tag:theconversation.com,2011:/global/topics/covid-19-vaccines-and-variants-104980/articlesCOVID-19 vaccines and variants – The Conversation2023-01-27T19:27:58Ztag:theconversation.com,2011:article/1986462023-01-27T19:27:58Z2023-01-27T19:27:58ZFDA advisory committee votes unanimously in favor of a one-shot COVID-19 vaccine approach – 5 questions answered<figure><img src="https://images.theconversation.com/files/506681/original/file-20230126-19246-l429g7.jpg?ixlib=rb-1.1.0&rect=65%2C43%2C7195%2C3766&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The FDA advisory committee discussed vaccine safety, effectiveness of the current shots, potential seasonality of COVID-19 and more.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/mutating-virus-variant-royalty-free-image/1356114754?phrase=sars-cov-2%20variants&adppopup=true">wildpixel/iStock via Getty Images Plus</a></span></figcaption></figure><p><em>The U.S. Food and Drug Administration’s key science advisory panel, the Vaccines and Related Biological Products Advisory Committee, met on Jan. 26, 2023, to chart a path forward for COVID-19 vaccine policy. During the all-day meeting, the 21-member committee discussed an array of weighty issues including the efficacy of existing vaccines, the composition of future vaccine strains and the need to match them to the circulating variants of SARS-CoV-2, the possibility of moving to an annual-shot model, the potential seasonality of the virus and much more.</em> </p>
<p><em>But the key question at hand, and the only formal question that was voted on, following a <a href="https://www.washingtonpost.com/health/2023/01/23/covid-vaccine-once-a-year/">proposal from the FDA</a> earlier in the week, had to do with how to simplify the path to getting people vaccinated.</em></p>
<p><em>The Conversation asked <a href="https://scholar.google.com/citations?user=-oDHlFYAAAAJ&hl=en">immunologist Matthew Woodruff</a>, who has been on the front lines of studying <a href="https://www.nature.com/articles/s41586-022-05273-0">immune responses to COVID-19</a> since the <a href="https://theconversation.com/an-autoimmune-like-antibody-response-is-linked-with-severe-covid-19-146255">early days of the pandemic</a>, to walk us through the big questions of the day and what they mean for future COVID-19 vaccine strategies.</em></p>
<h2>What exactly did the advisory committee vote on?</h2>
<p>The question put before the committee for a vote was whether to move to one COVID-19 vaccine consisting of a single composition for all people – whether currently vaccinated or not – and away from the current model that includes one formulation given as a primary series and a separate formulation administered as a booster. Importantly, approved formulations could come from any number of vaccine manufacturers, not just those that have currently authorized vaccines.</p>
<p>The U.S. Centers for Disease Control and Prevention currently requires that the primary series of shots, or the first two doses of the vaccine that a patient receives, consist of the first generation of vaccine against the original strain of SARS-CoV-2, known as the “Wuhan” strain of the virus. These shots are given weeks apart, followed months later by a booster shot that <a href="https://www.fda.gov/news-events/press-announcements/coronavirus-covid-19-update-fda-authorizes-moderna-pfizer-biontech-bivalent-covid-19-vaccines-use">was updated in August 2022 </a>to contain a bivalent formulation of vaccine that targets both the original viral strain and newer subvariants of omicron. </p>
<p>The committee’s endorsement simplifies those recommendations. In a 21-to-0 vote, the advisory board recommended fully replacing, or “harmonizing,” the original formulation of the vaccine with a single shot that would consist of – at least for now – the current bivalent vaccine.</p>
<p>In doing so, it has signaled its belief that these new second-generation vaccines are an upgrade over their predecessors in protecting from infection and severe illness at this point in the pandemic. </p>
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<figcaption><span class="caption">If the FDA panel’s recommendation is endorsed by the CDC, only a single composition of vaccine – in this case, the updated bivalent shot – will be used for both vaccinated and unvaccinated people.</span></figcaption>
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<h2>Will the single shot remain a mixed-strain, or bivalent, vaccine?</h2>
<p>For now, the single shot will be bivalent. But this may not always be the case.</p>
<p>There was a general agreement that the current bivalent shot is preferable to the original vaccine targeted at the Wuhan strain of the virus by itself. But committee members debated whether that original Wuhan vaccine strain should continue to be a part of updated vaccine formulations.</p>
<p>There is no current data comparing a monovalent, or single-strain, vaccine that targets omicron and its subvariants against the current bivalent shot. As a result, it’s unclear how a monovalent shot against recent omicron subvariants would perform in comparison to the bivalent version.</p>
<h2>What is immune imprinting, and how does it apply here?</h2>
<p>A main reason for the debate over monovalent versus bivalent – or, for that matter, trivalent or tetravalent – vaccines is a lack of understanding around how best to sharpen an immune response to a slightly altered threat. This has long been a debate surrounding annual influenza vaccination strategies, where studies have shown that the immune “memory” that forms in response to a prior vaccine <a href="https://doi.org/10.4049/jimmunol.0900398">can actively repress a robust immune response to the next</a>.</p>
<p>This phenomenon of immune imprinting, originally coined in 1960 as “<a href="https://www.jstor.org/stable/985534">original antigenic sin</a>,” has been a topic of debate both within the advisory committee and within the <a href="https://theconversation.com/even-bivalent-updated-covid-19-boosters-struggle-to-prevent-omicron-subvariant-transmission-an-immunologist-discusses-why-new-approaches-are-necessary-197878">broader immunological community</a>. </p>
<p>Although <a href="https://doi.org/10.1016/j.ebiom.2022.104341">innovative strategies</a> are being developed to overcome <a href="https://theconversation.com/why-we-cant-boost-our-way-out-of-the-covid-19-pandemic-for-the-long-term-181027">potential problems with routinely updated vaccines</a>, they are not yet ready to be tested in humans. In the meantime, it is unclear how bivalent versus monovalent vaccine choices might alter this phenomenon, and it is very clear that more study is needed.</p>
<h2>Is the committee considering only mRNA vaccines?</h2>
<p>While a significant portion of the discussion focused on the mRNA vaccine platform used by both Pfizer and Moderna, several committee members emphasized the need for new technologies that <a href="https://theconversation.com/even-bivalent-updated-covid-19-boosters-struggle-to-prevent-omicron-subvariant-transmission-an-immunologist-discusses-why-new-approaches-are-necessary-197878">could provide broader immunological protection</a>. Dr. Pamela McInnes, a now-retired longtime deputy director of the National Center for Advancing Translational Sciences, highlighted this point, saying, “I would make a plea for ongoing research on broader protection, maybe different platforms, maybe a different approach.”</p>
<p>A good deal of attention was also directed toward Novavax, a protein-based formulation that relies on a <a href="https://www.nytimes.com/interactive/2020/health/novavax-covid-19-vaccine.html">more traditional approach to vaccination</a> than the mRNA-based vaccines. Although the Novavax vaccine has been authorized by the FDA for use since July 2022, it has received much less national attention – largely because of its latecomer status. Nonetheless, Novavax has boasted efficacy rates <a href="https://doi.org/10.1038/s41598-023-27698-x">on par with its mRNA cousins</a>, with <a href="https://www.ama-assn.org/delivering-care/public-health/what-doctors-wish-patients-knew-about-novavax-covid-19-vaccine">good safety profiles</a> and less demanding <a href="https://www.health.gov.au/our-work/covid-19-vaccines/advice-for-providers/clinical-guidance/transporting-storing-and-handling">long-term storage requirements</a> than the mRNA shots. </p>
<p>By simplifying the vaccine schedule to include only a single vaccine formulation, the committee reasoned, it might be easier for competing vaccination platforms to break into the market. In other words, newer vaccine contenders would not have to rely on patients’ having already received their primary series before using their products. Companies seemed ready to take advantage of that future flexibility, with researchers from Pfizer, Moderna and Novavax all revealing their companies’ exploration of a hybrid COVID-19 and flu shot at various stages of clinical trials and testing.</p>
<h2>Would the single shot resemble flu vaccine development?</h2>
<p>Not necessarily. Currently, the influenza vaccine is <a href="https://www.cdc.gov/flu/prevent/vaccine-selection.htm">decided by committee</a> through the World Health Organization. Because of its seasonal nature, the strains to be included in each season’s flu vaccine for the Southern and Northern hemispheres, with their opposing winters, are selected independently. The Northern Hemisphere’s selection is made in February for the following winter based on a vast network of flu monitoring stations around the globe.</p>
<p>Although there was broad consensus among panelists that the shots against SARS-CoV-2 should be updated regularly to more closely match the most current circulating viral strain, there was less agreement on how frequent that would be. </p>
<p>For instance, rapidly mutating strains of the virus in both summer and winter surges might necessitate two updated shots a year instead of just one. As Dr. Eric Rubin, an infectious disease expert from the Harvard T.H. Chan School of Public Health, noted, “It’s hard to say that it’s going to be annual at this point.”</p><img src="https://counter.theconversation.com/content/198646/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Matthew Woodruff receives funding from the National Institute of Health and the US Department of Defense to support his academic research.</span></em></p>Many questions remain about next steps for US vaccine policy. But the FDA advisory panel’s hearty endorsement of a single-composition COVID-19 vaccine represents a pivotal step.Matthew Woodruff, Instructor of Human Immunology, Emory UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1978782023-01-25T13:25:09Z2023-01-25T13:25:09ZEven bivalent updated COVID-19 boosters struggle to prevent omicron subvariant transmission – an immunologist discusses why new approaches are necessary<figure><img src="https://images.theconversation.com/files/506017/original/file-20230124-17-uye0hb.jpg?ixlib=rb-1.1.0&rect=61%2C51%2C6816%2C3434&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The FDA is proposing an annual shot against COVID-19, signaling that a new approach is needed.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/antibodies-background-royalty-free-image/1358868801?phrase=antibodies&adppopup=true">wildpixel/iStock via Getty Images Plus</a></span></figcaption></figure><p>By almost any measure, the vaccination campaign against SARS-CoV-2, the virus that causes COVID-19, has been <a href="https://www.unicef.org/coronavirus/the-covid-19-vaccine-success-stories">a global success</a>. </p>
<p>As of January 2023, more than <a href="https://www.bloomberg.com/graphics/covid-vaccine-tracker-global-distribution/">12 billion</a> vaccines against SARS-CoV-2 have been administered in an effort that has saved countless lives – more than <a href="https://doi.org/10.1016/S1473-3099(22)00320-6">14 million</a> in the first year of vaccine availability alone. With a <a href="https://doi.org/10.1056/NEJMoa2034577">95% efficacy</a> in the prevention of severe infection and death, and better safety profiles than similar <a href="https://doi.org/10.1001/jama.294.21.2734">historically effective vaccines</a>, the biomedical community hoped that a combination of vaccination and natural immunity might bring the pandemic to a relatively quick end.</p>
<p>But the emergence of new viral variants, <a href="https://theconversation.com/will-omicron-the-new-coronavirus-variant-of-concern-be-more-contagious-than-delta-a-virus-evolution-expert-explains-what-researchers-know-and-what-they-dont-169020">particularly omicron</a> and its <a href="https://theconversation.com/how-the-omicron-subvariant-ba-5-became-a-master-of-disguise-and-what-it-means-for-the-current-covid-19-surge-187132">array of subvariants</a>, upended those expectations. The latest omicron strain, XBB.1.5. – dubbed “Kraken”, after a mythical sea creature – has rapidly become the dominant subvariant in the U.S. The World Health Organization is calling it <a href="https://www.washingtonpost.com/health/2023/01/05/new-omicron-variant-xbb15-covid-who/">the most contagious strain so far</a>, with its success almost certainly attributable to an ability to dodge immunity from previous vaccines or infections.</p>
<p>The effort to get ahead of these ever-changing variants is also in part what has led the Food and Drug Administration to <a href="https://www.statnews.com/2023/01/23/fda-scientists-propose-an-annual-covid-shot-matched-to-current-strains/?utm_campaign=daily">reconsider its approach</a> to COVID-19 vaccination. On Jan. 23, 2023, the agency proposed that current guidelines for a series of shots followed by a booster be replaced by an annual COVID-19 vaccine that is updated each year to combat current strains. The proposal is set to be reviewed by the FDA’s science advisory committee on Jan. 26.</p>
<h2>Limitations of current mRNA vaccination strategies</h2>
<p>Unfortunately, the new bivalent shots, which include components from both the original SARS-CoV-2 strain as well as a recent omicron variant, have <a href="https://doi.org/10.1056/NEJMp2215780">not performed as well</a> as some scientists had hoped. Although there is no question that the updated jabs are capable of <a href="https://doi.org/10.1056/NEJMc2214293">boosting antibody levels</a> against SARS-CoV-2 and <a href="http://dx.doi.org/10.2139/ssrn.4314067">helping to prevent severe illness and hospitalization</a>, <a href="https://doi.org/10.1101/2022.10.22.513349">several</a> <a href="https://doi.org/10.1101/2022.10.24.513619">studies</a> have suggested that they are not necessarily more capable of preventing omicron infections than their predecessors.</p>
<p>As <a href="https://scholar.google.com/citations?user=-oDHlFYAAAAJ&hl=en">an immunologist</a> who studies how the immune system <a href="https://doi.org/10.1016/j.celrep.2018.09.029">selects which antibodies to produce</a> and <a href="https://doi.org/10.1038/s41586-022-05273-0">immune responses to COVID-19</a>, these new results are disappointing. But they are not entirely unexpected. </p>
<p>When COVID-19 vaccines were being rolled out in early 2021, immunologists began having <a href="https://theconversation.com/immune-interference-why-even-updated-vaccines-could-struggle-to-keep-up-with-emerging-coronavirus-strains-156465">public discussions</a> about the potential obstacles to rapidly generating updated vaccines to emerging viral strains. At the time, there was no hard data. But researchers have known for a <a href="https://www.jstor.org/stable/985534">very long time</a> that immunological memory, the very thing that offers continued protection against a virus long after vaccination, can sometimes negatively interfere with the development of slightly <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2138235/pdf/331.pdf">updated immune responses</a>. </p>
<p>The failure of these new bivalent vaccines in widely preventing omicron infections suggests that our current approach is simply not sufficient to interrupt the viral transmission cycle driving the COVID-19 pandemic. In my view, it’s clear that innovative vaccine designs capable of producing a broader immunity are badly needed. </p>
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<figcaption><span class="caption">The latest COVID-19 subvariant, XBB.1.5, accounts for a large portion of new cases.</span></figcaption>
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<h2>Vaccines are designed to generate immune memory</h2>
<p>In simplest terms, vaccines are a way to give your immune system a sneak peek at a pathogen. <a href="https://www.vaccines.gov/basics/types">There are several different ways to do this</a>. One way is to inject inactivated versions of a virus, as has been <a href="https://www.vaccines.gov/diseases/polio">done with polio</a>. Another is to use noninfectious viral components, such as the proteins used for <a href="https://www.cdc.gov/flu/prevent/different-flu-vaccines.htm">flu vaccines</a>. </p>
<p>And most recently, scientists have found ways to deliver mRNA <a href="https://theconversation.com/what-happens-when-the-covid-19-vaccines-enter-the-body-a-road-map-for-kids-and-grown-ups-164624">“instructions” that tell your body</a> how to make those noninfectious viral components. This is the approach used with the <a href="https://www.nytimes.com/interactive/2020/health/moderna-covid-19-vaccine.html">Moderna and Pfizer vaccines</a> targeted against COVID-19.</p>
<p>The mRNA-based vaccines all train your immune system to identify and respond against critical components of a potential invader. An important part of that response is to get your body to produce antibodies that will hopefully prevent future infections, helping to break the cycle of person-to-person transmission. </p>
<p>In a successful response, the immune system will not only produce antibodies that are specific to the pathogen, but will also remember how to make them in case you encounter that same pathogen again in the future.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/506020/original/file-20230124-11-xb1ovk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Vials and syringes containing COVID-19 vaccine are displayed on a tray." src="https://images.theconversation.com/files/506020/original/file-20230124-11-xb1ovk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/506020/original/file-20230124-11-xb1ovk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/506020/original/file-20230124-11-xb1ovk.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/506020/original/file-20230124-11-xb1ovk.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/506020/original/file-20230124-11-xb1ovk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/506020/original/file-20230124-11-xb1ovk.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/506020/original/file-20230124-11-xb1ovk.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">The existing approach to COVID-19 vaccines has proved effective at preventing serious illness and death, but it has not prevented infections as well as scientists had hoped.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/vials-with-the-covid-19-vaccine-and-syringes-are-royalty-free-image/1303457369?phrase=immune%20system%20concept&adppopup=true">Morsa Images/DigitalVision via Getty Images</a></span>
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<h2>The specter of ‘original antigenic sin’</h2>
<p>But what happens when the virus evolves and that memory becomes obsolete?</p>
<p>Immunologists have wondered this <a href="https://theconversation.com/immune-interference-why-even-updated-vaccines-could-struggle-to-keep-up-with-emerging-coronavirus-strains-156465">since the initial COVID-19 vaccine rollout</a>. Recently, it has found new relevance in light of the <a href="https://www.statnews.com/2023/01/23/fda-scientists-propose-an-annual-covid-shot-matched-to-current-strains/?utm_campaign=daily">FDA’s proposal</a> for an updated annual COVID-19 shot. </p>
<p>While it is possible that immune responses to updated vaccines will <a href="https://doi.org/10.1016/j.it.2022.02.009">simply replace the old ones</a>, that has not been true for influenza. With flu, researchers have learned that preexisting immunity to one strain <a href="https://doi.org/10.4049/jimmunol.0900398">can actively inhibit</a> the ability to respond well against another.</p>
<p>Put in everyday language, think of a virus as a car trying to run you over. You might produce one kind of antibody against the hood, one against the bumper and one against the hubcaps that prevents the wheels from turning. You have produced three kinds of antibodies specific to the car, but it turns out that only the hubcap antibodies effectively slow it down.</p>
<p>Now the car mutates, like SARS-CoV-2 has. It changes the shape of the hubcaps or it removes them altogether. Your immune system still recognizes the car, but not the hubcaps. The system doesn’t know that the hubcap was the only effective target, so it ignores the hubcaps and ramps up its attack on the hood and bumper. </p>
<p>In ignoring the new hubcap response, the immune system’s memory of the original car is not only obsolete, but it is also actively interfering with the response necessary to target the new car’s wheels. This is what immunologists call “<a href="https://doi.org/10.4049/jimmunol.1801149">original antigenic sin</a>” – ineffective immune memory that hampers desired responses to new pathogen strains.</p>
<p>This sort of interference has been extremely difficult to quantify and study in humans, although it may become easier with the <a href="https://www.washingtonpost.com/health/2023/01/23/covid-vaccine-once-a-year/">FDA’s proposal</a>. A once-yearly approach to COVID-19 vaccination opens the door for more straightforward studies on how memory to each vaccine influences the next.</p>
<h2>Multi-strain vaccinations offer hope</h2>
<p>Simultaneously, <a href="https://www.niaidcivics.org/">significant efforts</a> are being made to prioritize the pursuit of a single-shot or “universal” vaccine. One approach has been to take advantage of emerging research showing that if your immune system is presented with multiple versions of the same pathogen, it will tend to <a href="https://doi.org/10.1016/j.celrep.2018.09.029">choose targets that are shared between them</a>. </p>
<p>Presented with a Model T, Ford F-150 and electric Mustang all at once, your immune system will often choose to ignore differences like the hubcaps in favor of similarities like the shape and rubber on the tires. Not only would this interfere with the function of all three vehicles, but it could theoretically interfere with most road-based vehicles – or viral threats such as variants.</p>
<p>Researchers have begun making rapid headway using this approach with the development of <a href="https://doi.org/10.1038/s41591-020-1118-7">complex multi-strain flu vaccines</a> that are performing well in early clinical trials. New studies focused on SARS-CoV-2 <a href="https://doi.org/10.1016/j.ebiom.2022.104341">hope to do the same</a>. Persistent pathogens including <a href="https://doi.org/10.1186/s12985-017-0918-y">influenza</a> and <a href="https://doi.org/10.1038/ni.3158">HIV</a> all suffer from versions of the same antibody-targeting issues. It is possible that this pandemic may serve as a crucible of innovation that leads to the next generation of infectious disease prevention.</p>
<p><em>This is an updated version of an article <a href="https://theconversation.com/immune-interference-why-even-updated-vaccines-could-struggle-to-keep-up-with-emerging-coronavirus-strains-156465">originally published on March 8, 2021</a>.</em></p><img src="https://counter.theconversation.com/content/197878/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Matthew Woodruff 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 new bivalent boosters against COVID-19 have failed to halt omicron infections. However, new technologies are being developed that pave a way forward.Matthew Woodruff, Instructor of Human Immunology, Emory UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1850072022-06-17T18:38:51Z2022-06-17T18:38:51ZAt last, COVID-19 shots for little kids – 5 essential reads<figure><img src="https://images.theconversation.com/files/468928/original/file-20220615-24-8k5pqs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Millions of U.S. children between the ages of 6 months and 4 years will soon be eligible for COVID-19 shots. </span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/getting-a-bandage-after-a-vaccine-royalty-free-image/1358496301?adppopup=true">FatCamera/E+ via Getty Images</a></span></figcaption></figure><p>For many parents of kids under age 5, a safe and effective COVID-19 vaccine could not come soon enough. A full year and a half after shots first became available for adults, their wait is nearly over. </p>
<p>On June 17, 2022, the Food and Drug Administration <a href="https://www.fda.gov/news-events/press-announcements/coronavirus-covid-19-update-fda-authorizes-moderna-and-pfizer-biontech-covid-19-vaccines-children">authorized both the Pfizer-BioNTech and Moderna COVID-19 shots</a> for the nearly 20 million U.S. children between the ages of 6 months and 4 years. The widely anticipated decision follows <a href="https://www.statnews.com/2022/06/15/tracking-an-fda-advisory-panel-meeting-on-covid-vaccines-in-young-children/">a unanimous recommendation in favor of the shots</a> by the FDA’s independent advisory panel. </p>
<p>The remaining critical step is for the <a href="https://www.nytimes.com/2022/06/17/health/cdc-kids-vaccines.html">Centers for Disease Control and Prevention to sign off on the shots</a>, which is expected to take place within days. </p>
<p>The following collection of articles from The Conversation’s archives traces the winding path of the development of COVID-19 vaccines for the youngest children, from the early days of clinical trials to the practical challenges of how to help kids overcome their fears and anxieties over getting a shot.</p>
<h2>1. ‘Kids aren’t just littler adults’</h2>
<p>As the delta variant raged across the country in the summer of 2021, parents of kids under age 12 were anxiously awaiting the availability of a safe and effective COVID-19 shot for that age group. The FDA’s authorization for ages 5 to 11 finally came in October 2021. But that still left the preschool and younger kids waiting for their own version of the vaccine.</p>
<p>In July 2021, Judy Martin, <a href="https://www.cvr.pitt.edu/people/judy-martin-md">a professor of pediatrics</a> at the University of Pittsburgh Health Sciences, <a href="https://theconversation.com/kids-arent-just-littler-adults-heres-why-they-need-their-own-clinical-trials-for-a-covid-19-vaccine-162821">helped pull back the curtain</a> for our readers on the often mysterious and slow-going clinical research studies that must take place before vaccines are authorized for children. Martin explained how the developing brains, bodies and immune systems of infants and young children differ from those of older children, and how that is taken into account during vaccine development, clinical trials and safety assessment.</p>
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Read more:
<a href="https://theconversation.com/kids-arent-just-littler-adults-heres-why-they-need-their-own-clinical-trials-for-a-covid-19-vaccine-162821">Kids aren't just littler adults – here's why they need their own clinical trials for a COVID-19 vaccine</a>
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<h2>2. So you get a shot, then what?</h2>
<p>The COVID-19 pandemic has turned a lot of once-obscure biology terms such as <a href="https://theconversation.com/what-is-mrna-the-messenger-molecule-thats-been-in-every-living-cell-for-billions-of-years-is-the-key-ingredient-in-some-covid-19-vaccines-158511">mRNA</a>, <a href="https://www.sciencenewsforstudents.org/article/explainer-what-is-a-spike-protein">spike proteins</a> and “waning antibodies” into household words. Yet for all the talk of vaccines and immunology, few people have a deep understanding of just what exactly happens once a vaccine is injected into the body. </p>
<p>One curious 12-year-old posed that very question to The Conversation: “How does a COVID-19 vaccine work in the body?” So we asked Glenn J. Rapsinski, a <a href="https://www.pediatrics.pitt.edu/people/glenn-j-rapsinski-md-phd">pediatric infectious diseases expert</a> at the University of Pittsburgh Health Sciences, <a href="https://theconversation.com/what-happens-when-the-covid-19-vaccines-enter-the-body-a-road-map-for-kids-and-grown-ups-164624">to tackle that question</a> for our <a href="https://theconversation.com/us/topics/curious-kids-us-74795">Curious Kids series</a> – at a level that young kids and adults alike can appreciate. </p>
<p>When the body encounters the molecules in a COVID-19 vaccine – which mimics the SARS-CoV-2 virus – it activates an intricate and coordinated set of cells and processes. It’s a lot like an elaborate construction zone. Some of these cells alert the body to the invader and recruit helpers, flagging the invader with signals akin to “flashing neon yellow signs.” </p>
<p>“As all of these important processes are happening inside your body, you might see some physical signs that there’s a struggle going on underneath the skin,” Rapsinski explained. “If your arm gets sore after you get the shot, it’s because immune cells like the dendritic cells, T-cells and B-cells are racing to the arm to inspect the threat.”</p>
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Read more:
<a href="https://theconversation.com/what-happens-when-the-covid-19-vaccines-enter-the-body-a-road-map-for-kids-and-grown-ups-164624">What happens when the COVID-19 vaccines enter the body – a road map for kids and grown-ups</a>
