118">immune escape mechanisms </a> of all sorts.</p>
<p>When you try to vaccinate, you suddenly find there’s some way the parasite gets around that, and it’s only when you get up to really extraordinarily high levels of antibodies that the parasite hasn’t seen before and hasn’t learnt to evolve against that it becomes effective.</p>
<h2>Will we ever eradicate malaria entirely?</h2>
<p>Malaria is very high on the list of diseases we want to eradicate. I don’t think it’s going to happen in five years or 10 years, but it should happen in something like 15 years. So 2040 would be a reasonable target. </p>
<p>Nobody’s suggesting we stop doing what we’re doing at the moment with bed nets and spraying and drugs. But now we have a new tool that may be individually more protective than any of the tools we’re using at the moment.</p><img src="https://counter.theconversation.com/content/214798/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Adrian Hill receives funding from government and charitable funders of malaria vaccine development. He has received funding awarded to the University of Oxford from the Serum Institute of India to support clinical trials of the R21/Matrix-M vaccine. He may benefit for a share of any royalty stream to Oxford University from the vaccine.</span></em></p>People have been trying to make malaria vaccines for over 100 years. With the help of the revolutionary new R21/Matrix vaccine the disease could be eradicated by 2040.Adrian Hill, Director of the Jenner Institute, University of OxfordLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2147632023-10-02T15:57:01Z2023-10-02T15:57:01ZNobel prize in medicine awarded to mRNA pioneers – here’s how their discovery was integral to COVID vaccine development<p>Billions of people around the world have received the Pfizer or Moderna COVID-19 vaccines. The rapid development of these vaccines changed the course of the pandemic, providing protection against the SARS-CoV-2 virus. </p>
<p>But these vaccines would not have been possible it if weren’t for the pioneering work of <a href="https://www.nobelprize.org/prizes/medicine/2023/press-release/">this year’s winners</a> of the Nobel prize in physiology or medicine decades earlier.</p>
<p>Dr Katalin Karikó and Dr Drew Weissman, researchers from the University of Pennsylvania, have been given the prestigious award for their discoveries into mRNA biology. The pair were the first to discover a way of modifying mRNA that allowed it to successfully be delivered to cells and replicated by them. </p>
<p>Their discovery was not only integral to COVID-19 vaccine development, but may also lead to the development of many other therapies – such as vaccines for cancer.</p>
<h2>Life’s work</h2>
<p>Karikó is a Hungarian biochemist and Weissman an American physician scientist. The two began working together in 1985 when Karikó was a postdoctoral researcher at the University of Pennsylvania, where Weissman was already working as an immunologist. They had a shared interest in how mRNA could be used to make new therapies. </p>
<p>Messenger RNA (better known as mRNA) is an essential molecule to life. It’s made in the body from our very own DNA in a process called translation. DNA is our special encoded handbook of instructions for manufacturing proteins, which are the building blocks for material in the body. </p>
<p>Our mRNA copies and carries these genetic instructions from our DNA to our cells. The cells then make whatever protein they’ve been instructed to, such as haemoglobin which helps red blood cells carry oxygen around the body.</p>
<p>Karikó and Weissman thought that if it was possible to commandeer this process, mRNA could be used to instruct cells to essentially make their own cures. But at the time they started working together, attempts by other researchers to do this had been unsuccessful.</p>
<p>The researchers faced two major challenges as they began their work. The first was being able to prevent the host from mounting an immune response against the modified mRNA. The second was being able to deliver the mRNA into the host safely without it degrading.</p>
<p>To understand how they overcame the first barrier, it’s important to understand mRNA’s structure. Normally, mRNA molecules contain four types of smaller molecules known as bases (nucleosides): A (adenine), U (uridine), G (guanine), and C (cytosine). Different sequences of these bases can be strung together to produce the basis of an mRNA molecule.</p>
<figure class="align-center ">
<img alt="A digital illustration of a strand of mRNA." src="https://images.theconversation.com/files/551466/original/file-20231002-19-lxrhms.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/551466/original/file-20231002-19-lxrhms.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/551466/original/file-20231002-19-lxrhms.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/551466/original/file-20231002-19-lxrhms.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/551466/original/file-20231002-19-lxrhms.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/551466/original/file-20231002-19-lxrhms.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/551466/original/file-20231002-19-lxrhms.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Messenger RNA copies and carries genetic instructions from our DNA.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-illustration/molecular-model-messenger-ribonucleic-acid-mrna-2205462601">Kateryna Kon/ Shutterstock</a></span>