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<a href="https://images.theconversation.com/files/469064/original/file-20220615-18-ejjivp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A schematic diagram demonstrating the roles of B-cells and T-cells in the immune response." src="https://images.theconversation.com/files/469064/original/file-20220615-18-ejjivp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/469064/original/file-20220615-18-ejjivp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=592&fit=crop&dpr=1 600w, https://images.theconversation.com/files/469064/original/file-20220615-18-ejjivp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=592&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/469064/original/file-20220615-18-ejjivp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=592&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/469064/original/file-20220615-18-ejjivp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=744&fit=crop&dpr=1 754w, https://images.theconversation.com/files/469064/original/file-20220615-18-ejjivp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=744&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/469064/original/file-20220615-18-ejjivp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=744&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">When the body encounters a perceived threat, such as an actual SARS-CoV-2 virus or a vaccine that mimics it, B-cells and T-cells spring into action alongside a sophisticated chorus of other cells.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/illustration/cells-and-t-cells-schematic-diagram-vector-royalty-free-illustration/907993572?adppopup=true">VectorMine/iStock via Getty Images Plus</a></span>
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<h2>3. Training the immune system</h2>
<p>As clinical trials of COVID-19 shots for children under age 5 crawled along in early 2022, the omicron variant gained a firm foothold in the U.S. While serious cases of COVID-19 remain relatively rare in children, hospitalizations in kids under 5 increased dramatically due to the heightened transmissibility of omicron, highlighting the urgent need for a safe vaccine in that age group.</p>
<p>Debbie-Ann Shirley, a <a href="https://uvahealth.com/findadoctor/profile/debbie-ann-shirley">pediatrician specializing in infectious diseases</a> at the University of Virginia, wrote in March 2022 about the <a href="https://theconversation.com/covid-19-vaccines-for-the-youngest-children-may-be-inching-closer-to-authorization-a-pediatrician-explains-how-theyre-being-tested-176774">painstaking process of performing clinical trials</a> sequentially for each descending age group. </p>
<p>“Several factors determine how our bodies respond to vaccines, and one of these variables is age,” Shirley explained. “Testing by age groups helps to account for these differences in how the maturing immune system responds to different types of vaccines. It is common for childhood vaccines to be given in series to help train the young immune response to make better and stronger antibody responses with each subsequent dose.” </p>
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Read more:
<a href="https://theconversation.com/covid-19-vaccines-for-the-youngest-children-may-be-inching-closer-to-authorization-a-pediatrician-explains-how-theyre-being-tested-176774">COVID-19 vaccines for the youngest children may be inching closer to authorization – a pediatrician explains how they're being tested</a>
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<h2>4. The inevitable booster shot question</h2>
<p>In the fall of 2021, a mounting body of data from adults and adolescents found that immunity from COVID-19 vaccines and infections was waning over time, suggesting that booster shots would be needed – especially in the face of omicron. The same trends proved true for the 5 to 11 age group, though vaccination continued to provide strong protection against severe COVID-19 that leads to hospitalization. So in May 2022, the CDC recommended a booster dose for 5- to 11-year-olds.</p>
<p>COVID-19 shots for infants and preschoolers are expected to follow a similar trajectory; Pfizer’s COVID-19 shots for kids under age 5 are intended to be a three-dose series. Moderna’s testing of the third dose is still underway. In May 2022, Shirley provided a <a href="https://theconversation.com/how-important-is-the-covid-19-booster-shot-for-5-to-11-year-olds-5-questions-answered-183427">snapshot of those studies</a> and explained how researchers were determining that the third shots were safe and effective. </p>
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Read more:
<a href="https://theconversation.com/how-important-is-the-covid-19-booster-shot-for-5-to-11-year-olds-5-questions-answered-183427">How important is the COVID-19 booster shot for 5-to-11-year-olds? 5 questions answered</a>
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<h2>5. Helping kids overcome fear of shots</h2>
<p>While the wait for COVID-19 vaccines for young children has undoubtedly been excruciating for some parents, so might be their conversations with children who have serious anxiety over getting a shot. Lynn Gardner, an <a href="https://msm.edu/about_us/FacultyDirectory/Pediatrics/LynnGardner/index.php">associate professor of pediatrics</a> at Morehouse School of Medicine and a primary care pediatrician, has helped thousands of parents and their children cope with the very real fears that can surface in the doctor’s office.</p>
<p>Gardner wrote about <a href="https://theconversation.com/kids-afraid-of-getting-shots-here-are-3-easy-ways-for-parents-to-help-them-177025">what she calls the “Three P’s</a>” – preparation, proximity and praise – that parents and caregivers can use to lessen their children’s anxiety around shots and help them have a more positive experience. </p>
<p>“It is essential that you ask your child how they are feeling about receiving a shot,” she explained. “Giving them the opportunity to express their feelings can decrease the amount of stress and anxiety they feel about it. Validate their feelings by telling them you know needles can be a bit scary, but then reassure them that they can handle it. Explain why they’re receiving vaccines and emphasize it is for their overall good.”</p>
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Read more:
<a href="https://theconversation.com/kids-afraid-of-getting-shots-here-are-3-easy-ways-for-parents-to-help-them-177025">Kids afraid of getting shots? Here are 3 easy ways for parents to help them</a>
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<p><em>Editor’s note: This story is a roundup of articles from The Conversation’s archives.</em></p><img src="https://counter.theconversation.com/content/185007/count.gif" alt="The Conversation" width="1" height="1" />
The FDA’s authorization of COVID-19 shots for children ages 6 months to 4 years will bring relief for millions of parents. Pending CDC endorsement, shots for this group will be available within days.Amanda Mascarelli, Senior Health and Medicine EditorLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1812332022-06-02T12:17:20Z2022-06-02T12:17:20ZFuture COVID-19 booster shots will likely need fresh formulations as new coronavirus variants of concern continue to emerge<figure><img src="https://images.theconversation.com/files/466619/original/file-20220601-48323-a2yi45.jpg?ixlib=rb-1.1.0&rect=685%2C319%2C6350%2C4931&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Viral surveillance and prediction may be key parts of figuring out what goes into a vaccine.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/close-up-of-syringe-with-bottles-on-table-pakistan-royalty-free-image/1342313994">Pexels Cover/500px via Getty Images</a></span></figcaption></figure><p>Being up to date on COVID-19 vaccines means having <a href="https://www.cdc.gov/coronavirus/2019-ncov/vaccines/booster-shot.html">had three or four doses</a> of the same shot at this point. Current boosters are the same formulations as the first authorized shots, <a href="https://www.nature.com/articles/d41586-021-02854-3">based on the original strain of the coronavirus</a> that emerged in late 2019. <a href="https://www.cdc.gov/coronavirus/2019-ncov/vaccines/effectiveness/work.html">They do still protect</a> against severe COVID-19, hospitalizations and deaths. But as immunity wanes over time and new, more contagious SARS-CoV-2 variants emerge, the world needs a long-term boosting strategy.</p>
<p><a href="https://scholar.google.com/citations?user=v61MWbsAAAAJ&hl=en&oi=ao">I’m an immunologist</a> who studies immunity to viruses. I was a part of the teams that <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">helped develop the Moderna</a> and <a href="https://theconversation.com/how-does-the-johnson-and-johnson-vaccine-compare-to-other-coronavirus-vaccines-4-questions-answered-155944">Johnson & Johnson SARS-CoV-2 vaccines</a>, and <a href="https://theconversation.com/what-monoclonal-antibodies-are-and-why-we-need-them-as-well-as-a-vaccine-149356">the monoclonal antibody therapies</a> from Eli Lilly and AstraZeneca.</p>
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<a href="https://images.theconversation.com/files/466621/original/file-20220601-48889-avwg9y.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="out of focus smiling woman extends her arm holding vaccination record card" src="https://images.theconversation.com/files/466621/original/file-20220601-48889-avwg9y.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/466621/original/file-20220601-48889-avwg9y.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=692&fit=crop&dpr=1 600w, https://images.theconversation.com/files/466621/original/file-20220601-48889-avwg9y.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=692&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/466621/original/file-20220601-48889-avwg9y.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=692&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/466621/original/file-20220601-48889-avwg9y.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=870&fit=crop&dpr=1 754w, https://images.theconversation.com/files/466621/original/file-20220601-48889-avwg9y.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=870&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/466621/original/file-20220601-48889-avwg9y.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=870&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">How many lines will ultimately be filled out on your COVID-19 vaccination card?</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/vaccination-cart-royalty-free-image/1347369341">LPETTET/E+ via Getty Images</a></span>
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<p>I often get asked how frequently, or infrequently, I think people are likely to need COVID-19 booster shots in the future. No one has a crystal ball to see which SARS-CoV-2 variant will come next or how good future variants will be at evading vaccine immunity. But looking to other respiratory viral foes that have troubled humanity for a while can suggest what the future could look like. </p>
<p>Influenza virus provides one example. It’s endemic in humans, meaning it hasn’t disappeared and continues to cause recurrent seasonal waves of infection in the population. Every year officials try to predict the best formulation of a flu shot to reduce the risk of severe disease.</p>
<p>As SARS-CoV-2 continues to evolve and is <a href="https://theconversation.com/is-covid-19-here-to-stay-a-team-of-biologists-explains-what-it-means-for-a-virus-to-become-endemic-168462">likely to become endemic</a>, it is possible people may need periodic booster shots for the foreseeable future. I suspect scientists will eventually need to update the COVID-19 vaccine to take on newer variants, as they do for flu.</p>
<h2>Forecasting flu, based on careful surveillance</h2>
<p>Influenza virus surveillance offers a potential model for how SARS-CoV-2 could be tracked over time. Flu viruses have caused several pandemics, including the one in 1918 that killed <a href="https://theconversation.com/10-misconceptions-about-the-1918-flu-the-greatest-pandemic-in-history-133994">an estimated 50 million people worldwide</a>. Every year there are seasonal outbreaks of flu, and every year officials encourage the public to <a href="https://www.cdc.gov/flu/prevent/flushot.htm">get their flu shots</a>.</p>
<p>Each year, health agencies including the World Health Organization’s <a href="https://www.who.int/initiatives/global-influenza-surveillance-and-response-system">Global Influenza Surveillance and Response System</a> make an educated guess based on the flu strains circulating in the Southern Hemisphere about which ones are most likely to circulate in the Northern Hemisphere’s upcoming flu season. Then large-scale vaccine production begins, based on the selected flu strains.</p>
<p>Some flu seasons, the vaccine doesn’t turn out to be a <a href="https://www.cdc.gov/flu/vaccines-work/past-seasons-estimates.html">great match with the virus strains</a> that end up circulating most widely. Those years, the shot is not as good at preventing severe illness. While this prediction process is far from perfect, the flu vaccine field has benefited from strong viral surveillance systems and a concerted international effort by public health agencies to prepare.</p>
<p>While the particulars for influenza and SARS-CoV-2 viruses are different, I think the COVID-19 field should think about adopting similar surveillance systems in the long term. Staying on top of what strains are circulating will help researchers update the SARS-CoV-2 vaccine to match up-to-date coronavirus variants.</p>
<h2>How SARS-CoV-2 has evolved so far</h2>
<p>SARS-CoV-2 faces an evolutionary quandary as it reproduces and spreads from person to person. The virus needs to maintain its ability to get into human cells using its spike protein, while still changing in ways that allow it to evade vaccine immunity. Vaccines are designed to get your body to recognize a particular spike protein, so the more it changes, the higher the chance that the vaccine will be ineffective against the new variant.</p>
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<p>Despite these challenges, SARS-CoV-2 and its variants have successfully evolved to be more transmissible and to better evade people’s immune responses. Over the course of the COVID-19 pandemic, a <a href="https://www.theatlantic.com/science/archive/2022/03/new-covid-variant-mitigation/626980/">new SARS-CoV-2 variant of concern has emerged and dominated</a> transmission in a series of contagion waves every four to seven months. Almost like clockwork, the D614G variant emerged in the spring of 2020 and overtook the original SARS-CoV-2 outbreak strain. In late 2020 and early 2021, the alpha variant emerged and dominated transmission. In mid-2021, the delta variant overtook alpha and then dominated transmission until it was displaced by the omicron variant at the end of 2021.</p>
<p>There’s no reason to think this trend won’t continue. In the coming months, the world may see a dominant <a href="https://www.bloomberg.com/news/articles/2022-04-30/omicron-sublineages-can-evade-antibodies-from-earlier-infections">descendant of the various omicron subvariants</a>. And it’s certainly possible a new variant will emerge from a nondominant pool of SARS-CoV-2, which is how omicron itself came to be.</p>
<p>Current booster shots are simply additional doses of the vaccines based on the outbreak SARS-CoV-2 virus strain that has long been extinct. The coronavirus variants have changed a lot from the original virus, which doesn’t bode well for continued vaccine efficacy. The idea of tailor-made annual shots – like the flu vaccine – sounds appealing. The problem is that scientists haven’t yet been able to predict what the next SARS-CoV-2 variant will be with any degree of confidence.</p>
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<a href="https://images.theconversation.com/files/466624/original/file-20220601-48861-v4usft.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="people walk near a tent marked 'Vaccines | Boosters'" src="https://images.theconversation.com/files/466624/original/file-20220601-48861-v4usft.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/466624/original/file-20220601-48861-v4usft.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/466624/original/file-20220601-48861-v4usft.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/466624/original/file-20220601-48861-v4usft.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/466624/original/file-20220601-48861-v4usft.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/466624/original/file-20220601-48861-v4usft.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/466624/original/file-20220601-48861-v4usft.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">Periodic booster shots may be in order for the foreseeable future.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/covid-vaccine-and-testing-site-is-set-up-outside-of-yankee-news-photo/1390355456">Spencer Platt/Getty Images</a></span>
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<h2>Planning for the future</h2>
<p>Yes, the dominant SARS-CoV-2 variants in the upcoming fall and winter seasons may look different from the omicron subvariants currently circulating. But an updated booster that more closely resembles today’s omicron subvariants, coupled with the immunity people already have from the first vaccines, will likely offer better protection going forward. It might require less frequent boosting – at least as long as omicron sublineages continue to dominate.</p>
<p>The Food and Drug Administration is set to meet in the coming weeks to decide what the fall boosters should be in time for manufacturers to produce the shots. Vaccine makers like Moderna are currently testing their booster candidates in people and <a href="https://thehill.com/policy/healthcare/3473235-moderna-expects-large-amounts-of-omicron-booster-available-by-fall/">evaluating the immune response against newly emerging variants</a>. The test results will likely decide what will be used in anticipation of a fall or winter surge. </p>
<p>Another possibility is to pivot the vaccine booster strategy to include universal coronavirus vaccine approaches that already look promising in animal studies. Researchers are working toward what’s called a universal vaccine which would be effective against multiple strains. Some focus on <a href="https://doi.org/10.1126/science.abi4506">chimeric spikes</a>, which fuse parts of the spike of different coronaviruses together in one vaccine, to broaden protective immunity. <a href="https://clinicaltrials.gov/ct2/show/NCT04784767">Others are experimenting with</a> <a href="https://doi.org/10.1038/s41586-021-03594-0">nanoparticle vaccines</a> that get the immune system to focus on the most vulnerable regions within the coronavirus spike.</p>
<p>These strategies have been shown to ward off difficult-to-stop SARS-CoV-2 variants in lab experiments. They also work in animals against the original SARS virus that caused an outbreak in the early 2000s as well as zoonotic coronaviruses from bats that could jump into humans, causing a future SARS-CoV-3 outbreak.</p>
<p>Science has provided multiple safe and effective vaccines that reduce the risk of severe COVID-19. Reformulating booster strategies, either toward universal-based vaccines or updated boosters, can help steer us out of the COVID-19 pandemic.</p><img src="https://counter.theconversation.com/content/181233/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>David R. Martinez receives funding from the National Institutes of Health, the Howard Hughes Medical Institute, and the Burroughs Wellcome Fund.</span></em></p>A new generation of vaccines and boosters against SARS-CoV-2 may take a page from the anti-influenza playbook, with shots periodically tailored to target the most commonly circulating virus strains.David R. Martinez, Postdoctoral Fellow in Epidemiology, University of North Carolina at Chapel HillLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1727362021-11-28T01:30:19Z2021-11-28T01:30:19ZTravel bans aren’t the answer to stopping new COVID variant Omicron<figure><img src="https://images.theconversation.com/files/434230/original/file-20211127-19-3hc1k0.jpg?ixlib=rb-1.1.0&rect=0%2C8%2C5388%2C3546&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.who.int/news/item/26-11-2021-classification-of-omicron-(b.1.1.529)-sars-cov-2-variant-of-concern">Shutterstock</a></span></figcaption></figure><p>There is global concern and widespread alarm at the discovery of SARS-CoV-2 variant B.1.1.529, which the World Health Organization (WHO) has called Omicron. </p>
<p>The <a href="https://www.who.int/news/item/26-11-2021-classification-of-omicron-(b.1.1.529)-sars-cov-2-variant-of-concern">WHO classified Omicron</a> as a “variant of concern” because it has a wide range of mutations. This suggests vaccines and treatments could be less effective. </p>
<p>Although early days, Omicron appears to be able to reinfect people more easily than other strains. </p>
<p>Australia has followed other countries and regions – including the United States, Canada, United Kingdom and the European Union – and <a href="https://www.abc.net.au/news/2021-11-27/new-quarantine-rules-omicron-covid-variant-australia/100656016">banned travellers</a> from nine southern African countries. </p>
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Read more:
<a href="https://theconversation.com/omicron-is-the-new-covid-kid-on-the-block-five-steps-to-avoid-ten-to-take-immediately-172739">Omicron is the new COVID kid on the block: five steps to avoid, ten to take immediately</a>
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<p>Australians <a href="https://www.abc.net.au/news/2021-11-27/new-quarantine-rules-omicron-covid-variant-australia/100656016">seeking to return home from southern Africa</a> will still be able to do so. But they will enter hotel quarantine and be tested. Those who have returned from the nine countries – South Africa, Namibia, Zimbabwe, Botswana, Lesotho, Eswatini, the Seychelles, Malawi and Mozambique – in the past 14 days will have to isolate.</p>
<p>But Omicron has already been detected in other regions, including the UK, Germany, Israel, Hong Kong and Belgium. So while a travel ban on southern African countries may slow the spread and buy limited time, it’s unlikely to stop it. </p>
<p>As the Australian government and others act to protect their own citizens, this should be accompanied by additional resources to support countries in southern Africa and elsewhere that take prompt action. </p>
<h2>When was Omicron detected?</h2>
<p>The variant was identified on November 22 in South Africa, from a sample collected from a patient on <a href="https://www.who.int/news/item/26-11-2021-classification-of-omicron-(b.1.1.529)-sars-cov-2-variant-of-concern">November 9</a>. </p>
<p>South African virologists took prompt action, conferred with colleagues through the <a href="https://www.ngs-sa.org/ngs-sa_network_for_genomic_surveillance_south_africa/">Network of Genomic Surveillance in South Africa</a>, liaised with government, and notified the World Health Organization on November 24. </p>
<p>This is in keeping with the <a href="https://www.who.int/health-topics/international-health-regulations#tab=tab_1">International Health Regulations</a> that guide how countries should respond. </p>
<p>The behaviour of this new variant is still unclear. Some have claimed the rate of growth of Omicron infections, which reflects its transmissibility, may be even higher than those of the Delta variant. This “growth advantage” is yet to be proven but is concerning. </p>
<h2>‘Kneejerk’ response vs WHO recommendations</h2>
<p>African scientists and politicians <a href="https://www.theguardian.com/world/2021/nov/26/south-africa-b11529-covid-variant-vaccination">have been disappointed</a> in what they see as a “kneejerk” response from countries imposing travel bans. They argue the bans will have significant negative effects for the South African economy, which traditionally welcomes global tourists over the summer year-end period. </p>
<p>They note it is still unclear whether the new variant originated in South Africa, even if it was first identified there. As Omicron has already been detected in several other countries, it may already be circulating in regions not included in the travel bans. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1464653511560470532"}"></div></p>
<p>Travel bans on countries detecting new variants, and the subsequent economic costs, may also act as a disincentive for countries to reveal variants of concern in future. </p>
<p>The WHO <a href="https://www.who.int/news-room/articles-detail/updated-who-recommendations-for-international-traffic-in-relation-to-covid-19-outbreak">does not generally recommend</a> flight bans or other forms of travel embargoes. Instead, it argues interventions of proven value should be prioritised: vaccination, hand hygiene, physical distancing, well-fitted masks, and good ventilation. </p>
<p>In response to variants of concern, the WHO calls on all countries to enhance surveillance and sequencing, report initial cases or clusters, and undertake investigations to improve understanding of the variant’s behaviour.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1464301533995147270"}"></div></p>
<p>Omicron must be taken seriously. Its features are worrying, but there are large gaps in our current knowledge. While further analyses are undertaken, the variant should be controlled with testing, tracing, isolation, applying known public health measures, and ongoing surveillance. </p>
<h2>What can wealthier countries do to help?</h2>
<p>Wealthy countries such as Australia should support African nations and others to share early alerts of potentially serious communicable disease threats, and help mitigate these threats. </p>
<p>As the <a href="https://theindependentpanel.org/mainreport/">Independent Panel for Pandemic Preparedness and Response</a> noted in May:</p>
<blockquote>
<p>[…] public health actors only see downsides from drawing attention to an outbreak that has the potential to spread. </p>
</blockquote>
<p>The panel recommended creating incentives to reward early response action. This could include support to:</p>
<ul>
<li>establish research and educational partnerships</li>
<li>strengthen health systems and communicable disease surveillance</li>
<li>greatly improve vaccine availability, distribution, and equity<br></li>
<li>consider financial compensation, through some form of solidarity fund against pandemic risk.</li>
</ul>
<h2>Boosting vaccine coverage is key</h2>
<p>Vaccines remain the mainstay of protection against the most severe effects of COVID-19. </p>
<p>It’s unclear how effective vaccines will be against Omicron, but some degree of protection is presumed likely. Pfizer has also indicated it could develop an effective vaccine against a new variant such as <a href="https://www.independent.co.uk/news/health/omicron-variant-covid-vaccine-tweaked-b1965155.html">Omicron within 100 days or so</a>. </p>
<p>COVID’s persistence is partly attributable to patchy immunisation coverage across many parts of the world, notably those least developed. South Africa itself is better off than most countries on the continent, yet only <a href="https://ourworldindata.org/covid-vaccinations">24% of the adult population are currently fully vaccinated</a>. For the whole of Africa, this drops to only 7.2%. </p>
<p>Greater global support is urgently needed to boost these vaccination rates.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/yes-export-bans-on-vaccines-are-a-problem-but-why-is-the-supply-of-vaccines-so-limited-in-the-first-place-156569">Yes, export bans on vaccines are a problem, but why is the supply of vaccines so limited in the first place?</a>
</strong>
</em>
</p>
<hr>
<p>African institutions and leaders, supported by global health and vaccine experts, have argued for mRNA vaccine manufacturing facilities on the African continent. These would prioritise regional populations, overcome supply-chain problems, and respond in real time to emerging disease threats. </p>
<p>Yet developing nations face <a href="https://www.theguardian.com/australia-news/2021/nov/25/australian-government-trying-to-have-it-both-ways-on-covid-vaccine-ip-waiver">significant barriers</a> to obtaining intellectual property around COVID-19 vaccine development and production. </p>
<p>While there is still much to learn about the behaviour and impact of Omicron, the global community must demonstrate and commit real support to countries that do the right thing by promptly and transparently sharing information.</p><img src="https://counter.theconversation.com/content/172736/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Anthony Zwi 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>Given the Omicron variant has already spread beyond southern Africa, a ban on travellers from those countries will slow the spread and buy crucial time, but won’t stop this strain in its tracks.Anthony Zwi, Professor of Global Health and Development, UNSW SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1668692021-09-10T16:53:10Z2021-09-10T16:53:10ZOver-the-counter rapid antigen tests can help slow the spread of COVID-19 – here’s how to use them effectively<figure><img src="https://images.theconversation.com/files/420358/original/file-20210909-8898-1dz0a4h.jpg?ixlib=rb-1.1.0&rect=36%2C27%2C5991%2C3913&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Rapid antigen COVID-19 tests, designed for use at home, can show results in 15 minutes. </span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/woman-at-home-using-a-nasal-swab-for-covid-19-royalty-free-image/1306947463?adppopup=true">Ellen Moran via Getty Images</a></span></figcaption></figure><p>The rise of the <a href="https://theconversation.com/what-are-covid-19-variants-and-how-can-you-stay-safe-as-they-spread-a-doctor-answers-5-questions-163697">highly transmissible delta variant</a> <a href="https://www.washingtonpost.com/nation/2021/09/07/covid-delta-variant-live-updates/">around the U.S.</a> has increased demand for <a href="https://theconversation.com/rapid-screening-tests-that-prioritize-speed-over-accuracy-could-be-key-to-ending-the-coronavirus-pandemic-143882">rapid antigen COVID-19 tests</a> that can be purchased from a pharmacy <a href="https://www.cdc.gov/coronavirus/2019-ncov/testing/self-testing.html">without a prescription</a>, used at home, school or work and that give results in 15 minutes. </p>
<p>On Sept. 9, 2021, the White House announced <a href="https://www.whitehouse.gov/covidplan/">several initiatives</a> to improve access to rapid antigen tests: It will use the <a href="https://www.cfr.org/in-brief/what-defense-production-act">Defense Production Act</a> to boost the production of tests, require retailers to sell rapid tests at cost, distribute free rapid tests to community health centers and food banks and expand free testing in pharmacies.</p>
<p>Rapid antigen testing makes it much easier to get tested for COVID-19, which helps detect infectious cases before they spread. But many people are still unsure of how best to use these tests and whether they are accurate enough to be useful.</p>
<p>There are several FDA-approved rapid tests on the market including <a href="https://www.abbott.com/corpnewsroom/diagnostics-testing/BinaxNOW-what-you-need-to-know.html">Abbott BinaxNow</a>, <a href="https://www.ellumehealth.com/products/consumer-products/covid-home-test/">Ellume</a> and <a href="https://quickvueathome.com/">Quidel QuickVue</a>. These cost as little as $7-12 each and can be used to test adults and children aged 2 and up, regardless of whether they have symptoms. </p>
<p>Rapid antigen tests have a big advantage over lab-based <a href="https://my.clevelandclinic.org/health/diagnostics/21462-covid-19-and-pcr-testing">PCR testing</a> in terms of speed and convenience. Getting results in 15 minutes rather than waiting a day or more for PCR test results means it’s possible to identify COVID-19 cases right away and take precautions to prevent transmission. Having rapid testing available <a href="https://theconversation.com/fda-authorized-first-over-the-counter-covid-19-test-useful-but-not-a-game-changer-152208">over-the-counter</a> means that a lot more people will get tested since the test is <a href="https://theconversation.com/will-the-new-15-minute-covid-19-test-solve-us-testing-problems-145285">easy to perform</a> and far more convenient than PCR testing. So rapid tests can catch a lot more COVID-19 cases overall than relying only on PCR testing.</p>
<p>As a <a href="https://twitter.com/ZoeMcLaren">health economist</a> who studies <a href="https://publicpolicy.umbc.edu/zoe-m-mclaren/">public health policy</a> to combat <a href="https://scholar.google.com/citations?hl=en&user=t6ZtGJwAAAAJ">infectious disease epidemics</a>, I know that making COVID-19 testing <a href="https://theconversation.com/making-coronavirus-testing-easy-accurate-and-fast-is-critical-to-ending-the-pandemic-the-us-response-is-falling-far-short-142366">accessible, accurate and fast</a> is critical to slowing transmission of the virus and helping everyone resume normal activities safely.</p>
<h2>How accurate are rapid antigen tests?</h2>
<p>Two types of rapid tests are used for detecting an active COVID-19 infection: rapid antigen tests that detect viral proteins using a paper strip and <a href="https://www.fda.gov/consumers/consumer-updates/coronavirus-disease-2019-testing-basics">rapid molecular tests</a> – including PCR – that detect viral genetic material using a medical device.</p>
<p>It’s important to remember that rapid antigen tests serve a different purpose than PCR testing, which is considered the gold standard even though it isn’t <a href="https://doi.org/10.1186/s12985-021-01489-0">100% accurate</a>. Rapid tests are designed to identify cases with a high enough viral load in the nasal passage to be transmissible – not to diagnose all COVID-19 cases. The <a href="https://www.abbott.com/corpnewsroom/diagnostics-testing/BinaxNOW-what-you-need-to-know.html">Abbott BinaxNOW</a> rapid antigen test may only detect <a href="https://www.fda.gov/media/147254/download">85%</a> of the positive cases detected by PCR tests. But the key is that <a href="https://doi.org/10.1093/infdis/jiaa802">published</a> <a href="https://doi.org/10.1128/JCM.00083-21">studies</a> found that they detect over 93% of cases that pose a transmission risk, which is what matters most for getting the pandemic under control. <a href="https://www.ellumehealth.com/products/consumer-products/covid-home-test/">Ellume</a> correctly <a href="https://www.fda.gov/media/144592/download">identifies 95%</a> of all positive cases, and <a href="https://quickvueathome.com/">Quidel QuickVue</a> accurately identifies <a href="https://www.fda.gov/media/146312/download">85%</a>. All three tests correctly identify upwards of 97% of all negative cases, regardless of symptoms.</p>
<figure class="align-center ">
<img alt="A photo of a rapid antigen test kit, available for home use." src="https://images.theconversation.com/files/420363/original/file-20210909-23-ni8knw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/420363/original/file-20210909-23-ni8knw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/420363/original/file-20210909-23-ni8knw.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/420363/original/file-20210909-23-ni8knw.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/420363/original/file-20210909-23-ni8knw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/420363/original/file-20210909-23-ni8knw.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/420363/original/file-20210909-23-ni8knw.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">One of the FDA-approved rapid antigen test kits, which can be used by adults and children age 2 and up.</span>
<span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/QuideltoBringQuickVueAt-HomeOTCCOVID-19TestsToCVSPharmacy/da5b1256e9b05b1af6c4960e08bd9060/photo?Query=home%20antigen%20test&mediaType=photo&sortBy=&dateRange=Anytime&totalCount=18&currentItemNo=16">AP Photo/Business Wire</a></span>
</figcaption>
</figure>
<h2>How should rapid tests be used?</h2>
<p>Rapid antigen testing can be used in three ways to slow transmission. First, people can perform a rapid test when there is a suspected or known COVID-19 exposure. Second, rapid testing can provide an extra precaution before any activity with a higher risk of transmission, such as gatherings or travel. Third, it’s also possible to test on a regular basis – weekly, for instance, if enough tests are available – to catch cases that otherwise might go undetected.</p>
<p>It’s important to have a plan for what to do based on the test results. If you get a positive result, immediately <a href="https://www.cdc.gov/coronavirus/2019-ncov/testing/self-testing.html">take precautions</a> to slow transmission such as self-isolating, letting close contacts know about the test result and reporting the case to health authorities. <a href="https://www.fda.gov/media/147254/download">Less</a> <a href="https://www.fda.gov/media/144592/download">than</a> <a href="https://www.fda.gov/media/146312/download">3%</a> of negative cases receive false positives, but a second rapid test the following day or a PCR test can provide further confirmation if needed.</p>
<p>If you get a negative result from a rapid test, it means you are currently very unlikely to be infectious. A viral load that is too low to be detected by rapid antigen tests is almost surely <a href="https://www.nature.com/articles/d41586-020-02661-2">too low to be transmissible</a>. But it’s important not to let your guard down completely. The tests don’t detect 100% of infectious cases, so it’s possible for a small number to evade detection or for some cases to become infectious within hours after the test. For this reason, it may be a good idea to maintain other precautions. And, if you have symptoms or a known exposure, it’s a good idea to do a follow-up rapid antigen or PCR test just in case the first test was a false negative.</p>
<p>Think of the rapid antigen test as a snapshot in time: A negative test doesn’t necessarily mean you don’t have COVID-19. COVID-19 is <a href="https://www.nytimes.com/interactive/2020/10/02/science/charting-a-coronavirus-infection.html">most transmissible</a> when the viral load peaks, which is estimated to be <a href="https://doi.org/10.1016/S2666-5247(20)30172-5">within a week</a> after infection. Those who are infected but who take a rapid test before or after the viral load peak will get a negative rapid test result – meaning that even though they are infected, they are not currently infectious. One way to reduce the risk of false negatives is with “<a href="https://doi.org/doi:10.1001/jama.2021.5391">serial testing</a>,” where a second rapid test is performed 24-36 hours later to help catch any infectious cases that were missed with the first test.</p>
<h2>Will the new initiatives be enough?</h2>
<p>The <a href="https://www.whitehouse.gov/covidplan/">White House initiatives</a> to increase access to rapid testing are a critical step towards curbing case numbers. But <a href="https://www.whitehouse.gov/covidplan/">one free test</a> per person isn’t sufficient to help people resume normal activities safely. Authorizing additional inexpensive rapid tests through the <a href="https://www.fda.gov/medical-devices/coronavirus-disease-2019-covid-19-emergency-use-authorizations-medical-devices/in-vitro-diagnostics-euas">Food and Drug Administration</a> would further expand supply and reduce prices. </p>
<p>Making the COVID-19 vaccine free and easily accessible <a href="https://doi.org/10.1377/hlthaff.2021.00619">brought cases down</a> <a href="https://www.nytimes.com/2021/04/29/opinion/covid-exponential-decay.html">quickly</a> in the spring of 2021. Putting frequent rapid testing within reach for all <a href="https://www.theatlantic.com/health/archive/2020/08/how-to-test-every-american-for-covid-19-every-day/615217/">could do the same</a> now.</p>
<p><em>This article has been corrected to clarify that less than 3% of negative cases receive false positives.</em></p>
<p>[<em><a href="https://theconversation.com/us/newsletters/science-editors-picks-71/?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=science-corona-important">The Conversation’s most important coronavirus headlines, weekly in a science newsletter</a></em>]</p><img src="https://counter.theconversation.com/content/166869/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Zoë McLaren 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>Making rapid antigen tests for COVID-19 cheaper and more accessible can catch the infectious cases before they spread and help everyone resume normal activities safely.Zoë McLaren, Associate Professor of Public Policy, University of Maryland, Baltimore CountyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1659602021-08-27T12:29:53Z2021-08-27T12:29:53ZVaccines could affect how the coronavirus evolves – but that’s no reason to skip your shot<figure><img src="https://images.theconversation.com/files/417696/original/file-20210824-14-e2lseo.jpg?ixlib=rb-1.1.0&rect=416%2C0%2C7762%2C5199&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Vaccines against COVID-19 are the safest – and fastest – way to prevent the spread of variants.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/doctor-preparing-flu-or-coronavirus-injection-royalty-free-image/1278800490?adppopup=true">Luis Alvarez/ DigitalVision via Getty Images</a></span></figcaption></figure><p><strong>Takeaways</strong></p>
<ul>
<li><p>A 2015 paper on a chicken virus showed vaccines could enable more deadly variants to spread – in chickens.</p></li>
<li><p>But that outcome is rare. Only a minority of human and animal vaccines have affected the evolution of a virus. In most of those cases, evolution didn’t increase the severity of the pathogen.</p></li>
<li><p>The hypothetical possibility that the COVID-19 vaccines could result in more harmful variants is no reason to avoid inoculation. Rather, it shows the need to continue developing vaccines. </p></li>
</ul>
<hr>
<p>In 2015, my collaborators and I published a <a href="https://doi.org/10.1371/journal.pbio.1002198">scientific paper</a> about a chicken virus you have likely never heard of. At the time, it got <a href="https://www.nationalgeographic.com/science/article/leaky-vaccines-enhance-spread-of-deadlier-chicken-viruses">some</a> media attention and has been <a href="https://scholar.google.com/citations?view_op=view_citation&hl=en&user=zFQh3-EAAAAJ&cstart=20&pagesize=80&sortby=pubdate&citation_for_view=zFQh3-EAAAAJ:IaI1MmNe2tcC">cited by other scientists</a> in the years since. </p>
<p>But now, by late-August 2021, the paper <a href="https://journals.plos.org/plosbiology/article/metrics?id=10.1371/journal.pbio.1002198">has been viewed</a> more than 350,000 times – and 70% of those views were in the past three weeks. It has even appeared on a <a href="https://www.youtube.com/watch?v=tiwsv51Il4k&t=52s">YouTube video</a> that’s been seen by 2.8 million people, and counting. </p>
<p>The paper has <a href="https://www.altmetric.com/details/4333559#score">gone viral</a> because <a href="https://www.theepochtimes.com/will-covid-19-vaccines-drive-mutated-variants_3910436.html">some people</a> are using it to stoke paranoia that the COVID-19 vaccines will cause the virus to evolve in the direction of even more severe variants. Doctors have told me that patients are using the paper to justify their decision to not get vaccinated. <a href="https://twitter.com/rourecentenari/status/1428647679463206912">Some</a> <a href="https://climate-science.press/2021/05/18/did-they-forget-to-tell-us-leaky-vaccines-may-trigger-an-arms-race-that-makes-covid-more-dangerous/">pundits</a> are even <a href="https://www.facebook.com/photo.php?fbid=10220062692738356&set=a.10200625587182865&type=3">using it</a> to urge an end to vaccination campaigns in order to prevent the sort of viral evolution we were studying in chickens.</p>
<p>I am receiving emails daily from people worried about getting vaccinated themselves or worried about people rejecting vaccination because of misunderstandings about the paper. </p>
<p>Nothing in our paper remotely justifies an anti-vaccine stance. That misinterpretation – if it causes people to choose not to be vaccinated – will lead to avoidable, and tragic, loss of life. A new study estimates that as of early May 2021, vaccines <a href="https://doi.org/10.1377/hlthaff.2021.00619">had already prevented nearly 140,000 deaths</a> in the U.S. </p>
<p>For over <a href="https://doi.org/10.1038/414751a">20 years</a> <a href="https://scholar.google.com/citations?user=zFQh3-EAAAAJ&hl=en">I’ve been working</a> with <a href="https://doi.org/10.1371/journal.pbio.1001368">collaborators</a> and <a href="https://doi.org/10.1098/rsif.2006.0207">colleagues</a> on how vaccines might affect the evolution of disease-causing organisms like <a href="https://doi.org/10.1111/j.1558-5646.2012.01803.x">viruses</a> and <a href="https://doi.org/10.1371/journal.pbio.1001368">malaria parasites</a>. </p>
<p>Nothing we have discovered or even hypothesized justifies avoiding or withholding vaccines. If anything, <a href="https://theconversation.com/virus-evolution-could-undermine-a-covid-19-vaccine-but-this-can-be-stopped-149234">our work adds to reasons</a> for investigating new vaccine schedules – and for developing second- and third-generation vaccines. </p>
<p>But in the context of the COVID-19 virus, our work does prompt a fair question: Could vaccination cause the emergence of even more harmful variants?</p>
<h2>From chickens to COVID-19</h2>
<p>In the <a href="https://doi.org/10.1371/journal.pbio.1002198">2015 paper</a>, we reported experiments with variants of Marek’s disease virus – the name of the chicken virus we were studying. It is <a href="https://doi.org/10.1038/nrmicro1382">a herpesvirus</a> that causes cancer in domestic chickens. A first-generation vaccine against it <a href="https://doi.org/10.1586/14760584.4.1.77">went into widespread use</a> in poultry in the early 1970s. Today, all commercial chickens and many backyard flocks are vaccinated against Marek’s.</p>
<p>Chickens with Marek’s disease virus became capable of transmitting the virus about 10 days after they get infected. In our lab experiments, we worked with variants of Marek’s disease virus that were so lethal they would kill all unvaccinated birds in 10 days or fewer. So prior to the vaccine, the birds died before they could transmit the lethal variants to other birds. But we found that the first-generation vaccine protected the birds from dying. In other words, the Marek’s-infected chickens lived and were thus able to spread the highly virulent strains to other birds. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/417701/original/file-20210824-26129-1j4qp66.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Penn State biologist Andrew Read holds chicken at poultry farm" src="https://images.theconversation.com/files/417701/original/file-20210824-26129-1j4qp66.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/417701/original/file-20210824-26129-1j4qp66.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/417701/original/file-20210824-26129-1j4qp66.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/417701/original/file-20210824-26129-1j4qp66.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/417701/original/file-20210824-26129-1j4qp66.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/417701/original/file-20210824-26129-1j4qp66.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/417701/original/file-20210824-26129-1j4qp66.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">Penn State biologist Andrew Read (right) and research assistant Chris Cairns studied Marek’s disease virus in poultry chickens.</span>
<span class="attribution"><span class="source">A Chan</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>In the case of COVID-19, it’s becoming increasingly clear that even vaccinated people <a href="https://www.nature.com/articles/d41586-021-02259-2?utm_source=Nature+Briefing&utm_campaign=86c75674aa-briefing-dy-20210820&utm_medium=email&utm_term=0_c9dfd39373-86c75674aa-43257777">can contract and transmit</a> the highly transmissible delta variant. Since viral transmission from vaccinated chickens is what allowed more lethal variants to spread in Marek’s, it’s reasonable to ask whether COVID-19 transmission from vaccinated people could allow more lethal variants to spread.</p>
<h2>Evolution can go in many directions</h2>
<p>As evolutionary ecologist <a href="https://scholar.google.com/citations?user=VkV9_zoAAAAJ&hl=en">David Kennedy</a> and I have <a href="https://theconversation.com/virus-evolution-could-undermine-a-covid-19-vaccine-but-this-can-be-stopped-149234">written about</a> previously, the evolutionary path that the Marek’s disease virus took is one of many that are possible – in rare cases where vaccines drive evolution. </p>
<p>Only a minority of human and animal vaccines <a href="https://doi.org/10.1098/rspb.2016.2562">have influenced</a> pathogen evolution. In nearly all of those cases – which include the hepatitis B virus and bacteria that cause whooping cough and pneumonia – <a href="https://doi.org/10.1073/pnas.1717159115">vaccine efficacy was reduced</a> by new variants. But in contrast to Marek’s, there was no clear evidence that the evolved variants made people sicker.</p>
<p>In nature, we know of course that not all viruses are equally lethal. Biological differences in things like the linkage between disease severity and transmission can cause lethality to increase or decrease. This means that the future of one virus cannot be predicted by simply extrapolating from the past evolution of another. Marek’s and SARS-CoV-2 are very different viruses, with very different vaccines, very different hosts and very different mechanisms by which they sicken and kill. It is impossible to know whether their differences are more important than their similarities.</p>
<p>Evolutionary hypotheticals are important to consider. But up against the hugely beneficial impact of COVID-19 vaccines on reducing <a href="http://dx.doi.org/10.15585/mmwr.mm7034e4">transmission</a> and disease severity – <a href="https://doi.org/10.1056/NEJMoa2108891">even against the delta variant</a> – the possibility of silent spread of more lethal variants among the vaccinated is still no argument against vaccination. </p>
<p>As novel variants of the coronavirus spread in the months and years ahead, it will be vital to work out whether their evolutionary advantage is arising because of reduced disease severity among the vaccinated. Delta, for instance, <a href="https://doi.org/10.1038/d41586-021-02259-2">transmits more effectively</a> from both unvaccinated and vaccinated people than did earlier variants. Extrapolating from our chicken work to argue against vaccination because of the delta variant has no scientific rationale: The delta variant would have become dominant even if everyone refused vaccination.</p>
<h2>But what if?</h2>
<p>If more deadly variants of the coronavirus were to arise, lower vaccination rates would make it easier to identify and contain them because unvaccinated people would suffer more severe infections and higher death rates. But that kind of “solution” would come at considerable cost. In effect, the variants would be found and eliminated by letting people get sick, many of whom would die.</p>
<p>Sacrificing chickens was not the solution the poultry industry adopted for Marek’s disease virus. Instead, more potent vaccines were developed. Those newer vaccines provided <a href="https://doi.org/10.1016/j.prevetmed.2015.04.013">excellent disease control</a>, and no lethal breakthrough variants of Marek’s have emerged in over 20 years. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/417700/original/file-20210824-18817-l8hni4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Chickens in poultry house in Maryland" src="https://images.theconversation.com/files/417700/original/file-20210824-18817-l8hni4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/417700/original/file-20210824-18817-l8hni4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/417700/original/file-20210824-18817-l8hni4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/417700/original/file-20210824-18817-l8hni4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/417700/original/file-20210824-18817-l8hni4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/417700/original/file-20210824-18817-l8hni4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/417700/original/file-20210824-18817-l8hni4.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>
<figcaption>
<span class="caption">Marek’s disease, a cancer-causing herpesvirus in domestic chickens, took a heavy toll on the poultry industry before vaccines were developed against it.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/broiler-chickens-in-poultry-house-royalty-free-image/159235695?adppopup=true">Edwin Remsberg/The Image Bank via Getty Images</a></span>
</figcaption>
</figure>
<p>There are probably ways the available COVID-19 vaccines could be improved in the future to <a href="https://theconversation.com/virus-evolution-could-undermine-a-covid-19-vaccine-but-this-can-be-stopped-149234">better reduce transmission</a>. Booster shots, larger doses or different intervals between doses might help; so too, <a href="https://theconversation.com/a-mix-and-match-approach-to-covid-19-vaccines-could-provide-logistical-and-immunological-benefits-161974">combinations of existing vaccines</a>. Researchers are working hard on these questions. Next-generation vaccines might be even better at blocking transmission. Nasal vaccines, for instance, might effectively curtail transmission because they more specifically target the location of transmissible virus.</p>
<p>As of late August 2021, <a href="https://covid.cdc.gov/covid-data-tracker/#datatracker-home">more than 625,000 Americans have died</a> from a disease that is now largely vaccine-preventable. It is sobering for me to think that some of the next to die might have avoided lifesaving vaccines because people are stoking evolutionary fears extrapolated from our research in chickens. </p>
<p>In the history of human and animal vaccines, there have not been many cases of vaccine-driven evolution. But in every one of them, individuals and populations have <a href="https://doi.org/10.1073/pnas.1717159115">always been better off</a> when vaccinated. At <a href="https://doi.org/10.1016/j.prevetmed.2015.04.013">every point</a> in the 50-year history of vaccination against Marek’s disease, an individual chicken exposed to the virus was healthier if it was vaccinated. Variants may have reduced the benefit of vaccination, but they never eliminated the benefit. Evolution is no reason to avoid vaccination.</p><img src="https://counter.theconversation.com/content/165960/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Andrew Read received funding for the chicken work from Institute of General Medical Sciences, National Institutes of Health (R01GM105244) and the UK Biotechnology and Biological Sciences Research Council as part of the joint NSF-NIH-USDA Ecology and Evolution of Infectious Diseases program. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of this article.</span></em></p>A 2015 paper on chicken virus evolution is being taken out of context and used to fuel fears about COVID-19 vaccines. Its lead author aims to clarify the science in hopes of saving lives.Andrew Read, Professor of Biology, Entomology and Biotechnology, Penn StateLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1636972021-08-10T12:29:00Z2021-08-10T12:29:00ZWhat are COVID-19 variants and how can you stay safe as they spread? A doctor answers 5 questions<figure><img src="https://images.theconversation.com/files/415277/original/file-20210809-19-1b0adqz.jpg?ixlib=rb-1.1.0&rect=60%2C0%2C6720%2C4456&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Vaccination, masking and social distancing are tried and true ways to protect against COVID-19 infection.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/mother-and-daughter-at-the-pediatric-office-royalty-free-image/1266645987">Marko Geber/DigitalVision via Getty Images</a></span></figcaption></figure><p><em>With the delta variant making up <a href="https://covid.cdc.gov/covid-data-tracker/#variant-proportions">over 98% of COVID-19 cases in the U.S. by mid- August 2021</a>, questions arise about how to stay protected against evolving forms of the t virus. Here, pediatrician and infectious disease specialist <a href="https://scholar.google.com/citations?user=vrcymjkAAAAJ&hl=en&oi=sra">Dr. Lilly Cheng Immergluck</a> of Morehouse School of Medicine answers some common questions about variants and what you can do to best protect yourself.</em></p>
<h2>1. What are variants and how do they emerge?</h2>
<p>Viruses <a href="https://dx.doi.org/10.1007%2Fs00018-016-2299-6">mutate over time</a> to adapt to their environment and improve their survival. Over the course of the pandemic, <a href="https://doi.org/10.1038/s41579-020-00459-7">SARS-CoV-2</a>, the novel coronavirus that causes COVID-19, has mutated enough to change both its ability to spread through the population and its ability to infect people.</p>
<p>These new strains are called <a href="https://www.cdc.gov/coronavirus/2019-ncov/variants/variant.html">variants</a>. The U.S. Centers for Disease Control and Prevention currently classifies variants into <a href="https://www.cdc.gov/coronavirus/2019-ncov/variants/variant-info.html">three categories</a>, listed in order of least to most concerning:</p>
<ul>
<li><p>Variant of Interest (VOI): Have features that may reduce your immune system’s ability to prevent infection. For example, you might have heard of VOI eta, iota or kappa.</p></li>
<li><p>Variant of Concern (VOC): Are less responsive to treatments or vaccines and more likely to evade diagnostic detection. They tend to be more transmissible, or contagious, and result in more severe infections. Alpha and delta are VOCs, for instance.</p></li>
<li><p>Variant of High Consequence (VOHC): Are significantly less responsive to existing diagnostic, prevention and treatment options. They also result in more severe infections and hospitalizations. There have not been any VOHCs identified so far.</p></li>
</ul>
<p>The World Health Organization uses <a href="https://www.who.int/en/activities/tracking-SARS-CoV-2-variants/">similar classifications</a>, but their definitions may differ from the CDC’s U.S.-based ones, as variant features and effects may differ by geographic location.</p>
<h2>2. Are variants always more harmful?</h2>
<p>A variant may be more or less dangerous than other strains depending on the mutations in its genetic code. <a href="https://hub.jhu.edu/2021/07/19/andrew-pekosz-delta-variants/">Mutations can affect attributes</a> like how contagious a viral variant is, how it interacts with the immune system or the severity of the symptoms it triggers.</p>
<p>For example, the <a href="https://www.cdc.gov/coronavirus/2019-ncov/variants/variant-info.html">alpha variant</a> is more transmissible than the original form of SARS-CoV-2. Studies show it’s somewhere between <a href="https://doi.org/10.1126/science.abg3055">43% to 90% more contagious</a> than the virus that was most common at the start of the pandemic. Alpha also is more likely to cause severe disease, as indicated by <a href="https://www.cidrap.umn.edu/news-perspective/2021/06/alpha-sars-cov-2-variant-tied-more-severe-outcomes">increased rates of hospitalization and death</a> after infection.</p>