</figcaption>
</figure>
<p>In early experiments, Karikó and Weismann found that injecting normal mRNA molecules into mice led to an immune response. This meant the mouse’s immune system saw the new mRNA as an invading pathogen and the immune cells would destroy it, instead of replicating it.</p>
<p>So the <a href="https://www.nature.com/articles/s41577-021-00608-w">researchers modified</a> the U nucleoside to create a pseudouridine, a chemical compound which stabilises RNA’s structure. When they repeated their experiment with the modified mRNA, the mice exhibited <a href="https://www.cell.com/immunity/fulltext/S1074-7613(05)00211-6?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS1074761305002116%3Fshowall%3Dtrue">no immune response</a>.</p>
<p>But Karikó and Weismann still faced the second challenge of being able to deliver the bespoke mRNA without it degrading. </p>
<p>They decided to use lipids (a nanoparticle) to deliver it. These fatty chemical compounds are an essential part of the cell membrane, controlling what enters and leaves the cell. Specially created lipids allowed the mRNA molecules <a href="https://www.cell.com/molecular-therapy-family/molecular-therapy/fulltext/S1525-0016(16)32681-8?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS1525001616326818%3Fshowall%3Dtrue">to be delivered</a> without being degraded or broken down by the immune system. </p>
<p>Karikó and Weissman’s research had successfully eliminated the obstacles that had previously stood in the way of using mRNA clinically. Being able to instruct the body to replicate virtually any harmless protein could have potential for treating a range of diseases and even protect against viral infections.</p>
<h2>COVID vaccines</h2>
<p>When their research was first published, it didn’t garner <a href="https://www.nytimes.com/2023/10/02/health/nobel-prize-medicine.html#:%7E:text=Katalin%20Karik%C3%B3%20and%20Drew%20Weissman%2C%20who%20together%20identified%20a%20chemical,Physiology%20or%20Medicine%20on%20Monday.">much attention</a>. But in 2011, two biotech companies – Moderna and BioNTech – took notice and began research into mRNA medicines.</p>
<p>It’s no wonder why. Traditional vaccine production methods are time consuming, expensive and don’t work for every vaccine. But Karikó and Weissman’s work showed that synthetic mRNA could be made at a large scale. </p>
<p>Researchers had already been working on developing mRNA vaccines before the pandemic, such as a <a href="https://www.nature.com/articles/d41586-022-03590-y#:%7E:text=There%20is%20some%20research%20suggesting,immune%20responses%20in%20guinea%20pigs.">vaccine for Ebola</a> that didn’t receive much commercial interest. But in 2020, when COVID-19 began spreading around the globe, vaccines were needed quickly to offer protection.</p>
<p>Using the foundational work of Karikó and Weissman, scientists developed a bespoke mRNA sequence which mimicked the spike protein (which allows the virus to enter our cells). This produced a harmless COVID particle which our cells then replicated, allowing our bodies to protect us from severe COVID infections when it encountered the real virus.</p>
<p>Karikó and Weissman’s discoveries years earlier were critical in making the COVID-19 mRNA vaccines possible. But these aren’t the only ways their work could be applied. </p>
<p>Researchers are now hoping to develop mRNA vaccines for diseases such as HIV and Zika virus. Studies have also shown mRNA vaccines might be useful in treating <a href="https://theconversation.com/pancreatic-cancer-a-personalised-mrna-vaccine-may-boost-effects-of-treatment-205606">certain types of cancer</a>.</p><img src="https://counter.theconversation.com/content/214763/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Alice Godden does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>The prestigious prize was awarded to Dr Katalin Karikó and Dr Drew Weissman from the University of Pennsylvania.Alice Godden, Senior research associate, School of Biological Sciences, University of East AngliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2085382023-09-21T21:27:36Z2023-09-21T21:27:36ZLyme disease: The pathogen’s cunning strategies for persistent infection offer clues for vaccine development<figure><img src="https://images.theconversation.com/files/547386/original/file-20230911-25-n5os9t.JPG?ixlib=rb-1.1.0&rect=65%2C23%2C1709%2C1158&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The black-legged tick is the vector that spreads Lyme disease. Its bite can infect humans with the Borrelia burgdorferi bacterium.</span> <span class="attribution"><span class="source">(Jim Gathany/CDC)</span></span></figcaption></figure><iframe style="width: 100%; height: 100px; border: none; position: relative; z-index: 1;" allowtransparency="" allow="clipboard-read; clipboard-write" src="https://narrations.ad-auris.com/widget/the-conversation-canada/lyme-disease-the-pathogens-cunning-strategies-for-persistent-infection-offer-clues-for-vaccine-development" width="100%" height="400"></iframe>