<p>Even more extreme, the delta variant is reported to be <a href="https://www.cdc.gov/coronavirus/2019-ncov/variants/delta-variant.html">more than twice as contagious</a> as previous strains and may cause even more severe disease among those who are unvaccinated. The <a href="https://www.statnews.com/2020/04/14/how-much-of-the-coronavirus-does-it-take-to-make-you-sick/">viral load</a> of those infected with delta – meaning the amount of virus detected from the nasal passages of an infected person – is also reported to be <a href="https://doi.org/10.1038/d41586-021-01986-w">over 1,000 times higher</a> than in those infected with the original form of SARS-CoV-2. Recent evidence also suggests that both <a href="https://www.cdc.gov/media/releases/2021/s0730-mmwr-covid-19.html">unvaccinated and vaccinated people carry similar viral loads</a>, further contributing to the especially contagious nature of this variant.</p>
<h2>3. Which variants are most common in the US?</h2>
<p>Over the course of a few months, the delta variant has become the predominant strain in the U.S., accounting for <a href="https://covid.cdc.gov/covid-data-tracker/#variant-proportions">the vast majority of COVID-19 cases at the end of July 2021</a>.</p>
<p><iframe id="T19uC" class="tc-infographic-datawrapper" src="https://datawrapper.dwcdn.net/T19uC/2/" height="400px" width="100%" style="border: none" frameborder="0"></iframe></p>
<p>But there are regional variations across the country. As of July 31, the CDC estimated that the alpha variant represented over 3% of cases identified in a region of eight states that includes Georgia, Florida and Tennessee, compared with less than 1% in the region that includes Iowa, Kansas, Missouri and Nebraska. Since then, the delta variant has dominated alpha and other variants in these regions. The <a href="https://covid.cdc.gov/covid-data-tracker/#variant-proportions">CDC tracks variants</a> in cooperation with state health departments and other public health agencies. <a href="https://www.cdc.gov/coronavirus/2019-ncov/variants/cdc-role-surveillance.html">COVID-19 infection samples</a> from across the country are genetically sequenced each week to identify existing and new variants.</p>
<p>And new variants will likely continue to <a href="https://www.vox.com/science-and-health/22586816/next-coronavirus-variant-delta-covid-19">appear as the virus evolves</a>. <a href="https://www.reuters.com/business/healthcare-pharmaceuticals/what-is-delta-variant-coronavirus-with-k417n-mutation-2021-06-23/">Delta plus</a>, for instance, is a sub-lineage of delta. The effects of this subvariant are yet to be determined.</p>
<h2>4. How are vaccines holding up against variants?</h2>
<p>Researchers are working to figure out how effective the <a href="https://www.cdc.gov/coronavirus/2019-ncov/vaccines/keythingstoknow.html">three COVID-19 vaccines currently authorized for emergency use</a> in the U.S. are at preventing infection from variants in “real-world” conditions where variant distribution and frequency constantly change. Several preliminary studies that have not yet been peer-reviewed suggest that these vaccines are <a href="https://www.who.int/publications/m/item/weekly-epidemiological-update-on-covid-19---20-july-2021">still effective in preventing COVID-19-related serious infections and death</a>. </p>
<p>No vaccine is perfect, however, and <a href="https://www.cdc.gov/vaccines/covid-19/health-departments/breakthrough-cases.html">breakthrough COVID-19 infections</a> are possible in those who are vaccinated. <a href="https://www.cdc.gov/coronavirus/2019-ncov/need-extra-precautions/people-with-medical-conditions.html">Older adults and those with immunocompromising conditions</a> may be at increased risk to have these breakthrough infections.</p>
<figure class="align-center ">
<img alt="People getting vaccinated at a clinic." src="https://images.theconversation.com/files/415063/original/file-20210806-21-1abdroh.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C4000%2C2449&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/415063/original/file-20210806-21-1abdroh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=368&fit=crop&dpr=1 600w, https://images.theconversation.com/files/415063/original/file-20210806-21-1abdroh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=368&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/415063/original/file-20210806-21-1abdroh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=368&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/415063/original/file-20210806-21-1abdroh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=462&fit=crop&dpr=1 754w, https://images.theconversation.com/files/415063/original/file-20210806-21-1abdroh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=462&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/415063/original/file-20210806-21-1abdroh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=462&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Vaccines are not foolproof, but they significantly reduce the risk of severe infection.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/people-get-vaccinated-at-a-vaccination-clinic-at-save-max-news-photo/1233919858">Xinhua News Agency/Getty Images</a></span>
</figcaption>
</figure>
<p>Thankfully, fully vaccinated individuals generally experience <a href="https://www.cdc.gov/coronavirus/2019-ncov/vaccines/effectiveness/why-measure-effectiveness/breakthrough-cases.html">milder COVID-19 infections</a>. For example, a <a href="https://doi.org/10.1056/NEJMoa2108891">study analyzing COVID-19 cases in England</a> estimated that two doses of the Pfizer BioNTech vaccine are 93.7% effective in preventing symptomatic disease from the alpha variant and 88% effective from delta. A different <a href="https://doi.org/10.1101/2021.06.28.21259420">study in Ontario, Canada, that is not yet peer-reviewed</a> reported that the Moderna vaccine is 92% effective in preventing symptomatic disease from alpha. </p>
<h2>5. How can I stay safe?</h2>
<p>How cautious you should be <a href="https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-sick/about-face-coverings.html">depends on a number of individual and external factors</a>. </p>
<p>One factor is whether you’re <a href="https://www.cdc.gov/coronavirus/2019-ncov/vaccines/fully-vaccinated.html">fully vaccinated</a>. <a href="https://theconversation.com/us-is-split-between-the-vaccinated-and-unvaccinated-and-deaths-and-hospitalizations-reflect-this-divide-164460">Nearly all - 99.5% - of COVID-19 deaths</a> in the U.S. over the past few months were among unvaccinated people.</p>
<p>The <a href="https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-sick/about-face-coverings.html">most recent CDC guidelines</a> recommend that everyone wear a mask in areas of <a href="https://covid.cdc.gov/covid-data-tracker/#county-view">substantial or high transmission</a>, regardless of whether or not <a href="https://www.cdc.gov/coronavirus/2019-ncov/vaccines/fully-vaccinated.html">they’re vaccinated</a>. More caution should especially be taken if you <a href="https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-sick/about-face-coverings.html">aren’t fully vaccinated</a> or have a <a href="https://www.cdc.gov/coronavirus/2019-ncov/vaccines/fully-vaccinated-guidance.html">weakened immune system</a>. </p>
<p>[<em>Understand new developments in science, health and technology, each week.</em> <a href="https://theconversation.com/us/newsletters/science-editors-picks-71/?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=science-understand">Subscribe to The Conversation’s science newsletter</a>.]</p>
<p>Another factor to consider is the level of community transmission and the proportion of unvaccinated people in your local community. For example, someone who lives in an area that is below the <a href="https://covid.cdc.gov/covid-data-tracker/#county-view">national average for COVID-19 vaccinations</a> may have a higher chance of encountering someone who is unvaccinated – and so more likely to spread the coronavirus – than someone in an area with higher vaccination rates.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/9Tv2BVN_WTk?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Properly wearing a mask can help protect you and others from COVID-19 infection.</span></figcaption>
</figure>
<p>Finally, there are still a significant number of people who are at high risk of COVID-19, including children. As of Aug. 18, 2021, <a href="https://data.cdc.gov/Vaccinations/COVID-19-Vaccination-and-Case-Trends-by-Age-Group-/gxj9-t96f">only 32.6% of children ages 12 to 15</a>, and 43% of those ages 16 and 17, had been fully vaccinated. The American Academy of Pediatrics and the Children’s Hospital Association note that <a href="https://services.aap.org/en/pages/2019-novel-coronavirus-covid-19-infections/children-and-covid-19-state-level-data-report/">4,413,547 total child COVID-19 cases</a> had been reported as of Aug. 12. Children make up 14.4% of reported COVID-19 cases. If your child is unvaccinated, the best way you can protect them and other unvaccinated members of your household is to <a href="https://www.cdc.gov/coronavirus/2019-ncov/your-health/about-covid-19/caring-for-children/families.html">get yourself vaccinated and have everyone wear a mask in indoor public spaces</a>.</p>
<p>Guidelines provided by public health agencies are simply that – general guidelines. They are not tailored to be prescriptive for each individual and their personal risk assessments. </p>
<p>Vaccines remain the best protection against every strain of the novel coronavirus. But <a href="https://doi.org/10.1016/S0140-6736(20)31142-9">masking, social distancing and avoiding crowds and poorly ventilated indoor spaces</a> add extra layers of protection against <a href="https://theconversation.com/what-is-a-breakthrough-infection-6-questions-answered-about-catching-covid-19-after-vaccination-164909">breakthrough infections</a> and lower your risk of <a href="https://theconversation.com/can-people-vaccinated-against-covid-19-still-spread-the-coronavirus-161166">inadvertently spreading the virus</a>.</p>
<p><em>Article updated to reflect data current as of Aug. 19, 2021.</em></p><img src="https://counter.theconversation.com/content/163697/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Lilly Cheng Immergluck receives funding from the National Institutes of Health (NIH) and Pediatric Emergency Medicine Associates, LLC. </span></em></p>New variants of the COVID-19 virus may be more contagious and cause more severe disease than the original. A pediatrician and infectious disease specialist explains why.Lilly Cheng Immergluck, Professor of Microbiology, Biochemistry and Immunology, Morehouse School of MedicineLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1649092021-07-28T12:26:20Z2021-07-28T12:26:20ZWhat is a breakthrough infection? 6 questions answered about catching COVID-19 after vaccination<figure><img src="https://images.theconversation.com/files/413415/original/file-20210727-27-188r9dh.jpg?ixlib=rb-1.1.0&rect=81%2C0%2C3595%2C2855&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Vaccines don't ward off every single infection but they do massively lower the risk.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/mobile-covid-19-testing-van-queens-new-york-news-photo/1323834512">Education Images/Universal Images Group via Getty Images</a></span></figcaption></figure><p>If you’ve been fully vaccinated against COVID-19, maybe you figured you no longer need to worry about contracting the coronavirus. But along with the <a href="https://covid19.who.int/">rising number of new COVID-19 cases globally</a> and growing concern about <a href="https://covariants.org/variants/21A.Delta">highly transmissible strains like the delta variant</a> come reports of fully vaccinated people testing positive for COVID-19.</p>
<p>Members of the <a href="https://nymag.com/intelligencer/2021/05/what-really-happened-with-that-weird-yankees-covid-outbreak.html">New York Yankees</a>, U.S. Olympic gymnast <a href="https://www.nbcnews.com/news/olympics/member-u-s-women-s-gymnastics-team-tests-positive-covid-n1274334">Kara Eaker</a> and U.K. health secretary <a href="https://www.bbc.com/news/uk-57874744">Sajid Javid</a> are some of those diagnosed with what is called a “breakthrough infection.”</p>
<p>As scary as the term may sound, the bottom line is that the existing COVID-19 vaccines are still <a href="https://doi.org/10.1056/NEJMoa2108891">very good at preventing symptomatic infections</a>, and breakthrough infections happen very rarely. But just how common and how dangerous are they? Here’s a guide to what you need to know.</p>
<h2>What is ‘breakthrough infection?’</h2>
<p>No vaccine is 100% effective. Dr. Jonas Salk’s polio vaccine was <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1622939/pdf/amjphnation00353-0017.pdf">80%-90% effective</a> in preventing paralytic disease. Even for the gold standard measles vaccine, the efficacy was <a href="https://doi.org/10.1017/S0950268800058441">94% among a highly vaccinated population</a> during large outbreaks.</p>
<p>Comparably, clinical trials found the mRNA vaccines from <a href="https://doi.org/10.1056/NEJMoa2034577">Pfizer</a> and <a href="https://doi.org/10.1056/NEJMoa2035389">Moderna</a> were 94%–95% effective at preventing symptomatic COVID-19 – <a href="https://www.fda.gov/media/139638/download">much more protective than initially hoped</a>.</p>
<p>A quick reminder: A vaccine efficacy of 95% does not mean that the shot protects 95% of people while the other 5% will contract the virus. Vaccine efficacy is a measure of relative risk – you need to compare a group of vaccinated people to a group of unvaccinated people under the same exposure conditions. So consider a three-month study period during which 100 out of 10,000 unvaccinated people got COVID-19. <a href="https://doi.org/10.1016/S1473-3099(21)00075-X">You’d expect five vaccinated people</a> to get sick during that same time. That’s 5% of the 100 unvaccinated people who fell ill, not 5% of the whole group of 10,000.</p>
<p>When people get infected after vaccination, scientists call these cases “breakthrough” infections because the virus <a href="https://doi.org/10.1172/JCI151186">broke through the protective barrier the vaccine provides</a>.</p>
<h2>How common is COVID-19 infection in the fully vaccinated?</h2>
<p>Breakthrough infections are <a href="https://www.gavi.org/vaccineswork/what-difference-between-efficacy-and-effectiveness">a little more frequent than previously expected</a> and are probably increasing because of <a href="https://covid.cdc.gov/covid-data-tracker/#variant-proportions">growing dominance of the delta variant</a>. But infections in vaccinated people are still very rare and usually cause <a href="https://doi.org/10.1056/NEJMoa2105000">mild or no symptoms</a>.</p>
<p>For instance, <a href="https://www.rockefellerfoundation.org/blog/the-u-s-can-lead-the-way-in-vaccine-breakthrough-reporting-will-it-squander-this-opportunity/">46 U.S. states and territories</a> voluntarily reported <a href="https://www.cdc.gov/mmwr/volumes/70/wr/mm7021e3.htm">10,262 breakthrough infections</a> to the U.S. Centers for Disease Control and Prevention between Jan. 1 and April 30, 2021. By comparison, there <a href="https://covid.cdc.gov/covid-data-tracker/#trends_dailytrendscases">were 11.8 million</a> COVID-19 diagnoses in total during the same period.</p>
<p>Beginning May 1, 2021, the CDC stopped monitoring vaccine breakthrough cases unless they resulted in hospitalization or death. Through July 19, 2021, there were <a href="https://www.cdc.gov/vaccines/covid-19/health-departments/breakthrough-cases.html">5,914 patients with COVID-19 vaccine breakthrough infections</a> who were hospitalized or died in the U.S., out of more than 159 million people fully vaccinated nationwide.</p>
<p>One study between Dec. 15, 2020, and March 31, 2021, that included 258,716 veterans who received two doses of the Pfizer or Moderna vaccine, counted <a href="https://doi.org/10.1016/j.jinf.2021.05.021">410 who got breakthrough infections</a> – that’s 0.16% of the total. Similarly, a study in New York noted <a href="https://doi.org/10.1101/2021.07.05.21259547">86 cases of COVID-19 breakthrough infections</a> between Feb. 1 and April 30, 2021, among 126,367 people who were fully vaccinated, mostly with mRNA vaccines. This accounts for 1.2% of total COVID-19 cases and 0.07% of the fully vaccinated population.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/413418/original/file-20210727-17-swnq10.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="woman with lowered mask swabs her own nose" src="https://images.theconversation.com/files/413418/original/file-20210727-17-swnq10.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/413418/original/file-20210727-17-swnq10.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=434&fit=crop&dpr=1 600w, https://images.theconversation.com/files/413418/original/file-20210727-17-swnq10.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=434&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/413418/original/file-20210727-17-swnq10.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=434&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/413418/original/file-20210727-17-swnq10.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=545&fit=crop&dpr=1 754w, https://images.theconversation.com/files/413418/original/file-20210727-17-swnq10.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=545&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/413418/original/file-20210727-17-swnq10.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=545&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Even if you’re fully vaccinated, you should get tested if you have symptoms.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/dolores-velasquez-who-volunteers-at-the-pico-union-project-news-photo/1234183465">Al Seib/Los Angeles Times via Getty Images</a></span>
</figcaption>
</figure>
<h2>How serious is a COVID-19 breakthrough infection?</h2>
<p>The CDC <a href="https://www.cdc.gov/vaccines/covid-19/health-departments/breakthrough-cases.html">defines a vaccine breakthrough infection</a> as one in which a nasal swab can detect the SARS-CoV-2 RNA or protein more than 14 days after a person has completed the full recommended doses of an FDA-authorized COVID-19 vaccine.</p>
<p>Note that a breakthrough infection doesn’t necessarily mean the person feels sick – and in fact, <a href="https://www.cdc.gov/mmwr/volumes/70/wr/mm7021e3.htm">27% of breakthrough cases reported to the CDC were asymptomatic</a>. Only 10% of the breakthrough-infected people were known to be hospitalized (some for reasons other than COVID-19), and 2% died. For comparison, during the spring of 2020 when vaccines were not yet available, over <a href="https://ourworldindata.org/explorers/coronavirus-data-explorer?zoomToSelection=true&time=2020-03-14..latest&pickerSort=asc&pickerMetric=location&hideControls=true&Metric=Case+fatality+rate&Interval=Cumulative&Relative+to+Population=false&Align+outbreaks=true&country=%7EUSA">6% of confirmed infections were fatal</a>.</p>
<p>In <a href="https://doi.org/10.1093/cid/ciab543">a study at U.S. military treatment facilities</a>, none of the breakthrough infections led to hospitalization. In another study, after just <a href="https://doi.org/10.1038/s41591-021-01316-7">one dose of Pfizer vaccine</a> the vaccinated people who tested positive for COVID-19 had a quarter less virus in their bodies than those who were unvaccinated and tested positive.</p>
<h2>What makes a breakthrough infection more likely?</h2>
<p>Nationwide, on average more than 5% of COVID-19 tests are coming back positive; in <a href="https://coronavirus.jhu.edu/testing/tracker/map/percent-positive">Alabama, Mississippi and Oklahoma, the positivity rate is above 30%</a>. Lots of coronavirus circulating in a community pushes the chance of breakthrough infections higher.</p>
<p>The likelihood is greater in situations of close contact, such as in a <a href="https://wwwnc.cdc.gov/eid/article/27/10/21-1427_article#suggestedcitation">cramped working space</a>, party, restaurant or stadium. Breakthrough infections are also <a href="https://doi.org/10.1093/cid/ciab543">more likely among health care workers</a> who are <a href="https://doi.org/10.1101/2021.06.07.21258447">in frequent contact with infected patients</a>.</p>
<p>For reasons that are unclear, <a href="https://www.cdc.gov/mmwr/volumes/70/wr/mm7021e3.htm">nationwide CDC data</a> found that women account for 63% of breakthrough infections. Some smaller studies <a href="https://doi.org/10.1101/2021.06.21.21258990">identified women as the majority</a> of breakthrough cases as well.</p>
<p>Vaccines trigger a <a href="https://doi.org/10.1038/s41586-021-03739-1">less robust immune response among older people</a>, and the chances of a breakthrough infection get <a href="https://doi.org/10.1016/j.jinf.2021.05.021">higher with increasing age</a>. Among the breakthrough cases tracked by the CDC, <a href="https://www.cdc.gov/vaccines/covid-19/health-departments/breakthrough-cases.html">75% occurred in patients age 65 and older</a>.</p>
<p><a href="https://doi.org/10.1016/j.cmi.2021.06.036">Being immunocompromised</a> or having underlying conditions such as high blood pressure, diabetes, heart disease, chronic kidney and lung diseases <a href="https://doi.org/10.1016/j.ccell.2021.07.012">and cancer</a> <a href="https://doi.org/10.1016/j.cmi.2021.06.036">increase the chances of breakthrough infections</a> and can lead to severe COVID-19. For example, fully vaccinated organ transplant recipients were <a href="https://doi.org/10.1097/TP.0000000000003907">82 times more likely to get a breakthrough infection</a> and had a <a href="https://doi.org/10.1097/TP.0000000000003907">485-fold higher risk of hospitalization and death</a> after a breakthrough infection compared with the vaccinated general population in one study. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/413419/original/file-20210727-19-o2jkyf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="people at a mobile vaccination site" src="https://images.theconversation.com/files/413419/original/file-20210727-19-o2jkyf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/413419/original/file-20210727-19-o2jkyf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=343&fit=crop&dpr=1 600w, https://images.theconversation.com/files/413419/original/file-20210727-19-o2jkyf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=343&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/413419/original/file-20210727-19-o2jkyf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=343&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/413419/original/file-20210727-19-o2jkyf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=431&fit=crop&dpr=1 754w, https://images.theconversation.com/files/413419/original/file-20210727-19-o2jkyf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=431&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/413419/original/file-20210727-19-o2jkyf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=431&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Vaccination is still your best bet against emerging coronavirus variants.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/people-arrive-for-shots-at-a-mobile-covid-19-vaccination-news-photo/1234101872">Paul Hennessy/SOPA Images/LightRocket via Getty Images</a></span>
</figcaption>
</figure>
<h2>How do variants like delta change things?</h2>
<p>Researchers developed today’s vaccines to ward off earlier strains of the SARS-CoV-2 virus. Since then <a href="https://covariants.org/variants/21A.Delta">new variants have emerged</a>, many of which are <a href="https://doi.org/10.1038/s41586-021-03777-9">better at dodging the antibodies</a> produced by the currently authorized vaccines. While existing vaccines are still very effective against these variants for preventing hospitalization, they are less effective than against previous variants. </p>
<p><a href="https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1005085/Vaccine_surveillance_report_-_week_29.pdf">Two doses of the mRNA vaccines were only 79% effective</a> at preventing symptomatic disease with delta, compared with 89% effective in the case of the earlier alpha variant, according to Public Health England. A single dose was <a href="https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1005085/Vaccine_surveillance_report_-_week_29.pdf">only 35%</a> protective against delta. </p>
<p>About <a href="https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1005517/Technical_Briefing_19.pdf">12.5% of the 229,218 delta variant cases</a> across England through July 19 were among fully vaccinated people.</p>
<p>Israel, with high vaccination rates, has reported that full vaccination with the Pfizer vaccine might be only <a href="https://www.gov.il/BlobFolder/reports/vaccine-efficacy-safety-follow-up-committee/he/files_publications_corona_two-dose-vaccination-data.pdf">39%-40.5% effective at preventing delta variant infections</a> of any severity, down from <a href="https://www.reuters.com/business/healthcare-pharmaceuticals/pfizer-says-covid-vaccine-highly-effective-against-delta-variant-2021-06-24/">early estimates of 90%</a>. Israel’s findings suggest that within six months, COVID-19 vaccines’ efficacy at preventing infection and symptomatic disease declines. The good news, though, is that the vaccine is still highly effective at protecting against <a href="https://www.gov.il/BlobFolder/reports/vaccine-efficacy-safety-follow-up-committee/he/files_publications_corona_two-dose-vaccination-data.pdf">hospitalization (88%)</a> and <a href="https://www.gov.il/BlobFolder/reports/vaccine-efficacy-safety-follow-up-committee/he/files_publications_corona_two-dose-vaccination-data.pdf">severe illness (91.4%)</a> caused by the now-dominant delta variant.</p>
<h2>So how well are vaccines holding up?</h2>
<p>As of the end of July 2021, <a href="https://covid.cdc.gov/covid-data-tracker/#vaccinations">49.1% of the U.S. population</a>, or just over 163 million people, are fully vaccinated. Nearly 90% of Americans over the age of 65 have received at least one dose of a vaccine.</p>
<p>Scientists’ models suggest that vaccination may have <a href="https://doi.org/10.26099/wm2j-mz32">saved approximately 279,000 lives</a> in the U.S. and prevented up to 1.25 million hospitalizations by the end of June 2021. Similarly, in England about <a href="https://www.gov.uk/government/news/covid-19-vaccine-surveillance-report-published">30,300 deaths, 46,300 hospitalizations and 8.15 million infections</a> may have been prevented by COVID-19 vaccines. In Israel, the high vaccination rate is thought to have caused a <a href="https://doi.org/10.1038/s41591-021-01337-2">77% drop in cases and a 68% drop in hospitalizations</a> from that nation’s pandemic peak.</p>
<p>Across the U.S., only 150 out of more than 18,000 deaths due to COVID-19 in May were of people who had been fully vaccinated. That means nearly all COVID-19 deaths in U.S. are <a href="https://apnews.com/article/coronavirus-pandemic-health-941fcf43d9731c76c16e7354f5d5e187">among those who remain unvaccinated</a>.</p>
<p>The U.S. is becoming “<a href="https://www.cnn.com/videos/health/2021/06/30/anthony-fauci-covid-vaccination-rate-delta-variant-sot-vpx-dlt.cnn">almost like two Americas</a>,” as Anthony Fauci put it, divided between the vaccinated and the unvaccinated. Those who have not been fully vaccinated against COVID-19 remain at risk from the coronavirus that has so far killed more than 600,000 people in the U.S.</p>
<p>[<em>Get the best of The Conversation, every weekend.</em> <a href="https://theconversation.com/us/newsletters/weekly-highlights-61?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=weeklybest">Sign up for our weekly newsletter</a>.]</p><img src="https://counter.theconversation.com/content/164909/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Sanjay Mishra receives funding from the National Cancer Institute, through his employer. Sanjay Mishra is a member of the American Association for Cancer Research (AACR). He also writes for National Geographic. </span></em></p>Vaccines can’t provide 100% protection, so it’s not a failure or surprise when some vaccinated people get sick with COVID-19. The good news is their cases are much less likely to be severe or fatal.Sanjay Mishra, Project Coordinator & Staff Scientist, Vanderbilt University Medical Center, Vanderbilt UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1641642021-07-09T05:49:03Z2021-07-09T05:49:03ZShould I have my AstraZeneca booster shot at 8 weeks rather than 12? Here’s the evidence so you can decide<figure><img src="https://images.theconversation.com/files/410496/original/file-20210709-19-eimpsf.jpg?ixlib=rb-1.1.0&rect=1%2C0%2C997%2C519&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/close-top-view-on-white-calendar-1861762180">from www.shutterstock.com</a></span></figcaption></figure><p>Prime Minister Scott Morrison appeared to have made a “captain’s call” yesterday by <a href="https://www.abc.net.au/news/2021-07-08/scott-morrison-covid-vaccine-nsw-outbreak/100277466">encouraging people</a> in New South Wales outbreak areas to have their AstraZeneca booster closer to eight weeks after their initial shot rather than wait for the generally recommended 12 weeks.</p>
<blockquote>
<p>We would be encouraging the eight to 12-week second dose be done at the earlier part of that period […]. That is consistent with medical advice […] and given the risks to people from the outbreak in that area we believe it is important they get that second dose of AstraZeneca as soon as possible.</p>
</blockquote>
<p>The official health advice from ATAGI, the Australian Technical Advisory Group on Immunisation, remains most people have their booster shot <a href="https://www.health.gov.au/sites/default/files/documents/2021/06/covid-19-vaccination-atagi-clinical-guidance-on-covid-19-vaccine-in-australia-in-2021_1.pdf">at 12 weeks</a> for optimal COVID protection, but under certain circumstances that can go down to four weeks. Those circumstances include imminent travel or if there’s a risk of COVID-19 exposure.</p>
<p>ATAGI’s concern, and that of <a href="https://www.smh.com.au/national/vaccine-experts-warn-against-reducing-time-between-astrazeneca-doses-20210707-p587n6.html">some other vaccine experts</a>, is if you have your booster shot earlier than 12 weeks, your body won’t develop enough immunity to reliably protect you from serious disease.</p>
<p>Confused? Here is what we know so far.</p>
<h2>What’s the official advice?</h2>
<p>The evidence underpinning the <a href="https://www.health.gov.au/sites/default/files/documents/2021/06/covid-19-vaccination-atagi-clinical-guidance-on-covid-19-vaccine-in-australia-in-2021_1.pdf">recommended 12 week gap</a> between the first and second AstraZeneca shots comes from a study published in <a href="https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(21)00432-3/fulltext">the Lancet</a>. </p>
<p>The study found leaving less than six weeks between the initial shot and the booster gave 55.1% efficacy (protection from symptomatic disease). Leaving 6-8 weeks between shots increased efficacy to 59.9%, and waiting 9-11 weeks, efficacy was 63.7%. However, if the gap was 12 weeks or longer efficacy jumped to 81.3%.</p>
<p>So to get the best protection from the AstraZeneca vaccine, you need at least 12 weeks between your first and second shot.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/408593/original/file-20210628-27-1lcjcwa.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/408593/original/file-20210628-27-1lcjcwa.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=509&fit=crop&dpr=1 600w, https://images.theconversation.com/files/408593/original/file-20210628-27-1lcjcwa.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=509&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/408593/original/file-20210628-27-1lcjcwa.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=509&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/408593/original/file-20210628-27-1lcjcwa.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=640&fit=crop&dpr=1 754w, https://images.theconversation.com/files/408593/original/file-20210628-27-1lcjcwa.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=640&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/408593/original/file-20210628-27-1lcjcwa.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=640&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
<span class="attribution"><a class="source" href="https://www.sciencedirect.com/science/article/pii/B978032335761600002X">The Conversation (adapted from Vaccine Immunology, Plotkin's Vaccines [Seventh Edition] 2018)</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Now we find ourselves with an active outbreak of the highly transmissible Delta variant of SARS-CoV-2 in Sydney. So we need to ask ourselves whether aiming for the highest level of protection is best, or whether we need to aim for a reasonable level of immunity as quickly as possible.</p>
<p>The Lancet paper didn’t include data on the Delta variant as it wasn’t widely circulating at the time, but this is fast becoming the <a href="https://www.euronews.com/2021/06/23/delta-variant-to-account-for-90-of-new-covid-19-cases-in-europe-by-late-august-warns-eu-ag">dominant variant globally</a>.</p>
<p>Yet we do know <a href="https://theconversation.com/should-i-get-my-second-astrazeneca-dose-yes-it-almost-doubles-your-protection-against-delta-163259">two doses</a> of the AstraZeneca vaccine protects against serious COVID-19 after infection with the Delta variant, whereas <a href="https://www.nature.com/articles/s41586-021-03777-9">one dose doesn’t</a>.</p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/should-i-get-my-second-astrazeneca-dose-yes-it-almost-doubles-your-protection-against-delta-163259">Should I get my second AstraZeneca dose? Yes, it almost doubles your protection against Delta</a>
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<h2>What’s the evidence for 8 weeks to protect against Delta?</h2>
<p>Morrison’s call for some people to have their AstraZeneca booster shot from around eight weeks hasn’t come completely out of the blue. It’s an approach <a href="https://www.health-ni.gov.uk/news/introduction-shorter-interval-between-vaccine-doses">the UK has been using</a> to get ahead of the infectious Delta variant, the same variant circulating in NSW.</p>
<p>We know leaving less time between AstraZeneca shots generally reduces vaccine efficacy. But what about that in the context of the Delta variant? This is where things get a bit tricky if we actually want to put a figure on precisely how much vaccine efficacy reduces.</p>
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<p>A study published in <a href="https://www.nature.com/articles/s41586-021-03777-9">Nature</a> reported a single dose of AstraZeneca vaccine induced essentially no Delta virus-neutralising antibodies. </p>
<p>However, two doses induced a neutralising antibody response in 95% of people, albeit at a significantly lower level than with the Alpha variant (which originated in the UK).</p>
<p>Still, neutralising antibodies against Delta were there in the vast majority of people after two shots, antibodies that could mean the difference between a mild illness and hospitalisation with severe disease. </p>
<p>There are some limitations with this study. First, it did not directly assess vaccine efficacy (you need to conduct a clinical trial for that). Second, it used a range of intervals between first and second shots, so we cannot definitively say the precise protection from the Delta strain at eight weeks versus 12 weeks. </p>
<p>However, assessing the capacity of vaccinated peoples’ antibodies to neutralise viruses in the lab is a good indicator of the quality of vaccine-induced protection — and this study really highlighted the need for a booster shot for protection against the Delta variant. </p>
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<strong>
Read more:
<a href="https://theconversation.com/the-symptoms-of-the-delta-variant-appear-to-differ-from-traditional-covid-symptoms-heres-what-to-look-out-for-163487">The symptoms of the Delta variant appear to differ from traditional COVID symptoms. Here's what to look out for</a>
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<p>So with infection numbers in Sydney looking more ominous by the day, coupled with the knowledge one vaccine dose is all but useless against the Delta virus, it is clear getting two doses into the arms of as many people as possible as quickly as possible, is the strategy. </p>
<p>Two doses, even at eight weeks apart, while not providing the highest possible level of protection, will still protect many from severe disease. </p>
<h2>What else do I need to think about?</h2>
<p>A drop in immunity is not the only thing to consider when weighing up the pros and cons of having your AstraZeneca booster shot early.</p>
<p>We’ve just heard more Pfizer shots are on their way <a href="https://www.abc.net.au/news/2021-07-09/australia-to-get-pfizer-covid19-vaccine-supply-august/100279944">sooner than expected</a>. If a Pfizer booster shot is made available to people who have already had two shots of AstraZeneca (and this is a big if), this could be a game changer.</p>
<p>In this case — and remember this mix-and-match approach has not been officially sanctioned — it might not matter too much if an early second dose of the AstraZeneca vaccine gives you sub-optimal immunity. The Pfizer booster would lift your immunity instead. </p>
<p>However, it remains to be seen whether such a major policy shift would happen in time to protect people currently in lockdown in NSW.</p>
<h2>Take-home message</h2>
<p>The Delta variant is <a href="https://theconversation.com/why-is-delta-such-a-worry-its-more-infectious-probably-causes-more-severe-disease-and-challenges-our-vaccines-163579">highly transmissible</a>. So weeks do matter, and with Australia still heavily reliant on the AstraZeneca vaccine, for now it does makes sense to reduce the time between the first and second jab. </p>
<p>This is clearly preferable to remaining unprotected for an extra month, particularly if you are at higher risk of infection and/or severe disease.</p><img src="https://counter.theconversation.com/content/164164/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Nathan Bartlett 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>Weeks do matter when it comes to the Delta strain. With Australia still heavily reliant on the AstraZeneca vaccine, for now it makes sense to reduce the time between the first and second jab.Nathan Bartlett, Associate Professor, School of Biomedical Sciences and Pharmacy, University of NewcastleLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1629262021-07-01T19:53:30Z2021-07-01T19:53:30ZHow well do COVID vaccines work in the real world?<figure><img src="https://images.theconversation.com/files/409222/original/file-20210701-21240-j7md96.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C998%2C597&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/coronavirus-faces-collage-composition-different-multi-1774439057">www.shutterstock.com</a></span></figcaption></figure><p>Many Australians will be <a href="https://www.theguardian.com/australia-news/2021/jul/01/confused-about-whether-you-can-get-an-astrazeneca-vaccine-heres-what-you-need-to-know">weighing up</a> whether to be vaccinated with the AstraZeneca vaccine, which is widely available, or to wait for Pfizer later in the year. </p>
<p>There are many factors to consider. One is how well these COVID-19 vaccines work in the “real world” of those getting vaccines now.</p>
<p>Real-world data data can tell us how well vaccines protect against currently circulating variants — including the Delta variant, which is dominant in the UK and the subject of lockdowns in Australia. Though less reliable than clinical trials, real-world data can tell us how well vaccines work in some parts of the population excluded from clinical trials. They can also tell us whether we can effectively mix vaccines and what the main side-effects are, almost in real time.</p>
<p>You might be surprised by the results.</p>
<h2>Where did these data come from?</h2>
<p>Results of the crucial randomised clinical trials, which led to COVID vaccines being approved around the world, led to extraordinary media coverage. The vaccines have since become household names. But those trials were only the beginning.</p>
<p>Data collected during health-care delivery including medical consultations, hospital admissions, vaccine registers, laboratory tests and death records give us more, and different information about the vaccines.</p>
<p>These are data about millions of individual people, which are de-identified before analysis. Analysed properly, they tell us how well vaccines work, and their side-effects, in the real world.</p>
<h2>How well do COVID vaccines protect you from serious disease?</h2>
<p>The most important finding from analysing these data is vaccines from AstraZeneca, Pfizer and Moderna appear equivalent in reducing your chance of serious illness from COVID-19. As we show <a href="https://www.mja.com.au/journal/2021/effectiveness-covid-19-vaccines-findings-real-world-studies">in our recent review</a>, they do this by more than 80%.</p>
<p>These results extend the findings of the randomised trials by showing all ages benefit from the vaccines, and people with underlying chronic diseases experience reduced, but still worthwhile, protection from serious illness.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/which-covid-vaccine-is-best-heres-why-thats-really-hard-to-answer-161185">Which COVID vaccine is best? Here's why that's really hard to answer</a>
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<h2>How about reducing transmission?</h2>
<p>The next question is how well these vaccines reduce transmission of the virus from person to person, which the randomised clinical trials were not designed to measure directly.</p>
<p>Researchers in the UK linked data from the vaccination register with laboratory results and residential addresses. They showed a vaccinated household member who then developed COVID-19 was <a href="https://www.nejm.org/doi/full/10.1056/NEJMc2107717">half as likely</a> to transmit the virus to another household member as someone who had not been vaccinated.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1407628308389396482"}"></div></p>
<p>However, researchers did not measure the impact of vaccination on transmissibility of the Delta variant in this study as it was conducted before this became dominant in the UK.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/mounting-evidence-suggests-covid-vaccines-do-reduce-transmission-how-does-this-work-160437">Mounting evidence suggests COVID vaccines do reduce transmission. How does this work?</a>
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<h2>How about effectiveness against viral variants?</h2>
<p>Researchers in the UK have released estimates of vaccine effectiveness against coronavirus variants. </p>
<p>The most <a href="https://media.tghn.org/articles/Effectiveness_of_COVID-19_vaccines_against_hospital_admission_with_the_Delta_B._G6gnnqJ.pdf">recent report</a> from England found a single dose of the AstraZeneca or Pfizer vaccines provides only modest protection (30-40%) against infection with the Delta variant. Full vaccination with two doses of Pfizer offers greater protection (88%) than two doses of AstraZeneca (67%).</p>
<p>However, the same report found full vaccination with either vaccine provides more than 90% protection against hospitalisation from COVID-19.</p>
<p>A study in Scotland found <a href="https://www.thelancet.com/action/showPdf?pii=S0140-6736%2821%2901358-1">very similar results</a>.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/should-i-get-my-second-astrazeneca-dose-yes-it-almost-doubles-your-protection-against-delta-163259">Should I get my second AstraZeneca dose? Yes, it almost doubles your protection against Delta</a>
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<h2>What about vaccine side effects?</h2>
<p>Common side-effects of vaccines are tracked by the <a href="https://covid.joinzoe.com/">Zoe COVID Symptom Study</a>. This allows over four million people, mainly in the UK, to report any side-effects via an app.</p>
<p>Reported side-effects are <a href="https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(21)00224-3/fulltext">generally mild</a> (headache and fatigue). About 13% report common side-effects after the first dose of the Pfizer vaccine, 22% after the second dose. With AstraZeneca, it’s more than 33% after the first dose. Data from the second AstraZeneca dose were not available for this study.</p>
<figure class="align-center ">
<img alt="Middle-aged woman sitting on sofa scrolling smartphone" src="https://images.theconversation.com/files/409223/original/file-20210701-21135-1yd70d1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/409223/original/file-20210701-21135-1yd70d1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/409223/original/file-20210701-21135-1yd70d1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/409223/original/file-20210701-21135-1yd70d1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/409223/original/file-20210701-21135-1yd70d1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/409223/original/file-20210701-21135-1yd70d1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/409223/original/file-20210701-21135-1yd70d1.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">
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<span class="caption">Millions of people can report any suspected side-effects of COVID vaccines via an app.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/pleasant-senior-older-lady-resting-on-1667439751">from www.shutterstock.com</a></span>
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<p>The Zoe app has not quantified the risk of rare severe complications of vaccination. However, real-world data have provided <a href="https://www.bmj.com/content/373/bmj.n1114">early estimates</a> of the risk of a blood clot (thrombosis) after receiving the AstraZeneca vaccine in Norway and Denmark. </p>
<p>The overall rate of a blood clot in the veins anywhere in the body was approximately doubled compared to the general population. This included an extra risk of cerebral venous thrombosis (a type of brain blood clot) of 2.5 out of every 100,000 who received a first vaccination (compared with the general population). Although elevated, this is a very low risk.</p>
<p>The researchers did not have access to appropriate control groups receiving other COVID-19 vaccines to compare the levels of risk. This will likely be a priority in future studies.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/concerned-about-the-latest-astrazeneca-news-these-3-graphics-help-you-make-sense-of-the-risk-162175">Concerned about the latest AstraZeneca news? These 3 graphics help you make sense of the risk</a>
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<h2>How do we know all this?</h2>
<p>The science of analysing and interpreting real-world data from vaccine and other treatments has developed over the past 20 years.</p>
<p>In clinical trials randomisation of participants to treatment or control results in very similar comparison groups. This means any differences in trial outcomes should be due to the treatment, not some other factor. Real-world comparisons do not provide this guarantee. </p>
<p>If elderly people, with underlying disease, receive their vaccine early in the rollout, this may create a sicker group of people (or cohort) to follow and analyse. This may make the vaccine appear less-effective than it really is.</p>
<p>Conversely, a more open rollout may lead to more healthy people getting vaccinated. So, the vaccine will appear better (more effective) than it really is. </p>
<p>This complex interplay of biases makes it difficult for researchers to tease out the true effects of vaccines; hence real-world studies require more sophisticated designs and analyses than randomised trials.</p>
<p>However, it’s not so simple. Randomised trials can also be “real world” when they include broad criteria of who to include. While we need <a href="http://www.bmj.com/content/372/bmj.n435">more randomised trials</a>, they will never answer all the emerging questions soon enough. That’s why real-world data are so powerful in the middle of a pandemic.</p>
<h2>Where to next?</h2>
<p>Despite some limitations, analyses of real-world data have become increasingly important with the emergence of new, more infectious strains of SARS-CoV-2 as they can provide answers to important questions more quickly than randomised trials.</p>
<p>However, not all governments provide secure access to de-identified population-scale data to allow researchers to do this. So it’s essential suitably qualified researchers have this access to perform this important work.</p><img src="https://counter.theconversation.com/content/162926/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>David Henry also has an affiliation with Gold Coast University Hospital, Queensland, Australia</span></em></p><p class="fine-print"><em><span>Paul Glasziou 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>AstraZeneca, Pfizer and Moderna appear equivalent in reducing your chance of serious illness from COVID-19.David Henry, Professor of Evidence-Based Practice, Institute for Evidence-Based Healthcare, Bond UniversityPaul Glasziou, Professor of Medicine, Bond UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1611852021-06-16T20:10:21Z2021-06-16T20:10:21ZWhich COVID vaccine is best? Here’s why that’s really hard to answer<figure><img src="https://images.theconversation.com/files/406594/original/file-20210615-13-1g97ouf.jpg?ixlib=rb-1.1.0&rect=2%2C4%2C995%2C661&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/photo-pretty-lady-social-distancing-not-1748934254">Shutterstock</a></span></figcaption></figure><p>With the rollout of COVID-19 vaccines accelerating, people are increasingly asking <a href="https://trends.google.com/trends/explore?q=which%20vaccine%20is%20the%20best%20for%20covid">which vaccine is best</a>?</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/406650/original/file-20210616-3721-ufb675.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/406650/original/file-20210616-3721-ufb675.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=438&fit=crop&dpr=1 600w, https://images.theconversation.com/files/406650/original/file-20210616-3721-ufb675.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=438&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/406650/original/file-20210616-3721-ufb675.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=438&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/406650/original/file-20210616-3721-ufb675.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=551&fit=crop&dpr=1 754w, https://images.theconversation.com/files/406650/original/file-20210616-3721-ufb675.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=551&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/406650/original/file-20210616-3721-ufb675.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=551&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">According to Google Trends, more and more people want to know.</span>
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<p>Even if we tried to answer this question, defining which vaccine is “best” is not simple. Does that mean the vaccine better at protecting you from serious disease? The one that protects you from whichever variant is circulating near you? The one that needs fewer booster shots? The one for your age group? Or is it another measure entirely?</p>
<p>Even if we could define what’s “best”, it’s not as if you get a choice of vaccine. Until a suite of vaccines become available, the vast majority of people around the world will be vaccinated with whichever vaccine is available. That’s based on available clinical data and health authorities’ recommendations, or by what your doctor advises if you have an underlying medical condition. So the candid answer to which COVID vaccine is “best” is simply the one available to you right now. </p>
<p>Still not convinced? Here’s why it’s so difficult to compare COVID vaccines.</p>
<h2>Clinical trial results only go so far</h2>
<p>You might think clinical trials might provide some answers about which vaccine is “best”, particularly the large phase 3 trials used as the basis of approval by regulatory authorities around the world.</p>
<p>These trials, usually in tens of thousands of people, compare the number of COVID-19 cases in people who get the vaccine, versus those who get a placebo. This gives a measure of efficacy, or how well the vaccine works under the tightly controlled conditions of a clinical trial.</p>
<p>And we know the efficacy of different COVID vaccines differ. For instance, we learned from clinical trials that the Pfizer vaccine reported an <a href="https://www.nejm.org/doi/full/10.1056/NEJMoa2034577">efficacy of 95%</a> in preventing symptoms, whereas AstraZeneca had an efficacy of <a href="https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)32661-1/fulltext">62-90%</a>, depending on the dosing regime.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/how-to-read-results-from-covid-vaccine-trials-like-a-pro-149916">How to read results from COVID vaccine trials like a pro</a>
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<p>But direct comparison of phase 3 trials <a href="https://www.nature.com/articles/d41586-021-00409-0">is complex</a> as they take place at different locations and times. This means rates of infection in the community, public health measures and the mix of distinct viral variants can vary. Trial participants can also differ in age, ethnicity and potential underlying medical conditions.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/BRKZh_RXJC0?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">It’s tempting to compare COVID vaccines. But in a pandemic, when vaccines are scarce, that can be dangerous.</span></figcaption>
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<h2>We might compare vaccines head to head</h2>
<p>One way we can compare vaccine efficacy directly is to run head-to-head studies. These compare outcomes of people receiving one vaccine with those who receive another, in the same trial.</p>
<p>In these trials, how we measure efficacy, the study population and every other factor is the same. So we know any differences in outcomes must be down to differences between the vaccines.</p>
<p>For instance, a head-to-head trial is <a href="https://www.globenewswire.com/news-release/2021/04/21/2214528/0/en/Valneva-Initiates-Phase-3-Clinical-Trial-for-its-Inactivated-Adjuvanted-COVID-19-Vaccine-Candidate-VLA2001.html">under way in the UK</a> to compare the AstraZeneca and <a href="https://theconversation.com/whats-the-valneva-covid-19-vaccine-the-french-shot-thats-supposed-to-be-variant-proof-160345">Valneva</a> vaccines. The phase 3 trial is expected to be completed later this year.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1397849984322637827"}"></div></p>
<h2>How about out in the real world?</h2>
<p>Until we wait for the results of head-to-head studies, there’s much we can learn from how vaccines work in the general community, outside clinical trials. Real-world data tells us about vaccine effectiveness (not efficacy).</p>
<p>And the effectiveness of COVID vaccines can be compared in countries that have rolled out different vaccines to the same populations. </p>
<p>For instance, the latest data from the UK show both Pfizer and AstraZeneca vaccines have <a href="https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/988193/Vaccine_surveillance_report_-_week_20.pdf">similar effectiveness</a>. They <a href="https://www1.racgp.org.au/newsgp/clinical/evidence-indicates-astrazeneca-and-pfizer-covid-va">both reliably prevent COVID-19</a> symptoms, hospitalisation and death, even after a single dose.</p>
<p>So what at first glance looks “best” according to efficacy results from clinical trials doesn’t always translate to the real world.</p>
<h2>What about the future?</h2>
<p>The COVID vaccine you get today is not likely to be your last. As immunity naturally wanes after immunisation, periodic boosters will become necessary to maintain effective protection.</p>
<p>There is now <a href="https://www.nature.com/articles/d41586-021-01359-3">promising data from Spain</a> that mix-and-matching vaccines is safe and can trigger very potent immune responses. So this may be a viable strategy to maintain high vaccine effectiveness over time.</p>
<p>In other words, the “best” vaccine might in fact be a number of different vaccines.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1396971762085023746"}"></div></p>
<p>Variant viruses have started to circulate, and while current vaccines show reduced protection against these variants, <a href="https://theconversation.com/whats-the-indian-variant-responsible-for-victorias-outbreak-and-how-effective-are-vaccines-against-it-161574">they still protect</a>.</p>
<p><a href="https://www.afr.com/policy/health-and-education/australia-negotiating-with-three-vaccine-makers-for-boosters-variants-20210427-p57ms6">Companies</a>, <a href="https://www.bmj.com/content/372/bmj.n232">including Moderna</a>, are rapidly updating their vaccines to be administered as variant-specific boosters to combat this.</p>
<p>So, while one vaccine might have a greater efficacy in a phase 3 trial, that vaccine might not necessarily be “best” at protecting against future variants of concern circulating near you.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/can-i-get-astrazeneca-now-and-pfizer-later-why-mixing-and-matching-covid-vaccines-could-help-solve-many-rollout-problems-161404">Can I get AstraZeneca now and Pfizer later? Why mixing and matching COVID vaccines could help solve many rollout problems</a>
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<hr>
<h2>The best vaccine is the one you can get now</h2>
<p>It is entirely rational to want the “best” vaccine available. But the best vaccine is the one available to you right now because it stops you from catching COVID-19, <a href="https://theconversation.com/mounting-evidence-suggests-covid-vaccines-do-reduce-transmission-how-does-this-work-160437">reduces transmission</a> to vulnerable members of our community and substantially reduces your risk of severe disease. </p>
<p>All available vaccines do this job and do it well. From a collective perspective, these benefits are compounded. The more people get vaccinated, the more the community becomes immune (also known as herd immunity), further curtailing the spread of COVID-19. </p>
<p>The global pandemic is a highly dynamic situation, with emerging viral variants of concern, uncertain global vaccine supply, patchy governmental action and potential for explosive outbreaks in many regions. </p>
<p>So waiting for the perfect vaccine is an unattainable ambition. Every vaccine delivered is a small but significant step towards global normality.</p><img src="https://counter.theconversation.com/content/161185/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors 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>Even if we came up with a definition of what makes the “best” vaccine, we don’t have the luxury of choice, when vaccines are in short supply.Wen Shi Lee, Postdoctoral researcher, The Peter Doherty Institute for Infection and ImmunityHyon Xhi Tan, Postdoctoral researcher, The Peter Doherty Institute for Infection and ImmunityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1615742021-05-27T06:46:48Z2021-05-27T06:46:48ZWhat’s the ‘Indian’ variant responsible for Victoria’s outbreak and how effective are vaccines against it?<figure><img src="https://images.theconversation.com/files/403108/original/file-20210527-20-rq2rth.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://photos.aap.com.au/">Luis Ascui/AAP</a></span></figcaption></figure><p>Victoria’s seven day lockdown, which <a href="https://www.theage.com.au/national/victoria/victoria-covid-live-updates-melbourne-braces-for-lockdown-as-health-officials-await-overnight-case-numbers-20210526-p57ve7.html">begins tonight</a>, is an attempt to stop transmission of the quick-spreading COVID-19 B.1.617.1 variant. </p>