<p>Lyme disease is the leading <a href="https://www.who.int/news-room/fact-sheets/detail/vector-borne-diseases">vector-borne disease</a> — meaning diseases that are transmitted to humans from another organism like a tick or mosquito — in <a href="https://doi.org/10.1186/s12889-019-7069-6">North America and Europe</a>. </p>
<p><a href="https://doi.org/10.3201/eid2702.202731">New human cases are estimated</a> at over <a href="http://dx.doi.org/10.15585/mmwr.ss6622a1">400,000 in the United States each year</a>. Canada has experienced a drastic increase in human cases, <a href="https://www.canada.ca/en/public-health/services/diseases/lyme-disease/surveillance-lyme-disease.html#a5">from 266 cases in 2011 to 3,147 in 2021</a>, as the habitat of its vector, a tick, expands north. </p>
<p>The initial symptoms of human Lyme disease can be vague, such as fever, headache, fatigue and often rash. It is a potentially serious condition that can affect multiple systems in the body — including the heart, nervous system and joints — and can become a chronic illness.</p>
<p>Lyme disease is caused by a unique, spiral-shaped (spirochete) bacterium called <a href="https://doi.org/10.1099/00207713-34-4-496"><em>Borrelia burgdorferi</em></a>. <em>B. burgdorferi</em> cannot survive in the environment on its own. For <a href="https://doi.org/10.21775/cimb.042.473">survival and transmission</a>, it requires susceptible hosts (usually small mammals or birds) and a <a href="https://doi.org/10.1056/NEJM198303313081301">specific vector</a>: the black-legged tick, also called the deer tick.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/535388/original/file-20230703-257464-m0lz6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/535388/original/file-20230703-257464-m0lz6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=420&fit=crop&dpr=1 600w, https://images.theconversation.com/files/535388/original/file-20230703-257464-m0lz6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=420&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/535388/original/file-20230703-257464-m0lz6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=420&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/535388/original/file-20230703-257464-m0lz6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=528&fit=crop&dpr=1 754w, https://images.theconversation.com/files/535388/original/file-20230703-257464-m0lz6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=528&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/535388/original/file-20230703-257464-m0lz6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=528&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Lyme disease infectious cycle: Adult ticks lay egg sacs that can hatch thousands of tick larvae. Larvae are not born with Borrelia burgdorferi but can acquire the bacterium when they feed on an infected host. After feeding, larvae molt to nymphs which must feed once to molt to adults. Female adult ticks also feed once before laying the egg sac. Nymphs and adult ticks can transmit B. burgdorferi to susceptible hosts while feeding.</span>
<span class="attribution"><span class="source">(BioRender)</span></span>
</figcaption>
</figure>
<h2>Evading the immune system</h2>
<p><em>B. burgdorferi</em> must survive extremely diverse conditions over the course of its transmission and infection cycle: from host to tick vector, and then into new hosts. </p>
<p>This bacterium senses and responds to its surroundings, most notably by <a href="https://doi.org/10.1128/iai.70.7.3382-3388.2002">modifying its appearance</a> by changing the <a href="https://doi.org/10.1073/pnas.92.7.2909" title="). _B. burgdorferi_ has over [50 surface-exposed proteins](https://doi.org/10.1128/jb.00658-16 "">proteins on its outer surface</a> to <a href="https://doi.org/10.1111/j.1574-695X.2012.00980.x">help it survive</a> in either <a href="https://doi.org/10.1038/s41467-023-35897-3">the tick</a> or the host.</p>
<p>When a tick infected by <em>B. burgdorferi</em> bites and feeds on a vertebrate host, it provides a signal for the bacteria to switch its proteins to those required to infect the host, and to begin migrating through the tick and into the bite site. This process takes between <a href="https://doi.org/10.4269/ajtmh.1995.53.397">36 and 72 hours</a>. </p>
<p>However, many of these proteins are recognized by the host as foreign, and the host’s immune system works to try to clear the infection. This includes a strong, antibody response targeted against <em>B. burgdorferi</em>. </p>
<p>Despite these immune responses, <em>B. burgdorferi</em> is able to cause long-term infections. In natural host reservoirs — the animals that the bacterium usually finds itself in via tick bites, such as small rodents — these infections do not cause diseases like those seen in humans and other <a href="https://doi.org/10.1016/j.idc.2007.12.013">non-natural reservoirs</a>. </p>
<p>In fact, the bacteria itself does not produce any products that would be <a href="https://doi.org/10.1016/j.cll.2015.07.004">toxic to its hosts</a>, either natural or non-natural. Yet chronic infection in humans can lead to <a href="https://doi.org/10.1038/nrdp.2016.90">Lyme neuroborreliosis, carditis and Lyme arthritis</a>.</p>
<figure class="align-center ">
<img alt="Bacteria that look like bright green and yellow squiggles against a dark green background" src="https://images.theconversation.com/files/548570/original/file-20230915-23-4ysjok.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/548570/original/file-20230915-23-4ysjok.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=612&fit=crop&dpr=1 600w, https://images.theconversation.com/files/548570/original/file-20230915-23-4ysjok.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=612&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/548570/original/file-20230915-23-4ysjok.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=612&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/548570/original/file-20230915-23-4ysjok.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=770&fit=crop&dpr=1 754w, https://images.theconversation.com/files/548570/original/file-20230915-23-4ysjok.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=770&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/548570/original/file-20230915-23-4ysjok.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=770&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Microscopic image of Lyme disease bacteria Borrelia burgdorferi. In this photo, immunofluorescent antibodies have been used to change the colour of spirochetes that express different outer surface proteins.</span>
<span class="attribution"><span class="source">(NIAID)</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>How then, are these bacteria able to cause such a devastating disease in humans and other animals, but not in their natural host reservoirs?</p>
<p>While there is still much to learn about <em>B. burgdorferi</em>, we know of several factors that play a role in the <a href="https://doi.org/10.1038/nrdp.2016.90">range of disease it causes</a>. These include:</p>
<ul>
<li>its genetic make-up, </li>
<li>its ability to access various tissues (such as the joints, heart and nervous system) due to its <a href="https://doi.org/10.1128/iai.01228-12">ability to move around (motility)</a>, and </li>
<li>the immune response of the host. </li>
</ul>
<p>Apart from motility, <em>B. burgdorferi</em> also protects itself from the strong <em>B. burgdorferi</em>-specific targeted antibody response of its host’s immune system by changing the appearance of the main outer surface protein expressed during persistent infection in a process called <a href="https://doi.org/10.1128/iai.66.8.3698-3704.1998">antigenic variation</a>.</p>
<h2>How Lyme disease is perpetuated</h2>
<p>In addition to antigenic variation, <em>B. burgdorferi</em> bacteria can also change their DNA by <a href="https://doi.org/10.1073/pnas.0402745101">exchanging genetic information, a process also known as gene transfer</a>. This process allows these bacteria to further alter their <a href="https://doi.org/10.1128/mbio.00153-10">appearance</a> <a href="https://doi.org/10.1534/genetics.111.130773">during infection</a> to avoid the host immune system.</p>
<p>This process works so well that these <em>B. burgdorferi</em> bacteria appear different enough to allow <a href="https://doi.org/10.7326/0003-4819-127-2-199707150-00006">re-infection</a> or even <a href="https://doi.org/10.1128/iai.01817-14">co-infection</a> (where multiple strains of B. burgdorferi infect a single host at the same time) of a vertebrate host, like a mouse or a human, despite the presence of specific antibodies to fight the bacterium.</p>
<p>In fact, in nature, the majority of host reservoirs and the ticks that carry the bacterium are infected with <a href="https://doi.org/10.1128/AEM.02296-15">multiple strains of <em>B. burgdorferi</em></a>. The ability of <em>B. burgdorferi</em> to reinfect and co-infect both ticks and hosts increases the spread of the bacteria in the environment as well as the chances that humans will encounter Lyme disease.</p>
<h2>Human cases of Lyme disease are increasing</h2>
<p>As a vector-borne pathogen, <em>B. burgdorferi</em> only infects individuals that are bitten by an infected tick. It is not transmitted from <a href="https://doi.org/10.1093/cid/ciz872">person to person</a>.</p>
<p>Environments that support black-legged/deer ticks are at risk of harbouring <em>B. burgdorferi</em>. In North America, these species of ticks are widely distributed throughout the eastern and midwestern United States. Recent <a href="https://doi.org/10.1093/jme/tjy104">geographic expansion</a> to the north is increasing the prevalence of Lyme disease <a href="https://doi.org/10.1503/cmaj.080148">in Canada</a>. </p>
<p>The increase of human Lyme disease cases highlights the failure of existing preventive strategies — such as minimizing exposure to tick habitats, performing diligent tick checks, and wearing suitable clothing when performing activities in known tick habitats — and emphasizes the need for an effective <a href="https://doi.org/10.21775/cimb.042.191">human vaccine</a>.</p>