<p>Victoria’s <a href="https://www.skynews.com.au/details/_6256183991001">chief health officer Brett Sutton said</a> the reproduction number of the strain was yet to be determined, but could be five or more, meaning one person would infect five others. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1397740878794354688"}"></div></p>
<p>B.1.617.1 is one of three so-called “Indian” SARS-CoV-2 variant sub-types. Little is known about it but it’s likely to have similar characteristics to the sub-type dominating in India and emerging in the United Kingdom at the moment, B.1.617.2. </p>
<h2>Remind me, what’s a variant of concern?</h2>
<p>To be classified as a variant of concern, it must pose a risk to public health over and above the original Wuhan virus. This could be due to changes in transmissibility (how easily it spreads), disease severity, its ability to evade detection by viral diagnostic tests, reduced effectiveness of treatments, or an ability to evade natural or vaccine-induced immunity.</p>
<p>The World Health Organization is <a href="https://reliefweb.int/sites/reliefweb.int/files/resources/20210525_Weekly_Epi_Update_41.pdf">tracking</a> four variants of concern, which are often referred to by the country in which they emerged: </p>
<ul>
<li>the UK (B.1.1.7)</li>
<li>South Africa (B.1.351)</li>
<li>Brazil (P.1)</li>
<li><a href="https://www.biorxiv.org/content/10.1101/2021.04.22.440932v1">Indian variant (B.1.617)</a>.</li>
</ul>
<p>The B.1.617 variant, which was classified as a <a href="https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/984274/Variants_of_Concern_VOC_Technical_Briefing_10_England.pdf">variant of concern</a> on May 6 2021, has three subtypes – B.1.617.1, B.1.617.2 and B.1.617.3 – each with small differences in their genetic make-up.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/whats-the-difference-between-mutations-variants-and-strains-a-guide-to-covid-terminology-154825">What's the difference between mutations, variants and strains? A guide to COVID terminology</a>
</strong>
</em>
</p>
<hr>
<h2>What do we know about the ‘Indian’ variants?</h2>
<p>Information about B.1.617 is emerging, but <a href="https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/984274/Variants_of_Concern_VOC_Technical_Briefing_10_England.pdf">early reports indicate</a> it spreads more easily than the original strain. Although there is limited data specifically on B.1.617.1, it is likely to behave similarly to B.1.617.2 as it is genetically similar. </p>
<p>Early data from the UK’s NHS Test and Trace records showed B.1.617 spreads at least as easily as the UK strain (B.1.1.7). In fact, B.1.617.2 may be <a href="https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/984274/Variants_of_Concern_VOC_Technical_Briefing_10_England.pdf">twice as likely to infect</a> another person than the UK strain, which was already more infectious than the original Wuhan virus.</p>
<p>The relative disease severity of B.1.617 is still under investigation, however even if it is no more severe than the original virus, increased transmission leads to more cases, more hospital admissions and more deaths. </p>
<p>Laboratory tests also raise the possibility <a href="https://www.biorxiv.org/content/10.1101/2021.04.23.441101v1">that reinfection might be more common</a> with the B.1.617 variant, but this is yet to be confirmed by real-world data and for all sub-types. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/why-variants-are-most-likely-to-blame-for-indias-covid-surge-159911">Why variants are most likely to blame for India's COVID surge</a>
</strong>
</em>
</p>
<hr>
<h2>How effective are vaccines and how long do they take to kick in?</h2>
<p>For most variants of concern, vaccines are still effective, but are often less effective than they were against the original Wuhan virus. </p>
<p>So far, there are no data on how effective any of the COVID-19 vaccines are against B.1.617.1. </p>
<p>B.1.617.2 has one more mutation than B.1.617.1, so they are genetically similar. Therefore the vaccine effectiveness against B.1.617.1 and B.1.617.2 is likely be similar, but this is not known yet. </p>
<hr>
<iframe src="https://flo.uri.sh/visualisation/6263170/embed" title="Interactive or visual content" frameborder="0" scrolling="no" style="width:100%;height:400px;" sandbox="allow-same-origin allow-forms allow-scripts allow-downloads allow-popups allow-popups-to-escape-sandbox allow-top-navigation-by-user-activation" width="100%" height="400"></iframe>
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<hr>
<p>Data from the UK (non-peer reviewed) on vaccine effectiveness against the B.1.617.2 variant has recently been <a href="https://khub.net/documents/135939561/430986542/Effectiveness+of+COVID-19+vaccines+against+the+B.1.617.2+variant.pdf/204c11a4-e02e-11f2-db19-b3664107ac42">released</a>. It found:</p>
<ul>
<li><p>both Pfizer and AstraZeneca are 33% effective against symptomatic disease (COVID-19 symptoms such as fever, dry cough and tiredness) three weeks after the first dose </p></li>
<li><p>Pfizer vaccine is 88% effective against symptomatic disease two weeks after the second dose </p></li>
<li><p>AstraZeneca vaccine is 60% effective against symptomatic disease two weeks after the second dose.</p></li>
</ul>
<p>The difference in effectiveness between the vaccines after two doses may be due to AstraZeneca taking longer <a href="https://khub.net/documents/135939561/430986542/Effectiveness+of+COVID-19+vaccines+against+the+B.1.617.2+variant.pdf/204c11a4-e02e-11f2-db19-b3664107ac42">to reach peak protection</a> as this occurs after two weeks following the second dose. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1397732002124685312"}"></div></p>
<p>Both vaccines are expected to provide even greater protection against COVID-19 hospitalisation and death than they do for symptomatic disease. As yet there are too few cases to do this analysis but this will take place over the coming <a href="https://www.gov.uk/government/news/vaccines-highly-effective-against-b-1-617-2-variant-after-2-doses">weeks</a>. </p>
<p>Lower vaccine effectiveness means even if you are vaccinated, you could <a href="https://www.cdc.gov/vaccines/acip/meetings/downloads/slides-2021-05-12/10-COVID-Scobie-508.pdf">still get infected</a>. However, if an infection does occur, symptoms would be milder. </p>
<p>It’s also <a href="https://science.sciencemag.org/content/371/6534/1103">possible</a> vaccination may not protect you for as long against this sub-type compared to other variants. But this is not known yet for B.1.617.1.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/whats-the-new-coronavirus-variant-in-india-and-how-should-it-change-their-covid-response-157957">What's the new coronavirus variant in India and how should it change their COVID response?</a>
</strong>
</em>
</p>
<hr>
<h2>Time between doses</h2>
<p>From December 2020, the UK had been delivering the AstraZeneca and Pfizer vaccines with a 12-week interval between doses to <a href="https://www.gov.uk/government/news/statement-from-the-uk-chief-medical-officers-on-the-prioritisation-of-first-doses-of-covid-19-vaccines">provide some protection to as many people as possible</a>. </p>
<p>A <a href="https://www.medrxiv.org/content/10.1101/2021.05.15.21257017v1">recent study</a> supported this decision, finding that extending the vaccine interval from three to 12 weeks for the second dose boosted the immune response in people over 80 by 3.5 times. </p>
<p>However, due to the spread of the B.1.617.2 variant in the UK, the strategy was <a href="https://www.gov.uk/government/news/most-vulnerable-offered-second-dose-of-covid-19-vaccine-earlier-to-help-protect-against-variants">changed in mid-May to an eight-week gap in order to provide greater protection</a> from this highly transmissible virus at an earlier opportunity. </p>
<p>Australia delivers the AstraZeneca vaccine with a 12-week interval, while opting for three weeks for Pfizer. </p>
<p>Decisions on the timing between doses must balance providing greater protection earlier, against providing some protection to the maximum number of people. It’s too early to make those changes right now for Victoria but this option should be considered if the outbreak worsens. </p>
<figure class="align-center ">
<img alt="People waiting for vaccinations." src="https://images.theconversation.com/files/403079/original/file-20210527-23-1cabpt1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/403079/original/file-20210527-23-1cabpt1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=419&fit=crop&dpr=1 600w, https://images.theconversation.com/files/403079/original/file-20210527-23-1cabpt1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=419&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/403079/original/file-20210527-23-1cabpt1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=419&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/403079/original/file-20210527-23-1cabpt1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=527&fit=crop&dpr=1 754w, https://images.theconversation.com/files/403079/original/file-20210527-23-1cabpt1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=527&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/403079/original/file-20210527-23-1cabpt1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=527&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Australia currently has a 12-week gap between AstraZeneca doses.</span>
<span class="attribution"><a class="source" href="https://photos.aap.com.au/">Luis Ascui/Shutterstock</a></span>
</figcaption>
</figure>
<h2>Should people get vaccinated?</h2>
<p>Even though we don’t know how effective vaccines are against the B.1.617.1 sub-type, don’t delay getting vaccinated. This time our outbreak is due to B.1.617.1, but next time it could be another variant. </p>
<p>COVID-19 vaccines are equally effective against the original strain and B.1.1.7, and are also effective against the B.1.617.2 variant (albeit a bit lower). </p>
<p>During an outbreak, policymakers should also consider opportunistically increasing vaccine uptake, <a href="https://protect-au.mimecast.com/s/RR0gCr8Dz5s89MO5JS75CR9?domain=www1.health.gov.au">especially in the outbreak areas</a>. Victoria has made progress in this area and from <a href="https://www.premier.vic.gov.au/vaccine-roll-out-expand-all-victorians-40-and-over">tomorrow</a> all 40- to 49-year-old Victorians will be offered Pfizer. </p>
<p>But those responsible for the most COVID-19 transmission are <a href="https://science.sciencemag.org/content/sci/early/2021/02/01/science.abe8372.full.pdf">aged 20 to 49 years</a>. So vaccinating even younger Victorians – 20 to 39 year olds – would also prevent spread of the outbreak. Even if the vaccine was only 20% effective against transmission this may be a very important additional measure. </p>
<p>Even though there are many unknowns, it is still important to get vaccinated with the vaccine that is offered right now.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/im-over-50-and-can-now-get-my-covid-vaccine-is-the-astrazeneca-vaccine-safe-does-it-work-what-else-do-i-need-to-know-159814">I'm over 50 and can now get my COVID vaccine. Is the AstraZeneca vaccine safe? Does it work? What else do I need to know?</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/161574/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Professor Fiona Russell receives funding from NHMRC, the Wellcome Trust, WHO, DFAT, and the Bill & Melinda Gates Foundation.</span></em></p><p class="fine-print"><em><span>Katherine Gibney receives funding from MRFF, NHMRC, Royal Australasian College of Physicians (RACP-GlaxoSmithKline Research Establishment Fellowship), the Prior Foundation and the Gilbertson Charitable Trust. </span></em></p><p class="fine-print"><em><span>John Hart 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 COVID-19 variant responsible for Victoria’s latest outbreak is one of three Indian variant sub-types, which spreads more easily than the original strain. Here’s what we know so far.Fiona Russell, Senior Principal Research Fellow; paediatrician; infectious diseases epidemiologist, The University of MelbourneJohn Hart, Clinical researcher, Murdoch Children's Research InstituteKatherine Gibney, Senior research fellow, The Peter Doherty Institute for Infection and ImmunityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1615512021-05-26T17:30:49Z2021-05-26T17:30:49ZCOVID vaccine weekly: both vaccine doses needed for good protection against B16172 variant<p>It’s been a concerning few weeks in the UK, with the B16172 variant first taking hold and then spreading to become dominant. This more infectious form of the virus, initially identified in India, is what we’re now going to have to live with – unless it is out-competed by another variant in the future.</p>
<p>Worryingly, experts had <a href="https://theconversation.com/q-a-indian-coronavirus-variant-what-is-it-and-what-effect-will-it-have-159269">predicted</a> that B16172 might be able to escape some of the effects of vaccines, which if true would threaten to derail the UK’s plans to finish lifting restrictions from the end of June. However, Public Health England (PHE) has looked at the ability of various variants to evade immunity, and says that the UK’s vaccines remain effective against the variants circulating, including B16172.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/q-a-indian-coronavirus-variant-what-is-it-and-what-effect-will-it-have-159269">Q+A: Indian coronavirus variant – what is it and what effect will it have?</a>
</strong>
</em>
</p>
<hr>
<p>On the surface, this looks like good news. But delve a bit deeper, and things get more complicated, <a href="https://theconversation.com/b16172-variant-the-uk-needs-to-brace-for-more-cases-despite-vaccine-effectiveness-161455">says</a> Paul Hunter, professor of medicine at the University of East Anglia. PHE’s research found little drop-off in protection against B16172 among people who were fully vaccinated. But among those who have received just one dose, protection is considerably lower against B16172 compared to the previously dominant one, B117.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/b16172-variant-the-uk-needs-to-brace-for-more-cases-despite-vaccine-effectiveness-161455">B16172 variant: the UK needs to brace for more cases, despite vaccine effectiveness</a>
</strong>
</em>
</p>
<hr>
<p>Plus, we can be pretty confident that B16172 is more infectious than earlier variants. This will magnify the effect of any drop in protection, meaning the UK could be about to witness a new spike in cases. Any prospect of a third wave arriving could have serious implications for the final stage of reopening in June. </p>
<hr>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/320716/original/file-20200316-18073-ruhw8b.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/320716/original/file-20200316-18073-ruhw8b.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/320716/original/file-20200316-18073-ruhw8b.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/320716/original/file-20200316-18073-ruhw8b.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/320716/original/file-20200316-18073-ruhw8b.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/320716/original/file-20200316-18073-ruhw8b.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/320716/original/file-20200316-18073-ruhw8b.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
</figcaption>
</figure>
<p><em><strong>This is our weekly round-up of expert information about the <a href="https://theconversation.com/uk/topics/covid-vaccines-96571">COVID-19 vaccines</a>.</strong> <br>
The Conversation, a not-for-profit group, works with a wide range of academics across its global network to produce evidence-based analysis and insights. Get more regular updates from trusted experts by <a href="https://theconversation.com/uk/newsletters/the-daily-2">subscribing to our free newsletter</a> .</em></p>
<hr>
<p>However, there’s an important caveat here, <a href="https://theconversation.com/coronavirus-so-many-variants-but-vaccines-are-still-effective-161222">argues</a> Luke O'Neill, professor of biochemistry at Trinity College Dublin. PHE’s analyses are concerned with the risk of infection. But really, the most important question when considering the effects of variants breaking through vaccine protection is not whether someone gets infected, but whether they become severely ill or die.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/coronavirus-so-many-variants-but-vaccines-are-still-effective-161222">Coronavirus: so many variants, but vaccines are still effective</a>
</strong>
</em>
</p>
<hr>
<p>So far, we don’t have an answer to whether B16172 causes more severe illness, or if vaccines still offer protection against severe illness if they fail to stop people developing COVID-19 symptoms. But, given the amounts of antibodies the vaccines typically get people to generate – as well as how effective they are at stimulating the immune system’s T cell response – it’s a reasonable prospect that they’ll remain highly effective at blocking the worst effects of COVID-19.</p>
<p>As Paul Hunter <a href="https://theconversation.com/b16172-variant-the-uk-needs-to-brace-for-more-cases-despite-vaccine-effectiveness-161455">notes</a>, we should have a better sense of how B16172 is affecting hospitalisation and death rates in the next few weeks. If these remain unaffected, then it’s far more likely that the UK’s exit from lockdown will be unaffected too. </p>
<hr>
<p><em>Get the latest news and advice on <a href="https://theconversation.com/uk/covid-19">COVID-19</a>, direct from the experts in your inbox. Join hundreds of thousands who trust experts by <strong><a href="https://theconversation.com/uk/newsletters/the-daily-2">subscribing to our newsletter</a></strong>.</em></p><img src="https://counter.theconversation.com/content/161551/count.gif" alt="The Conversation" width="1" height="1" />
New, early-stage research suggest that B16172 does have some ability to escape the effects of vaccines.Rob Reddick, Commissioning Editor, COVID-19Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1612222021-05-24T12:54:49Z2021-05-24T12:54:49ZCoronavirus: so many variants, but vaccines are still effective<p>Viruses are constantly changing. This is because errors sometimes occur when they copy their genetic material. Some errors have no effect at all. Some might make the virus less viable. Some make it more benign, which means it can survive but doesn’t cause disease. The errors to watch for are those that might make the virus more infectious, or better able to avoid the immune system that is trying to counter them, either driven by natural infection or stimulated by a vaccine. </p>
<p>SARS-CoV-2, the virus that causes COVID-19, is no different. Each time it divides, it rolls the dice, which could give rise to a more malign virus. This can happen anywhere, anytime. So it’s important to track variants and to see if they are spreading more easily from person to person, causing more mild or more severe disease, might avoid detection with current tests, or might respond less well to current treatments. Perhaps the biggest concern is breakthrough infections, where a fully vaccinated person <a href="https://theconversation.com/covid-vaccines-some-fully-vaccinated-people-will-still-get-infected-heres-why-160131">still gets COVID</a>.</p>
<p>Once a variant is spotted, it is classified as being either a variant of interest, a variant of concern or a variant of high consequence. Mercifully, we have yet to see a variant of high consequence, which are variants against which current medical measures are failing. But we have at least <a href="https://www.cdc.gov/vaccines/acip/meetings/downloads/slides-2021-05-12/10-COVID-Scobie-508.pdf">four variants of concern</a>. </p>
<p>That designation means there is evidence of increased transmissibility, more severe disease, a significant reduction in antibody neutralisation or reduced effectiveness of vaccines or treatments. These are B117 (first identified in the UK), B1351 (first identified in South Africa), P1 (first identified in Brazil) and B16172 (first identified in India). </p>
<p>There is evidence that all of these have increased transmissibility and there is a <a href="https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(21)00262-0/fulltext">good molecular</a> <a href="https://www.nature.com/articles/s41467-021-21118-2">understanding</a> of <a href="https://www.biorxiv.org/content/10.1101/2021.02.22.432189v1">why that is</a>. </p>
<p>Increased transmissibility can be observed epidemiologically (in the population), but it’s also important to confirm in a lab why that particular variant of concern can transmit more readily. The spike protein, which is the part of the virus that latches onto a receptor on human cells called ACE2, has changed in each of these variants of concern, and the change has been shown in some of them to increase the virus’s ability to bind to ACE2. </p>
<p>Some lab studies have shown that antibodies made to target the original spike protein are less able to neutralise the spike protein in the variants of concern. But, more important, so-called real-world data (which, in this case, means assessing a situation where a vaccine against the older SARS-CoV-2 has been used, but a variant of concern is the main virus in circulation) has indicated that this doesn’t have a big effect on vaccine effectiveness against some of the variants. </p>
<p>A very <a href="https://www.nejm.org/doi/full/10.1056/NEJMc2104974">hopeful study</a> from Qatar showed that the Pfizer/BioNTech vaccine was 90% effective against B117 and 75% effective against B1351. The AstraZeneca vaccine showed 75% effectiveness against B117. </p>
<h2>Vaccines highly effective against B16172</h2>
<p>Public Health England has reported that both the Pfizer/BioNTech and AstraZeneca vaccines are <a href="https://www.google.com/amp/s/www.bbc.com/news/uk-57214596.amp">highly effective against B16172</a>. Pfizer/BioNTech reached 88% effectiveness, while AstraZeneca achieved a level of 60%. This lower effectiveness for AstraZeneca might be because the rollout of the second shot of AstraZeneca was later than Pfizer/BioNTech. This study is important because it looks as though the B16172 variant may well become the dominant variant globally, replacing B117.</p>
<p>These analyses are all concerned with the risk of infection. The most important question, however, when it comes to the possibility of variants breaking through a vaccine is not whether someone gets infected, but whether that infection progresses to severe disease or death. </p>
<p>A vaccine’s job is to stop severe disease – and so far it is a reasonable prospect that the main vaccines in use should be able to do that against the variants of concern. This is probably partly due to the strong antibody response elicited by each vaccine. Even though the quality of the antibodies might be less, antibodies can make up for that with quantity. Think of antibodies as Blu-Tack. They can stick to the spike protein, and although they can get less sticky, the more there is, the more will stick. </p>
<p>And even if the power of antibodies were to be diminished, the immune system has another trick up its sleeve: T cells. T cells will recognise many parts of the virus (these are called epitopes). One recent analysis has concluded there are around <a href="https://www.cell.com/cell-host-microbe/fulltext/S1931-3128(21)00238-9">1,400 of these</a> targets on SARS-CoV-2. On recognising a part of the virus, T cells can do two things: they can help the B cells to make lots of antibodies, or they can kill the infected cell. The killer T cell response might well kick in after the infection has started. The chances of T cells failing against variants is low. All of this should give us confidence. </p>
<p>Scientists are also trying to predict how much of an antibody response is needed to ensure protection against variants, to get a good idea of the <a href="https://www.nature.com/articles/s41591-021-01377-8">risk of vaccine failure</a>. Perhaps most importantly of all, it will be possible to vaccinate with booster shots with spike protein or mRNA from variants of concern, and there are even moves afoot to come up with a vaccine to <a href="https://theconversation.com/a-single-vaccine-to-beat-all-coronaviruses-sounds-impossible-but-scientists-are-already-working-on-one-156373">protect against all coronaviruses</a>. The pharmaceuticals company Novavax is even testing <a href="https://www.reuters.com/business/healthcare-pharmaceuticals/novavax-combined-influenzacovid-19-vaccine-shows-promise-preclinical-study-2021-05-10/">a combined flu/COVID vaccine</a>. </p>
<p>There is always the chance of other variants of concern emerging. More malign ones may crop up, although that is <a href="https://theconversation.com/can-scientists-predict-all-of-the-ways-the-coronavirus-will-evolve-156673">difficult to predict</a>, so it’s critical that we get vaccines to the countries that need them most, to forestall the possibility of more dangerous variants cropping up. What we’re also learning is it’s important to have the second shot of the vaccines that require them. The one-shot Johnson and Johnson vaccine might well <a href="https://edition.cnn.com/2021/05/22/health/covid-19-vaccine-boosters-explainer-wellness/index.html">need a booster</a>, too. A third booster shot for the other vaccines might work too, as that will bring out a huge antibody and T cell response. </p>
<p>It’s clear what needs to be done when it comes to these variants: keep hunting for them, ensure universal vaccination and get ready for booster shots.</p><img src="https://counter.theconversation.com/content/161222/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Luke O'Neill 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>Variants of interest and variants of concern seem to be popping up at an alarming rate. But how many of them do we really need to worry about?Luke O'Neill, Professor, Biochemistry, Trinity College DublinLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1608882021-05-18T12:25:01Z2021-05-18T12:25:01ZUK vaccine booster Q&A: what will be given and when, explained by public health expert<figure><img src="https://images.theconversation.com/files/401242/original/file-20210518-17-q93hee.jpg?ixlib=rb-1.1.0&rect=32%2C123%2C5292%2C3273&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/elderly-man-getting-coronavirus-vaccine-1893080998">Melinda Nagy/Shutterstock</a></span></figcaption></figure><p>The national effort to immunise the UK population against COVID-19 has been phenomenal. In six months, more than <a href="https://coronavirus.data.gov.uk/details/vaccinations">56 million vaccine doses</a> have been given to over 36 million people. With the distribution of first and second doses going well, the British government is now considering if and when it should give people a third, booster dose.</p>
<p>However, <a href="https://www.bbc.co.uk/news/live/uk-56991714">reports</a> so far have been <a href="https://metro.co.uk/2021/05/08/uk-will-be-covid-free-by-august-and-booster-jabs-can-be-pushed-back-14543145/">contradictory</a>. They’ve offered <a href="https://www.thetimes.co.uk/article/third-covid-vaccine-for-over-50s-before-winter-jhpj57g0d">different suggestions</a> on when boosters will be given, who they’ll be given to, and what exactly people might receive. But while it’s impossible to say for sure what will happen in the future, based on what we know about COVID-19 and the pandemic, it is possible to predict broadly how a booster programme could operate.</p>
<p>Undoubtedly, there’s a desire to end lockdown restrictions, reopen the country and keep it open – and this is why a third vaccine dose is being considered. Reopening safely will require two key conditions to be met: firstly, that most people get vaccinated, and secondly, that the vaccines remain effective. Boosters may be needed to ensure the latter. Here’s how they might work.</p>
<h2>Who will be offered a third vaccine?</h2>
<p>People whose earlier vaccine protection may have worn off are likely to be prioritised.</p>
<p>Currently, it’s not certain how long COVID-19 vaccine protection lasts, though studies suggest <a href="https://www.nejm.org/doi/10.1056/NEJMc2103916">at least six months</a>. However, vaccine protection varies by individual and naturally wanes over time. For some people, this waning happens more rapidly, for <a href="https://www.immunology.org/sites/default/files/BSI_Briefing_Note_2021_immunity_COVID19.pdf">reasons</a> such as old age, the effect of some chronic illness, or taking treatments that may suppress the immune system. </p>
<p>Consequently, a booster dose is likely to be needed for people in these high-risk groups to make sure good immune protection is maintained. Indeed, the UK’s Department of Health and Social Care has said that boosters will be distributed <a href="https://www.bmj.com/content/373/bmj.n1116?ijkey=44035bce6459ec0384787104b692612c0ab153cc&keytype2=tf_ipsecsha">based on clinical need</a>. </p>
<h2>When might boosters start being given?</h2>
<p>Ahead of when future waves of infection are anticipated. Epidemics of human coronaviruses are usually <a href="https://academic.oup.com/jid/article/222/1/17/5820656?login=true">seasonal in nature</a>, typically occurring in the winter months. Thus, the ideal timing for the vaccine booster programme will be in the autumn months so that most of the vulnerable population is protected in time for any winter outbreaks.</p>