<h2>A One Health approach</h2>
<p>At <a href="https://www.vido.org/">Vaccine and Infectious Disease Organization</a> at the University of Saskatchewan, we are taking a <a href="https://ipac-canada.org/one-health">One Health</a> approach by recognizing that human health is closely related to the health of animals and the shared environment. We are investigating the role of <em>B. burgdorferi</em>, ticks, and susceptible animals on the spread and survival of the Lyme disease bacterium. </p>
<p>It is important to mimic the natural infectious cycle as much as possible when identifying potential vaccine and drug targets. This is because the way host animals are infected (for example, artificial needle infection or natural tick bite) can produce drastic differences in the resulting infection. </p>
<p>Additionally, despite the prevalence of this disease, there are still many aspects of the infectious cycle that remain unknown due to the uniqueness of <em>B. burgdorferi</em> and a lack of knowledge about the tick vector. </p>
<p>For example, we recently learned that a <em>B. burgdorferi</em> protein is responsible for regulating the components necessary for the bacterium to infect vertebrates, including humans. The absence of this protein, among other things, leads to the <a href="https://doi.org/10.1038/s41467-023-35897-3">death of <em>B. burgdorferi</em> in ticks</a>, making it an exciting target for research investigation. </p>
<p>By learning more about the molecular mechanisms that change or reduce the severity of the disease caused by this bacterium, we can identify new targets for the prevention of human Lyme disease.</p><img src="https://counter.theconversation.com/content/208538/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jenny Wachter does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>The bacterium that causes Lyme disease is a master of disguise, changing its appearance to evade the immune system as it moves from the ticks that carry it to humans or animals.Jenny Wachter, Research scientist/Adjunct professor, University of SaskatchewanLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2116102023-09-14T02:49:04Z2023-09-14T02:49:04ZKoalas need their booster shots too. Here’s a way to beat chlamydia with just 1 capture and less trauma<p>Chlamydia is a major threat to koala populations across Australia. This bacterial disease infects between 20% and 90% of individuals in koala populations. It’s a <a href="https://www.nature.com/articles/srep42587">major cause</a> of the rapid decline of many wild populations, particularly in South-East Queensland and northern New South Wales. </p>
<p>Our group at Queensland University of Technology (QUT) has developed two vaccines to target chlamydial infections. One of these vaccines, now being trialled in collaboration with Dr Michael Pyne and his staff at Currumbin Wildlife Hospital, has recently had some <a href="https://currumbinsanctuary.com.au/wildlife-hospital/koala-chlamydia-vaccine-research-trial">outstanding results</a> in a wild koala population on the Gold Coast. This population had been declining rapidly due to high rates of the disease. </p>
<p>Two years into the five-year trial, we have seen more than 25 joeys born to vaccinated females. The program involved vaccinating, collaring and releasing 10-20% of young animals each year. All joeys and mums were chlamydia-free. In addition, 11 out of 13 young males vaccinated remain negative at 12–24 months after vaccination. </p>
<p>Like most vaccines, however, this vaccine requires two shots, 30 days apart. This means wild animals must be held in captivity for a month, which many don’t like, or released and recaptured for the booster dose. This is both expensive and <a href="https://theconversation.com/testing-the-stress-levels-of-rescued-koalas-allows-us-to-tweak-their-care-so-more-survive-in-the-wild-196224">traumatic</a> for the animals. </p>
<p>It was during a chat over coffee a few years ago that we first pondered the question, “Could we develop a delayed-release vaccine implant that is given at the same time as the first vaccine and releases the booster vaccine dose 30 days later?”</p>
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Read more:
<a href="https://theconversation.com/testing-the-stress-levels-of-rescued-koalas-allows-us-to-tweak-their-care-so-more-survive-in-the-wild-196224">Testing the stress levels of rescued koalas allows us to tweak their care so more survive in the wild</a>
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<h2>Why vaccination is the best approach</h2>
<p>Chlamydia is spread by <a href="https://www.livescience.com/62517-how-koalas-get-chlamydia.html">direct physical contact</a> between koalas. Symptoms include blindness, urinary tract infections (wet bottom), infertility in females and sperm damage in males. </p>
<p>While antibiotics can be used to treat the eye disease, they cannot be used to treat infertility. This is because antibiotics can destroy the gut bacteria essential for koalas to digest their food, eucalypt leaves. </p>