<p>Current efforts are targeted at immunising the UK adult population with two doses <a href="https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/951928/uk-covid-19-vaccines-delivery-plan-final.pdf">by the autumn of 2021</a>. It’s likely that any vaccine booster programme will only begin afterwards. Indeed, the logistics of planning, procuring the boosters, distributing them and rolling them out is fairly complex. This may delay rollout to early 2022.</p>
<h2>Will the booster be an updated formula?</h2>
<p>So far, the vaccines in use in the UK are <a href="https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/971017/SP_PH__VE_report_20210317_CC_JLB.pdf">showing good efficacy</a> against circulating variants of the virus. On that basis, booster vaccines are likely to be the same as ones used previously. </p>
<p>However, a major concern is that a new variant emerges that can evade the immunity provided by existing vaccines – what’s known as “vaccine escape”. </p>
<p>Should an escape variant emerge, one strategy may be to boost people with the existing vaccine that has the best efficacy against it. For example, the B1351 variant identified in South Africa appears to have some escape potential, as the Oxford/AstraZeneca vaccine is <a href="https://www.cidrap.umn.edu/news-perspective/2021/03/astrazeneca-vaccine-doesnt-prevent-b1351-covid-early-trial">less effective</a> at preventing mild to moderate COVID-19 when facing it. However, <a href="https://www.nature.com/articles/d41586-021-01222-5">early research</a> – <a href="https://www.medrxiv.org/content/10.1101/2021.04.06.21254882v1">some of which</a> still needs to be reviewed by other scientists – suggests the Pfizer/BioNTech vaccine isn’t so severely affected.</p>
<p>If none of the existing vaccines are sufficiently effective, then updated vaccines may be needed. However, they will take time to alter and mass produce. In the meantime, we need to closely monitor and study both the emergence of new variants as well as the effectiveness of existing vaccines against them.</p>
<figure class="align-center ">
<img alt="Vials of the AstraZeneca, Pfizer and Moderna COVID-19 vaccines" src="https://images.theconversation.com/files/401243/original/file-20210518-17-1morxt3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/401243/original/file-20210518-17-1morxt3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/401243/original/file-20210518-17-1morxt3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/401243/original/file-20210518-17-1morxt3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/401243/original/file-20210518-17-1morxt3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/401243/original/file-20210518-17-1morxt3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/401243/original/file-20210518-17-1morxt3.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">Pfizer, Moderna and AstraZeneca have all started work on updated boosters to better handle the new variants.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/montreal-ca-16-march-2021-vials-1937221621">Marc Bruxelle/Shutterstock</a></span>
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</figure>
<h2>Will I get a booster from a different manufacturer?</h2>
<p>Possibly. Combining COVID-19 vaccines that <a href="https://theconversation.com/how-the-leading-coronavirus-vaccines-work-146969">generate immunity in different ways</a> – such as Pfizer’s and AstraZeneca’s – could generate a more powerful and long-lasting immune response. It could also allow for greater flexibility in rolling out a third dose, which might speed things up.</p>
<p>However, while in theory mixing doses could give an extra boost of immunity, <a href="https://comcovstudy.org.uk/home">research</a> is still trying to work out if this actually happens. UK scientists looking at mixing the Pfizer and AstraZeneca vaccines have so far found that <a href="https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(21)01115-6/fulltext">side-effects are more likely</a> when combining the two. On that basis, if an individual has reacted well to one vaccine, it may be sensible for the same vaccine to be used. </p>
<h2>Will I need another booster in the future?</h2>
<p>It will take more time to be sure, but again, possibly yes. This is still a new pandemic, and it’s <a href="https://science.sciencemag.org/content/372/6540/363">still not known conclusively</a> how long COVID-19 immunity lasts and how strong it will be. Based on what we know about the original Sars virus, <a href="https://www.jimmunol.org/content/186/12/7264.short">immune responses can last years</a> but may wane. What’s not known is whether these immune responses are sufficient to protect against severe illness or death.</p>
<p>It may therefore be prudent for people to be re-immunised against COVID-19 on an annual basis to maintain immunity, as <a href="https://www.nature.com/articles/d41586-021-00396-2">many scientists believe</a> the coronavirus will become endemic and circulate continually. If variants continue to emerge, then continually updated vaccines may become the norm, like for seasonal flu.</p>
<p>There’s also emerging evidence that COVID-19 vaccines don’t just protect against disease, but also <a href="https://www.cdc.gov/mmwr/volumes/70/wr/mm7020e2.htm?s_cid=mm7020e2_e">reduce the probability</a> of people spreading the virus by <a href="https://www.nature.com/articles/s41591-021-01316-7">reducing the amount of virus</a> infected people carry. Vaccinations could therefore be used on an ad hoc basis to quell outbreaks and emerging epidemics.</p>
<p>There remain many unanswered questions, and how the global pandemic will unfold in the next year is also uncertain. Vaccine policy decisions will need to be flexible and informed by emerging evidence of vaccine effectiveness and infection trends.</p><img src="https://counter.theconversation.com/content/160888/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Andrew Lee has previously received research funding from the National Institute for Health Research. He is a member of the UK Faculty of Public Health and the Royal Society for Public Health.</span></em></p>A public health expert outlines what Britons can expect from their upcoming booster programme.Andrew Lee, Reader in Global Public Health, University of SheffieldLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1608132021-05-17T11:37:55Z2021-05-17T11:37:55ZHow COVID vaccines have pushed the UK towards the end of lockdown<p>The latest round of <a href="https://www.theguardian.com/world/2021/may/16/britain-england-scotland-wales-changing-coronavirus-restrictions-17-may">lockdown easing</a> has now taken place in England, Wales and most of Scotland, with restrictions on households mixing indoors being relaxed to varying degrees across the three countries.</p>
<p>As with previous steps out of lockdown, <a href="https://www.gov.uk/government/speeches/pm-statement-to-the-house-of-commons-on-roadmap-for-easing-lockdown-restrictions-in-england-22-february-2021">four conditions</a> had to be met ahead of things reopening. Two of these focused on vaccines. The UK once again needed to show evidence of vaccines being successfully deployed and of them reducing COVID-19 hospitalisations and deaths in order for restrictions to ease.</p>
<p>The UK’s vaccine rollout has been one of the fastest in the world, with excellent uptake, so it’s clear that the deployment condition has been met. As of May 12, more than <a href="https://coronavirus.data.gov.uk/">two-thirds</a> of UK adults had been administered a first dose of a vaccine, with around half of these having received both.</p>
<p>There’s also been a continuing reduction in COVID-19 <a href="https://coronavirus.data.gov.uk/details/healthcare">hospitalisations</a> and <a href="https://coronavirus.data.gov.uk/details/deaths">deaths</a>, suggesting the second vaccine condition has been met too. But with lockdown running alongside the vaccination programme, and other measures such as social distancing and masks being used simultaneously too, how can we tell how much of this change is down to vaccines specifically?</p>
<iframe src="https://ourworldindata.org/explorers/coronavirus-data-explorer?zoomToSelection=true&time=2020-12-08..latest&pickerSort=desc&pickerMetric=new_cases_smoothed_per_million&Metric=Confirmed+deaths&Interval=7-day+rolling+average&Relative+to+Population=true&Align+outbreaks=false&country=USA~GBR~DEU~FRA~ESP~ISR&hideControls=true" loading="lazy" style="width: 100%; height: 600px; border: 0px none;" width="100%" height="400"></iframe>
<h2>Measuring vaccines’ effectiveness</h2>
<p>Phase 3 clinical trials tested the <a href="https://www.nejm.org/doi/full/10.1056/nejmoa2034577">Pfizer/BioNTech</a> and <a href="https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)32661-1/fulltext">Oxford/AstraZeneca</a> vaccines in thousands of people last year. This research found that the two vaccines were 95% and 70% effective respectively at preventing COVID-19 disease compared with unvaccinated people. But this was efficacy recorded under trial conditions; effectiveness in the real world <a href="https://theconversation.com/pfizer-vaccine-what-an-efficacy-rate-above-90-really-means-149849">isn’t always the same</a>.</p>
<p>So, as the UK’s vaccination programme started, it was crucial to understand how well the vaccines were actually working as the pandemic evolved – particularly with new variants arising. This is why the <a href="https://www.ed.ac.uk/usher/eave-ii/what-is-eave-ii">Early Pandemic Evaluation and Enhanced Surveillance of COVID-19 (EAVE-II)</a> platform was established – to collect data on the use of these vaccines to <a href="https://bmjopen.bmj.com/content/10/6/e039097">provide insight</a> into their effectiveness and safety in the real world. </p>
<p>EAVE-II tracked who was getting the vaccine, who then contracted COVID-19, and whether they needed to be treated in hospital and if they died after their infection. My colleagues and I then <a href="https://www.sciencedirect.com/science/article/pii/S0140673621006772">analysed</a> the data that EAVE-II had gathered from across almost the entire population of 5.4 million people in Scotland. </p>
<p>We found that between 28 and 34 days after a first dose, the Pfizer/BioNTech vaccine was 91% effective and the Oxford/AstraZeneca vaccine 88% effective in reducing COVID-19 hospitalisation compared with unvaccinated people. These results from a real-life setting back up the data from trials, showing how effective vaccines can be in protecting people from the worst effects of COVID-19. Importantly, they were also able to show that vaccines were proving highly effective at protecting people even while other protective measures (lockdown, social distancing, mask-wearing) were in place.</p>
<p><a href="https://www.gov.uk/government/news/one-dose-of-covid-19-vaccine-can-cut-household-transmission-by-up-to-half">Subsequent studies</a> have shown that the vaccines are also successful in reducing household transmission, cutting it by up to half. Together with our research, these studies show the importance of having a national linked dataset that brings together routinely collected electronic health records. Being able to quickly cross-reference people’s vaccination status and medical condition was essential for our research. </p>
<h2>What happens next?</h2>
<p>With the coronavirus mutating as it spreads, the question now is how well the current vaccines will perform against new variants.</p>
<p>The Oxford/AstraZeneca team <a href="https://paperclinis.ssrn.com/sol3/papers.cfm?abstract_id=3779160">conducted a quick trial</a> and found that the current version of their vaccine works just as well against the B117 variant that is now dominant in the UK. It does, however, <a href="https://www.cidrap.umn.edu/news-perspective/2021/03/astrazeneca-vaccine-doesnt-prevent-b1351-covid-early-trial">appear to be less effective</a> at preventing mild to moderate disease when facing the B1351 variant that arose in South Africa, which is also now circulating in Britain.</p>
<p>And <a href="https://www.medrxiv.org/content/10.1101/2021.04.06.21254882v1">early research</a> on the Pfizer/BioNTech vaccine – which is yet to be reviewed by other scientists – suggests that there is a small drop off in performance when facing B117 and B1351, but that overall it still works well against these. </p>
<p>However, the pressing question is how these and other vaccines will fare against the <a href="https://theconversation.com/b16172-qanda-all-you-need-to-know-about-this-sars-cov-2-variant-160903">B16172 subvariant</a> first discovered in India, which is <a href="https://theconversation.com/coronavirus-variant-b16172-could-it-block-the-uks-path-out-of-lockdown-160874">also now spreading in the UK</a>. We’re still waiting for research to definitively answer this question, though <a href="https://www.thetimes.co.uk/article/vaccines-are-nearly-as-effective-against-the-indian-variant-2rdqx5bdr">early findings</a> from a study being run by the University of Oxford suggest there’s only a small decline in the protection offered by vaccines when facing the variant.</p>
<p>We also don’t yet know whether vaccines will offer the same degree of suppression once lockdown measures have been lifted and people are mixing more freely. <a href="https://www.timesofisrael.com/active-covid-cases-in-israel-fall-below-1000-for-1st-time-since-march-2020/">Israel relaxed lockdown restrictions</a> after its successful vaccination campaign, and infections continued to decline there. However, Israel was facing the B117 variant; in the UK, it’s possible that B16172 – which <a href="https://www.bbc.co.uk/news/health-57119579">appears to be more transmissible</a> – will become dominant and be harder to suppress.</p>
<iframe src="https://ourworldindata.org/explorers/coronavirus-data-explorer?zoomToSelection=true&time=2020-12-08..latest&pickerSort=desc&pickerMetric=new_cases_smoothed_per_million&Metric=Confirmed+cases&Interval=7-day+rolling+average&Relative+to+Population=true&Align+outbreaks=false&country=USA~GBR~ISR&hideControls=true" loading="lazy" style="width: 100%; height: 600px; border: 0px none;" width="100%" height="400"></iframe>
<p>Certainly, with lockdown restrictions easing in the UK there’s the potential for an increase in transmission. However, from <a href="https://coronavirus.data.gov.uk/">existing data</a> we can see that the ratio between infections and serious illness is increasing, meaning we’re recording fewer hospitalisations or deaths per number of infections. If there is an increase in cases, it hopefully shouldn’t mean a big spike in people getting seriously ill.</p>
<p>As the UK and the rest of the world continue with their vaccination programmes, we must carry on monitoring how these COVID-19 vaccines protect people as the pandemic evolves. For now, the data suggests that vaccines have helped propel the UK into a position where reopening can take place – but we need to remain vigilant in case the situation changes.</p><img src="https://counter.theconversation.com/content/160813/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Utkarsh Agrawal 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>Research has shown that vaccines have reduced infections, disease and hospitalisations – but will they continue to do so in the face of new variants?Utkarsh Agrawal, Research Fellow in Health Data Science, University of St AndrewsLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1600722021-05-16T12:16:26Z2021-05-16T12:16:26ZIndian variant and travel bans: COVID-19 warnings should be rooted in science, not anti-South Asian racism<p>At the end of April, the Canadian government implemented a month-long travel ban to and from India and Pakistan due to COVID-19 crises both countries face and a new strain of the virus linked to India. The travel bans and new mutations have exacerbated the animosity South Asians have faced as a result of being singled out for COVID-19 outbreaks.</p>
<p>The Indian variant, <a href="https://www.theguardian.com/world/2021/may/06/new-concerns-indian-covid-variant-clusters-found-across-england-ongoing-risk-high">or B.1.617</a>, has been dubbed a “double mutant,” and data suggests that it is <a href="https://theconversation.com/whats-the-new-coronavirus-variant-in-india-and-how-should-it-change-their-covid-response-157957">more contagious than the original virus</a>. However, little is still known about the variant including if vaccines will work against it. </p>
<p>The World Health Organization (WHO) <a href="https://www.cbc.ca/news/health/who-classifies-b1617-variant-first-identified-in-india-as-global-variant-of-concern-1.6020830">designated the variant as being of concern</a>, like the mutations from the U.K., South America and South Africa. Yet the western media sensationalized the variant <a href="https://nationalpost.com/news/amid-surging-cases-and-double-mutant-variant-flights-from-india-touch-down-in-canada">as soon as it was detected.</a></p>
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<p>As the Indian variant becomes more prevalent within our borders, anti-South Asian sentiment is also growing, putting the community at a higher risk of hate crimes. </p>
<p>As a first generation South Asian Canadian and an anti-racism scholar at Carleton University, I’m interested in looking at the effects of the pandemic on the perception of minority communities. Due to the rise in hate crimes against the East Asian community, my concern is that South Asians will face the same violence but with less public support.</p>
<h2>History of anti-South Asian racism</h2>
<p>Over the past year, since the COVID-19 pandemic spread globally, there has been a <a href="https://theconversation.com/as-asian-canadian-scholars-we-must-stopasianhate-by-fighting-all-forms-of-racism-157743">rise in anti-Asian racism</a>, specifically targetting East Asian communities.</p>
<p>Tensions were exacerbated when former U.S. president Donald Trump referred to the <a href="https://www.forbes.com/sites/brucelee/2020/06/24/trump-once-again-calls-covid-19-coronavirus-the-kung-flu/">virus as the “Kung Flu” and “China Virus.”</a> In the past month, the <a href="https://www.stopasianhate.info/">#StopAsianHate</a> movement has led to wide scale social supports and a coming together of the international community.</p>
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Read more:
<a href="https://theconversation.com/the-atlanta-attacks-were-not-just-racist-and-misogynist-they-painfully-reflect-the-society-we-live-in-157389">The Atlanta attacks were not just racist and misogynist, they painfully reflect the society we live in</a>
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<p>In contrast, hate crimes against the South Asian community have been, and continue to be, largely under-reported. And when they are acknowledged, the stories quickly cycle out of the news.</p>
<p>Since South Asian people began migrating to Canada, <a href="https://www.southasiancanadianheritage.ca/march-1907/">they have been the targets of biased laws, stereotyping and violence</a>. From the <a href="https://www.cbc.ca/news/canada/british-columbia/air-india-bombing-35-years-1.5623206">Air India Bombing in 1985</a>, an event that is largely unknown by Canadians despite it being the worst mass murder in the country’s history, to the egregious acts of <a href="https://www.theglobeandmail.com/news/national/hate-crimes-rose-after-911/article1132924/">violence in the aftermath of 9/11</a>, South Asians have been left to shoulder pain and grief alone. </p>
<p>More recently, <a href="https://www.washingtonpost.com/nation/2021/04/18/sikh-indianapolis-shooting/">four Sikhs were among those murdered at a FedEx centre in in Indianapolis</a>. There has been speculation that the <a href="https://www.vox.com/2021/4/20/22392178/indianapolis-shooting-sikh-americans">shooter chose the centre because a large number of Sikhs worked there</a>. This shooting came a month after <a href="https://www.nytimes.com/live/2021/03/17/us/shooting-atlanta-acworth">six Asian women were killed in Atlanta</a>. </p>
<p>Unlike the Atlanta shooting, the Indianapolis shooting quickly disappeared from public view with very <a href="https://msmagazine.com/2021/04/24/south-asian-racism-fedex-indianapolis-sikh-shooting/">few rallying behind the Sikh community</a>. </p>
<p>This lack of public support is parallel to the silence around hate <a href="https://saalt.org/tag/hate-crimes/">crimes against South Asians since 9/11</a>. <a href="https://www.nytimes.com/2012/08/06/us/shooting-reported-at-temple-in-wisconsin.html">The Oak Creek Gurdwara shooting</a> in Wisconsin, multiple incidents of <a href="https://globalnews.ca/news/4678325/kelowna-sikh-temple-vandalized-with-racist-graffiti/">racist graffiti</a> and anti-South Asian sentiment have run rampant for the last 20 years. South Asians have had, and continue to, shoulder pain and grief of their own communities while trying to survive in a western world.</p>
<h2>Fueling fear and hate</h2>
<p>As COVID-19 cases rose across Canada, regions with large South Asian populations became targets for politicians and the public.</p>
<p>The <a href="https://www.cbc.ca/news/canada/british-columbia/covid-19-rates-in-south-asian-communities-require-nuanced-understanding-scholar-explains-1.5810591">Fraser Valley</a>, <a href="https://www.cbc.ca/news/canada/toronto/brampton-coronavirus-covid-19-south-asian-1.5723330">Peel region</a> and <a href="https://dailyhive.com/calgary/kenney-calgary-south-asian-communities-covid-19-cases">Calgary</a> were reported as being COVID-19 hotspots because of large families and super spreader events. What the media and government officials failed to acknoweldge is that immigrant communities are largely frontline workers, who had little choice but to go into work during the pandemic.</p>
<p>Cultural and religious events such as <a href="https://quickbitenews.com/article/brampton/diwali-celebrations-cause-concerns-over-next-covid-19-surge-in-brampton/">[Diwali]</a> and <a href="https://www.aljazeera.com/news/2020/4/13/anger-as-right-wing-uk-voices-suggest-ramadan-virus-spread">Ramadan</a> have been implicated in rising case numbers. </p>
<p>The media has consistently demonized immigrant populations for the high number of COVID-19 cases, without taking into account what these communities are facing. The housing market and <a href="https://www.americanprogress.org/issues/race/news/2020/04/14/483125/economic-fallout-coronavirus-people-color/">economic hardships faced by racialized people</a> forces them into situations - such as sharing homes and working in factories - <a href="https://www.newswire.ca/news-releases/cpho-sunday-edition-the-impact-of-covid-19-on-racialized-communities-877262749.html">that put them at a higher risk of contracting the virus</a>. </p>
<p>The reporting of the travel ban and Indian variant borders on irresponsible due to the <a href="https://www.nature.com/articles/d41586-021-01274-7">lack of scientific evidence</a>, as well as framing the country and those who originate there as <a href="https://www.thestar.com/opinion/contributors/2021/04/28/south-asians-are-suffering-from-covid-19-disproportionately-as-loved-ones-in-india-are-in-crisis-racializing-the-variant-opens-up-racist-scapegoating.html">potential threats.</a></p>
<p>South Asians are as frustrated and scared as the rest of Canadians. However, biased reporting only works to further marginalize individuals who are already feeling vulnerable in a time of tense race relations.</p>
<h2>Stop racially biased reporting</h2>
<p>Recently, <a href="https://www.thejuggernaut.com/whatsapp-forwards-stoke-fear-and-spread-misinformation-during-india-covid-crisis">WhatsApp messages</a> have been circulating warning Americans against interacting with South Asians. It is reminiscent of the anti-Chinese rhetoric that took place at the beginning of the pandemic. </p>
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<p>The tone with which the U.K., South American and South African variants have been reported has not spurred any hostility towards those countries and its citizens, making it difficult to not see the implicit racism. </p>
<p>South Asians are asking for the media and government officials to root their warnings in scientific evidence, not stereotypes.</p><img src="https://counter.theconversation.com/content/160072/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jasmeet Bahia 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>As the Indian variant becomes more prevalent within our borders, anti-South Asian sentiment is also growing, putting the community at a higher risk of hate crimes.Jasmeet Bahia, PhD Student, Sociology, Carleton UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1609032021-05-14T18:07:31Z2021-05-14T18:07:31ZB16172 Q&A: all you need to know about this SARS-CoV-2 variant<figure><img src="https://images.theconversation.com/files/400812/original/file-20210514-15-1ym2x2k.jpg?ixlib=rb-1.1.0&rect=242%2C0%2C5470%2C3592&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-illustration/coronavirus-pattern-3d-rendering-illustration-showing-1883895244">Raul Valcarcel Romero/Shuttterstock</a></span></figcaption></figure><p>Just as the UK is beginning to reopen, another variant of SARS-CoV-2, the virus that causes COVID-19, appears to be taking hold in the UK. The variant, which was first identified in India, is particularly prevalent in <a href="https://www.theguardian.com/world/2021/may/13/india-covid-variant-is-it-threat-uk-reopening-plans">London and the north-west</a>, leading to calls for targeted responses in certain areas.</p>
<p>There is much we still don’t know about the B16172 variant, and it’s unclear whether its emergence will significantly derail plans to lift restrictions around the country. But the prime minister, Boris Johnson, has said he is “<a href="https://news.sky.com/story/covid-19-three-types-of-indian-variant-are-in-the-uk-data-shows-12305611">anxious</a>” about the variant, and some experts are recommending a pause in the planned lifting of restrictions.</p>
<p>The Conversation asked Zania Stamataki, an expert in viral immunology, some key questions about what we know so far about B16172, and what can be done about it.</p>
<h2>What is B16172 and how is it different from other variants?</h2>
<p>The B16172 is one of three SARS-CoV-2 variants first reported in <a href="https://theconversation.com/coronavirus-variant-b16172-could-it-block-the-uks-path-out-of-lockdown-160874">India</a>. You may have heard it referred to as the “double mutant”, which makes no sense from a virology perspective (it has more than two mutations). However, this terminology was used to convey that this variant of concern may be both more transmissible and harder to neutralise by antibodies raised against previous variants. </p>
<p>The reason B16172 is causing concern in the UK is because we are recording increasing numbers of cases of this variant, which sparks suspicion about whether it is more transmissible than other viruses, including the now prevalent B117 (Kent). At a time when we are slowly lifting restrictions, it is important to understand if this variant pushes us to change course. </p>
<h2>When will we know if the vaccines work against it?</h2>
<p>Experiments in the lab currently aim to tell us if antibodies and T cells raised after vaccination are able to control infection by this variant. The key question is when we are going to get our hands on real-life data.</p>
<p>In the UK, an estimated <a href="https://www.ons.gov.uk/peoplepopulationandcommunity/healthandsocialcare/conditionsanddiseases/articles/coronaviruscovid19infectionsurveyantibodydatafortheuk/13may2021#percentage-of-adults-testing-positive-for-covid-19-antibodies-and-percentage-of-adults-vaccinated-against-covid-19-in-england-wales-northern-ireland-and-scotland">60-70%</a> of people have antibodies to SARS-CoV-2, either from natural infection or first vaccination. <a href="https://www.ons.gov.uk/peoplepopulationandcommunity/healthandsocialcare/conditionsanddiseases/articles/coronaviruscovid19infectionsurveyantibodydatafortheuk/13may2021#percentage-of-adults-testing-positive-for-covid-19-antibodies-and-percentage-of-adults-vaccinated-against-covid-19-in-england-wales-northern-ireland-and-scotland">Around 30%</a> of us have received both jabs. </p>
<p>As this variant spreads in various hotspots, such as <a href="https://www.theguardian.com/world/2021/may/14/vaccine-supply-to-covid-hotspots-in-england-must-at-least-double">Bolton and Erewash</a>, we are looking to measure any potential increase in hospitalisation or deaths. It takes two to four weeks from the onset of infection to start receiving those numbers. </p>
<h2>Should the establishment of this variant change lockdown reopening plans?</h2>
<p>Emergence of variants is natural for RNA viruses, and the UK government is right to be vigilant with surge testing and localised measures. If there is an indication that this variant bypasses vaccine defences, then our current reopening plans will be risk-assessed and re-evaluated. </p>
<p>The reason that we are in the privileged position to gradually and cautiously lift restrictions in the UK is because of our early and broad vaccination programme. Many countries in the rest of the world, such as India, currently suffer high infection rates, with <a href="https://theconversation.com/each-burning-pyre-is-an-unspeakable-screeching-horror-one-researcher-on-the-frontline-of-indias-covid-crisis-160055">devastating results</a>. These provide fertile grounds for new variants to spread. </p>
<p>If our vaccines stop working, our only option to prevent increases in mortality will be further restrictions until new vaccines are available. But, importantly, there is no indication at the moment that any variant surpasses current vaccine protection against serious COVID-19. </p>