<p>The vaccine is the best option and is also <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6955670/">very safe</a>. We detected no adverse side-effects across multiple studies. The only complication is the need for a booster shot.</p>
<p>So are implants a solution? Our recent <a href="https://academic.oup.com/biolreprod/article/108/5/758/7044671">research</a> suggests the answer is yes, at least in a sheep model. We have now received a grant from the federal <a href="https://www.dcceew.gov.au/environment/biodiversity/threatened/species/koalas/saving-koalas-fund">Saving Koalas Fund</a> to develop this implant technology for a koala vaccine against the <em>Chlamydia</em> bacterium. </p>
<p>In our sheep trial of a first-generation implant, animals that received the primary vaccination by injection plus a booster implant developed immune T cell numbers equivalent to animals receiving two vaccinations by injection, together with slightly reduced antibody levels. </p>
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<a href="https://images.theconversation.com/files/547927/original/file-20230913-21-o53nya.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/547927/original/file-20230913-21-o53nya.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/547927/original/file-20230913-21-o53nya.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/547927/original/file-20230913-21-o53nya.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/547927/original/file-20230913-21-o53nya.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/547927/original/file-20230913-21-o53nya.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/547927/original/file-20230913-21-o53nya.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/547927/original/file-20230913-21-o53nya.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">The implant (shown next to a 10-cent coin for a size comparison) is inserted into a koala when it receives its first vaccination, meaning the animal has to be captured only once.</span>
<span class="attribution"><span class="source">Kenneth Beagley</span></span>
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Read more:
<a href="https://theconversation.com/a-cull-could-help-save-koalas-from-chlamydia-if-we-allowed-it-49195">A cull could help save koalas from chlamydia, if we allowed it</a>
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<h2>How does the implant work?</h2>
<p>The implant is a polymer tube developed by the QUT team. It borrows from technology already used by the group for making polymer scaffolds to support tissue growth. The team screened a range of biodegradable polymers for ones that would degrade over just a few weeks. They also had to be flexible enough to not break prematurely when implanted beneath the skin. </p>
<p>Manufacturing the polymer pellets into tubes allows the booster vaccine to be filled into the tube. It’s similar in size to the human <a href="https://www.healthdirect.gov.au/contraceptive-implant">Implanon contraceptive implant</a>. </p>
<p>When the koala is injected with the first dose, the implant is also inserted under the skin. This starts a process of slow degradation of the implant until the walls of the tube fail and the vaccine is released as a burst. What is left of the implant dissolves as chemicals naturally found in the body. </p>
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Read more:
<a href="https://theconversation.com/a-new-3d-koala-genome-will-aid-efforts-to-defend-the-threatened-species-153873">A new 3D koala genome will aid efforts to defend the threatened species</a>
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<h2>What’s the next step?</h2>
<p>To scale up the implants we are working with a company in the United States to develop methods to manufacture thousands of implants at once. Our federal funding will allow us to fine-tune a second-generation implant to deliver the chlamydia vaccine to koalas. We will test it for safety in sheep and then evaluate the implant in captive-bred koalas at Currumbin Wildlife Sanctuary. </p>
<p>Our ultimate aim is to be able to capture a wild koala once only and test it for chlamydia. This would be done using a rapid test we have developed. The test can be done in the back of a 4WD vehicle and takes 20–30 minutes.</p>
<p>If the koala is chlamydia-free, we would then vaccinate with the implant and release the animal back into the wild.</p><img src="https://counter.theconversation.com/content/211610/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Ken Beagley receives funding from the Saving Koalas fund, the ARC and owns shares in PolVax Pty Ltd </span></em></p><p class="fine-print"><em><span>Tim Dargaville receives funding from the Saving Koalas Fund, the Australian Research Council and owns shares in PolVax Pty Ltd. </span></em></p>Chlamydia is devastating for koalas, but the vaccine to prevent infection requires a booster shot. Recapturing the animals for their booster shot is costly and stresses them, but there’s a solution.Kenneth W Beagley, Professor of Immunology, Queensland University of TechnologyTim Dargaville, Professor of Polymer Chemistry, Queensland University of TechnologyLicensed as Creative Commons – attribution, no derivatives.