<h2>Should we target areas with high proportions of B16172 with surge vaccination campaigns or local lockdowns?</h2>
<p>We need to get better at pouncing on localised outbreaks with strict measures to prevent new variants from taking hold and affecting our way of life. The geographically confined nature of these outbreaks lends itself to targeted restrictions. </p>
<p><a href="https://www.theguardian.com/politics/live/2021/may/14/uk-covid-live-surge-vaccinations-indian-variant-lockdown-england-coronavirus-latest-updates">Surge vaccinations</a> in affected areas are a great idea – please bear in mind, however, that it takes around two weeks after a jab to build an immune response. </p>
<p>Small, localised lockdowns targeting affected schools, businesses, neighbourhoods or towns have the power to control spread immediately and extinguish new outbreaks before they get out of control. </p>
<p>Rapid sharing of <a href="https://www.gov.uk/government/publications/covid-19-variants-genomically-confirmed-case-numbers/variants-distribution-of-cases-data">information</a> on new outbreaks is also important, so people in affected areas can change their travel and social plans until it’s safe to resume normal operations. With our cooperation, localised restrictions should last a matter of weeks, helping everyone return to life as normal quickly and safely.</p><img src="https://counter.theconversation.com/content/160903/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Zania Stamataki collaborates with UKRI-funded groups to investigate neutralisation responses to SARS-CoV-2 variants, using fully replicating virus in containment level 3 laboratories at the University of Birmingham, UK. </span></em></p>A viral immunologist answers key questions about the B16172 variant.Zania Stamataki, Senior Lecturer in Viral Immunology, University of BirminghamLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1605642021-05-13T17:09:05Z2021-05-13T17:09:05ZCOVID vaccine weekly: local lockdowns and vaccination surges could be used to contain B16172 variant<p>May 17 is probably circled and underlined in many British people’s diaries. It marks a key point in the UK’s exit from lockdown: from this date, six people or two households can mix indoors, indoor drinking and dining can resume, and people can stay overnight at other people’s houses.</p>
<p>But there’s a problem. B16172, a subtype of the coronavirus variant currently sweeping through India, is taking hold in some parts of the UK. The government has labelled it a <a href="https://www.reuters.com/world/uk/public-health-england-says-coronavirus-variant-b16172-is-variant-concern-2021-05-07/">“variant of concern”</a>, as it appears to be spreading quickly. There are worries it could gain a much stronger foothold as Britain reopens. </p>
<p>For now, the government is sticking to its lockdown roadmap, meaning restrictions will still ease on May 17. However, the prime minister hasn’t ruled out using <a href="https://www.telegraph.co.uk/global-health/science-and-disease/coronavirus-news-covid-inquiry-vaccines-india-variant-pfizer/">local lockdowns</a> or <a href="https://www.bbc.co.uk/news/uk-57102392">locally targeted vaccination surges</a> to keep the variant under control. </p>
<p>In the meantime, we need to be careful, <a href="https://theconversation.com/coronavirus-variant-b16172-could-it-block-the-uks-path-out-of-lockdown-160874">says</a> Deborah Dunn-Walters, professor of immunology at the University of Surrey. Early indications are that B16172 is more transmissible than B117, the so-called Kent variant that plagued the UK over winter, and we don’t yet know if it causes more severe disease or exactly how effective it is at evading vaccine-induced immunity. Certainly, anyone waiting for their second vaccine dose should make sure they take it, to ensure they have the greatest possible protection.</p>
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<p><em><strong>This is our weekly round-up of expert information about the <a href="https://theconversation.com/uk/topics/covid-vaccines-96571">COVID-19 vaccines</a>.</strong> <br>
The Conversation, a not-for-profit group, works with a wide range of academics across its global network to produce evidence-based analysis and insights. Get more regular updates from trusted experts by <a href="https://theconversation.com/uk/newsletters/the-daily-2">subscribing to our free newsletter</a> .</em></p>
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<p>Meanwhile, India’s attempts to get on top of this new variant by increasing vaccination are faltering. In the <a href="https://theconversation.com/why-indias-covid-19-vaccine-rollout-is-faltering-podcast-160800">latest episode</a> of The Conversation Weekly podcast, a panel of experts looks at why rollout there remains sluggish, despite the pressing need to speed things up. </p>
<p>By early May, just over 2% of India’s population had been fully vaccinated against COVID-19. Largely this has been down to a <a href="https://theconversation.com/charging-indians-for-covid-vaccines-is-bad-letting-vaccine-producers-charge-what-they-like-is-unconscionable-160529">shortage of supply</a>, with a major cause being India’s decision to approve only two Indian-made vaccines for use, meaning leading products such as the Pfizer vaccine are unavailable. Among those who don’t get the vaccine for free – which is everyone under 45 who isn’t a health worker – affordability is now a major issue for many. </p>
<p>In the coming weeks, vaccine passports (certificates that confirm someone has been vaccinated for COVID-19) are likely to be introduced in the UK. It’s not clear how they’ll be used – whether solely for international travel or more broadly to grant people access to restaurants, pubs, bars and other public venues inside the UK – but it’s fair to say they aren’t popular.</p>
<p>But that doesn’t mean they aren’t good for society. These passports are a minimal cost for returning to normal daily life and for reducing anxiety for those you come into contact with, <a href="https://theconversation.com/vaccine-passports-why-they-are-good-for-society-160419">argue</a> Barbara Jacquelyn Sahakian, Christelle Langley and Julian Savulescu. This makes them just a small sacrifice for the greater good.</p>
<p>Finally, while the UK’s vaccine rollout has been a marked success, it isn’t the only European country to have moved quickly. Serbia has managed to fully vaccinate a quarter of its population, despite not having the same vaccine-purchasing power as bigger, richer countries. It’s capitalised on its good relations with both the east and west to secure a diverse portfolio of doses from the UK, US Russia and China, <a href="https://theconversation.com/small-countries-and-covid-19-vaccination-the-example-of-serbia-157159">says</a> Jovana Stanisljevic of the Grenoble École de Management.</p>
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<p><em>Get the latest news and advice on <a href="https://theconversation.com/uk/covid-19">COVID-19</a>, direct from the experts in your inbox. Join hundreds of thousands who trust experts by <strong><a href="https://theconversation.com/uk/newsletters/the-daily-2">subscribing to our newsletter</a></strong>.</em></p><img src="https://counter.theconversation.com/content/160564/count.gif" alt="The Conversation" width="1" height="1" />
The B16172 variant of concern risks spreading in the UK when restrictions on indoor socialising ease on May 17.Rob Reddick, Commissioning Editor, COVID-19Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1608742021-05-13T11:50:49Z2021-05-13T11:50:49ZCoronavirus variant B16172: could it block the UK’s path out of lockdown?<p>A few weeks of relief from isolation, huddling in your big coats outside chatting to a few friends in the evening after work, beginning to feel optimistic about the roadmap out of lockdown, and then another curveball comes in. This time in the form of the coronavirus variant called B1617 – which was first identified in India. Or rather, to be specific, B16172, because B16171 and B16273 have not shown such an alarming increase in cases. </p>
<p>The <a href="https://www.telegraph.co.uk/news/2021/05/12/fast-spreading-indian-variant-main-strain-englands-virus-hotspots/">rapid increase</a> in the proportion of SARS-CoV-2 sequences in England that are B16172 seem to indicate that its transmissibility exceeds even that of the B117 variant (the so-called Kent variant), which kept the UK in lockdown over the winter. </p>
<p>An initial feeling of unease, given the dreadful situation that has <a href="https://theconversation.com/covid-19-in-india-an-unfolding-humanitarian-crisis-159654">unfolded in India</a>, has given way to genuine concern that this could be the problem that blocks the UK’s path out of lockdown. This would, of course, be a tremendous disappointment to a country that has been looking forward to a summer of freedom. </p>
<p>So perhaps us scientists shouldn’t say anything until we are more sure whether it could be a problem. But the consequences of not saying anything if it does turn out to be a valid concern could be catastrophic, and there may not be much time to act. </p>
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<p>If it turns out not to be a problem, then holding our hands up to say: “Sorry, I was wrong,” is easy. What we need to know now is whether immunity imparted by the vaccines works against it. There is very little data on this, certainly not for the B16172 variant. </p>
<p>Very early indications are that there is <a href="https://www.nature.com/articles/d41586-021-01274-7">some decrease in immunity</a> for B16171, but perhaps not as much of a decrease as B1351 (the variant first identified in South Africa) has shown. However, data hasn’t always distinguished between the three different B1617 variants, and B16172 has unique mutations that are of concern, so we need more information to be sure. We also need to check whether this variant might be associated with an increase in the severity of disease. Being cautious about our risks in the meantime is sensible.</p>
<h2>It’s a spectrum</h2>
<p>Escape from immunity is not all or nothing. Our immune system makes a massively diverse repertoire of antibodies and would never make just one antibody against the virus. So, while a mutation in the virus could result in some of our antibodies not binding to it (to block its activity), there would still be others that could bind to it.</p>
<p>Each of us is unique, as are our immune systems, so we all make a slightly different response to the vaccine. If we have a very healthy immune system that makes a lot of different antibodies in the first place, then losing the use of a few would still leave us with protection. </p>
<p>On the other hand, if we were unlucky enough to not have many antibodies of the appropriate type in the first instance, then losing the use of some might have more serious consequences. </p>
<p>On a population level, this means that the proportion of people that are protected by the COVID vaccines might decrease against a new variant. Until we have more data, though, we won’t know how much of a problem this will be. In the meantime, many people are <a href="https://theconversation.com/qanda-with-sharon-peacock-coronavirus-variant-hunter-154808">keeping a close eye on the situation</a>. There are also a lot of people working very hard to roll out vaccines. Please take advantage of this and make sure you get both doses.</p><img src="https://counter.theconversation.com/content/160874/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Deborah Dunn-Walters receives funding from UKRI and is Professor of Immunology at the University of Surrey. She is also a Trustee for the Dunhill Medical Trust and The British Society for Immunology (BSI). She chairs the BSI COVID-19 Immunology Taskforce.</span></em></p>There’s still a lot we don’t know about the latest variant of concern: B16172.Deborah Dunn-Walters, Professor of Immunology, University of SurreyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1603452021-05-07T00:54:46Z2021-05-07T00:54:46ZWhat’s the Valneva COVID-19 vaccine, the French shot that’s supposed to be ‘variant proof’?<figure><img src="https://images.theconversation.com/files/399120/original/file-20210506-14-ssjrin.jpg?ixlib=rb-1.1.0&rect=0%2C4%2C1000%2C658&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/valneva-covid19-vaccine-concept-finger-pointing-1950918379">mundissima/www.shutterstock.com</a></span></figcaption></figure><p>A COVID-19 vaccine from French company Valneva has yet to complete clinical trials. But it has <a href="https://www.news.com.au/national/australia-in-talks-with-french-firm-valneva-about-importing-vaccine/news-story/bcd4d56629b5469311b1d9a5db6edcc3">caught the eye</a> of governments in the UK, <a href="https://twitter.com/ReutersWorld/status/1388201550938529799">Europe</a> and Australia. </p>
<p>One of the vaccine’s main selling points is its apparent ability to mount a more general immune response against SARS-CoV-2, the virus that causes COVID-19, rather than rely on the <a href="https://theconversation.com/revealed-the-protein-spike-that-lets-the-2019-ncov-coronavirus-pierce-and-invade-human-cells-132183">spike protein</a> to do this.</p>
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<p>This means the vaccine is more likely to be effective against the type of virus variants we’ve already seen emerging, and may emerge in the future. <a href="https://www.scmp.com/news/world/europe/article/3131661/french-firms-more-variant-proof-coronavirus-vaccine-could-help">Some reports</a> describe it as “<a href="https://medium.com/technicity/phase-3-trials-on-a-new-variant-proof-vaccine-begin-9f52225e7350">variant proof</a>”. </p>
<p>The hope is vaccines using this technology would be able to provide protection for longer, rather than keep being reformulated to get ahead of these new variants.</p>
<h2>How does it work?</h2>
<p>Valneva’s vaccine, called VLA2001, is based on tried and tested vaccine technology. It’s the technology used in the vaccine against <a href="https://www.jstor.org/stable/24858956">poliovirus</a> and in some types of <a href="https://www.cdc.gov/flu/prevent/quadrivalent.htm">flu vaccines</a>. And the company already has a commercially available <a href="https://preventje.com/hcp/what-is-ixiaro/">Japanese encephalitis</a> vaccine based on the same technology.</p>
<p>VLA2001 uses an <a href="https://www.who.int/news-room/feature-stories/detail/the-race-for-a-covid-19-vaccine-explained">inactivated version of the whole virus</a>, which cannot replicate or cause disease.</p>
<p>The virus is inactivated using a chemical called <a href="https://pubchem.ncbi.nlm.nih.gov/compound/beta-Propiolactone">beta-propiolactone or BPL</a>. This is <a href="https://www.tandfonline.com/doi/full/10.1586/erv.12.38">widely used</a> to inactivate other viruses for vaccines. It was even used to make <a href="https://www.liebertpub.com/doi/full/10.1089/vim.2010.0028?casa_token=jNYegUijdDkAAAAA%3AQfR_VQ4OjQeI70ajPwgEZb_2lWASqd2Mm5xMcj9aDKYOS0FFAB344DzrqW7g-lmaTeKDW-T8oJI">experimental versions</a> of vaccines against SARS-CoV, the virus that caused <a href="https://www.cdc.gov/sars/about/fs-sars.html">SARS (severe acute respiratory syndrome)</a>.</p>
<p>This type of inactivation is expected to preserve the structure of the viral proteins, as they would occur in nature. This means the immune system will be presented with something similar to what occurs naturally, and mount a strong immune response.</p>
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Read more:
<a href="https://theconversation.com/from-adenoviruses-to-rna-the-pros-and-cons-of-different-covid-vaccine-technologies-145454">From adenoviruses to RNA: the pros and cons of different COVID vaccine technologies</a>
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<p>After being inactivated, the vaccine would be highly purified. Then, an adjuvant (an immune stimulant) is added to induce a strong immune response.</p>
<p>VLA2001 isn’t the first inactivated vaccine against COVID-19. Leading COVID-19 inactivated vaccines, such as those developed by Sinopharm and Bharat Biotech, have been <a href="https://www.nytimes.com/interactive/2020/science/coronavirus-vaccine-tracker.html">approved for use</a> in China and received emergency approval in other countries, including India.</p>
<p>However, VLA2001 is the only COVID-19 vaccine candidate using whole inactivated virus in clinical trials in the UK and in mainland Europe.</p>
<h2>What are the benefits we know so far?</h2>
<p>This approach to vaccine development presents the immune system with all of the structural components of the SARS-CoV-2 virus, not just the spike protein, as many other COVID-19 vaccines do. </p>
<p>So Valneva’s vaccine is thought to produce a more broadly protective immune response. That is, antibodies and cells of the immune system are able to recognise and neutralise more pieces of the virus than just the spike protein. </p>
<p>As a result, Valneva’s vaccine could be more effective at tackling emerging COVID-19 virus variants and, if approved, play a useful role as a booster vaccine. </p>
<p>Valneva’s vaccine can be stored at <a href="https://valneva.com/research-development/covid-19-vla2001/">standard cold-chain conditions (2-8°C)</a> and is expected to be given as two shots.</p>
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Read more:
<a href="https://theconversation.com/uk-south-african-brazilian-a-virologist-explains-each-covid-variant-and-what-they-mean-for-the-pandemic-154547">UK, South African, Brazilian: a virologist explains each COVID variant and what they mean for the pandemic</a>
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<h2>How about results from clinical trials?</h2>
<p><a href="https://clinicaltrials.gov/ct2/show/NCT04671017?term=valneva&draw=3&rank=5">According to</a> <a href="https://valneva.com/press-release/valneva-reports-positive-phase-1-2-data-for-its-inactivated-adjuvanted-covid-19-vaccine-candidate-vla2001/">the company</a>, no safety concerns or serious adverse events were associated with VLA2001 in early-stage clinical trials. </p>
<p>VLA2001 was given as a low, medium or high dose in these trials with <a href="https://clinicaltrials.gov/ct2/show/NCT04671017?term=valneva&draw=3&rank=5">all participants</a> in the high-dose group generating antibodies to the virus spike protein. </p>
<p>One measure of immune response in the high-dose group after completing the two doses indicated antibody levels were, after two weeks, at least as high as those seen in patients naturally infected with SARS-CoV-2.</p>
<p>Interestingly, VLA2001 induced immune responses against a number of virus proteins (including the spike protein) across all participants, an encouraging sign the vaccine can provide broad protection against COVID-19.</p>
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<p>The vaccine has since advanced to <a href="https://valneva.com/press-release/valneva-initiates-phase-3-clinical-trial-for-its-inactivated-adjuvanted-covid-19-vaccine-candidate-vla2001/">phase 3 clinical trials</a> in the UK. The trial, which started in April 2021, will compare its safety and efficacy <a href="https://www.globenewswire.com/news-release/2021/04/21/2214528/0/en/Valneva-Initiates-Phase-3-Clinical-Trial-for-its-Inactivated-Adjuvanted-COVID-19-Vaccine-Candidate-VLA2001.html">with the AstraZeneca vaccine</a>. </p>
<p>The phase 3 trial is expected to be completed by the northern hemisphere’s <a href="https://www.bloomberg.com/news/articles/2021-04-29/a-french-biotech-says-inactivated-vaccines-are-the-way-to-fight-covid-variants">autumn this year</a>. And if successful, would be submitted for regulatory approval after that.</p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/a-single-vaccine-to-beat-all-coronaviruses-sounds-impossible-but-scientists-are-already-working-on-one-156373">A single vaccine to beat all coronaviruses sounds impossible. But scientists are already working on one</a>
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<h2>Who’s interested?</h2>
<p>Despite phase 3 clinical trials only just starting, the UK government has <a href="https://www.news.com.au/national/australia-in-talks-with-french-firm-valneva-about-importing-vaccine/news-story/bcd4d56629b5469311b1d9a5db6edcc3">pre-ordered</a> more than <a href="https://valneva.com/press-release/valneva-announces-uk-government-exercise-of-option-for-40-million-doses-of-its-inactivated-adjuvanted-covid-19-vaccine/">100 million doses</a> of the vaccine from Valneva, with the option of buying more down the track. If trials prove successful and pass regulatory approval, this means the vaccine could be used as a booster in time for this year’s northern hemisphere’s winter.</p>
<p>Australia <a href="https://www.news.com.au/national/australia-in-talks-with-french-firm-valneva-about-importing-vaccine/news-story/bcd4d56629b5469311b1d9a5db6edcc3">has confirmed</a> it’s also in talks with Valeneva about importing the vaccine. Some countries in Europe are also <a href="https://www.reuters.com/world/europe/exclusive-some-eu-nations-still-want-valneva-covid-19-vaccine-deal-sources-2021-04-30/?taid=608c4f0e12d1d500012373d2&utm_campaign=trueAnthem:+Trending+Content&utm_medium=trueAnthem&utm_source=twitter">reportedly keen</a> to strike a deal.</p>
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<p>As new cases of COVID-19 increase globally, we’ll continue to see new viral variants emerge that threaten to escape the protection existing vaccines offer.</p>
<p>Already, we are seeing vaccines from companies <a href="https://www.theguardian.com/world/2021/may/05/tweaked-moderna-vaccine-neutralises-covid-variants-in-trials">such as</a> <a href="https://investors.modernatx.com/news-releases/news-release-details/moderna-announces-positive-initial-booster-data-against-sars-cov">Moderna</a> and <a href="https://www.wsj.com/articles/covid-19-vaccines-targeting-multiple-strains-are-in-the-works-11615374007">Novavax</a> begin to reformulate their spike protein-based vaccines to get ahead of emerging variants.</p>
<p>So Valneva’s vaccine, with the potential to elicit a more broadly protective immune response, may prove to be a useful tool to combat the rise of the virus and its mutations. However, whether the vaccine is really “variant proof” or merely less affected by emerging variants remains to be seen.</p><img src="https://counter.theconversation.com/content/160345/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Adam Taylor receives funding from the Australian National Health and Medical Research Council. </span></em></p>It sounds too good to be true, a vaccine that can protect against future virus variants. But governments around the world are keen to learn more.Adam Taylor, Early Career Research Leader, Emerging Viruses, Inflammation and Therapeutics Group, Menzies Health Institute Queensland, Griffith UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1566732021-05-05T12:33:02Z2021-05-05T12:33:02ZCan scientists predict all of the ways the coronavirus will evolve?<p>Late last year, <a href="https://www.bbc.com/future/article/20210127-covid-19-variants-how-mutations-are-changing-the-pandemic">three distinct</a> and fast-spreading coronavirus variants were observed in the UK, South Africa and Brazil. More recently, variants in <a href="https://theconversation.com/q-a-indian-coronavirus-variant-what-is-it-and-what-effect-will-it-have-159269">India</a>, <a href="https://www.nature.com/articles/d41586-021-00564-4">the US</a> <a href="https://www.cnbc.com/2021/05/03/who-is-closely-monitoring-10-covid-variants-as-virus-mutates-around-the-world-.html">and elsewhere</a> are causing alarm. Does the emergence of these variants portend a protracted battle with the pandemic, or will the virus soon run out of evolutionary room to manoeuvre and settle down as a more benign, endemic pathogen? </p>
<p>Predictions about the evolutionary course of the virus, and specifically changes in virulence, will always be riddled with uncertainty. The vagaries of randomly mutating RNA, chaotic patterns of transmission and expansion, and partially understood forces of natural selection, present challenges to even the most insightful evolutionary soothsayer. Nevertheless, established evolutionary concepts, combined with a wealth of data from the virus itself, can at least provide some pointers.</p>
<p>SARS-CoV-2, the virus that causes COVID-19, jumped into humans from an unidentified animal host, and in doing so entered a new evolutionary space full of obstacles, threats, dead ends, and – very occasionally – opportunity. This space is difficult to imagine and measure. It is annoyingly multidimensional and its boundaries and topographies can be viewed from many esoteric vantages. </p>
<p>An unsophisticated entry point is to consider the upper limits to genome sequence diversity, or the boundaries of mutational space. Assume the SARS-CoV-2 genome is 30,000 sites long, each of which can be occupied by one of four bases (adenine, cytosine, guanine and uracil). It follows there are over a quintillion (four to the power 30) possible genome sequences, roughly equivalent to the width of the Milky Way in metres. </p>
<p><strong>DNA and RNA both comprise just four bases</strong></p>
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<img alt="DNA and RNA shown next to each other." src="https://images.theconversation.com/files/398898/original/file-20210505-23-4eae6z.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/398898/original/file-20210505-23-4eae6z.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/398898/original/file-20210505-23-4eae6z.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/398898/original/file-20210505-23-4eae6z.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/398898/original/file-20210505-23-4eae6z.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/398898/original/file-20210505-23-4eae6z.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/398898/original/file-20210505-23-4eae6z.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&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">DNA and RNA is made up of four bases.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-vector/structure-dna-rna-molecules-deoxyribonucleic-acid-1608843919">Ody Stocker/Shutterstock</a></span>
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<p>But this mathematical limit takes no account of biology and as such is completely unhelpful. Hardly any of these hypothetical genomes would encode a virus that is able to infect and replicate. This basic requirement to maintain the viral machinery in top working order is good news. Evolutionary constraints to maintain viral function will limit how quickly and how well the virus will adapt. </p>
<p>There is more good news. Much of the expert commentary regarding the threat from mutations in the SARS-CoV-2 genome has been <a href="https://www.nature.com/articles/s41564-020-0690-4">relatively sanguine</a>, a reflection of the fact that the vast majority of mutations in the genome have little or no functional consequence. While there may be vast tracts of mutational space that the virus could explore in theory, almost all of this space will be off-limits for a functional virus. And much of the rest will have little relevance to how the virus behaves.</p>
<p>But while mutations are mostly harmless, there remain hidden in deep mutational space, like microscopic dots on microscopic dots, very rare genomic changes that allow the virus to innovate. </p>
<h2>How fast is SARS-CoV-2 evolving?</h2>
<p>Whole-genome sequencing has provided us with a means to witness the exploration of SARS-CoV-2 through mutational space in exquisite detail. We know that the genome acquires <a href="https://theconversation.com/qanda-with-sharon-peacock-coronavirus-variant-hunter-154808">one or two mutations a month</a> on average, which, taking genome size into account, is a rate about four times slower than the flu virus. This was also widely interpreted as good news. The logic here is that a more stable genome provides fewer opportunities for the virus to escape the vaccines or pull off some other genetic trick. </p>
<p>The emergence of the “UK variant” (aka “Kent variant”, B117 or 20I/501Y.V1) was remarkable and sobering. Genome sequence data revealed that it had <a href="https://www.who.int/csr/don/31-december-2020-sars-cov2-variants/en/">picked up 23 mutations</a> (a whole years’ worth) seemingly all in one go. Most of these mutations are of little evolutionary relevance, but others are responsible for the increased rate of spread of this variant. </p>
<p>Why and how did this happen? The virus mutates during replication inside a human host. These mutations can change the way the virus interacts with human cells, including the immune system. The UK variant may have emerged during the course of a long-term infection in a single immune-compromised patient. Over many weeks, <a href="https://virological.org/t/preliminary-genomic-characterisation-of-an-emergent-sars-cov-2-lineage-in-the-uk-defined-by-a-novel-set-of-spike-mutations/563">treatment with convalescent plasma</a> – which is laden with antibodies – could have resulted in natural selection singling out this variant.</p>
<p>Other similar bursts of evolution have been observed. A recently emerged “variant of interest” has arisen in Tanzania that has <a href="https://www.medrxiv.org/content/10.1101/2021.03.30.21254323v1">34 separate mutations</a>. And examples of recombination, where different SARS-CoV-2 genomes combine to form a hybrid, <a href="https://virological.org/t/recombinant-sars-cov-2-genomes-involving-lineage-b-1-1-7-in-the-uk/658">have also been observed</a>. While these events may be rare, their potential evolutionary significance should not be downplayed. A relatively slow average mutation rate does not automatically correspond to a slow evolutionary rate.</p>
<h2>Many are called but few are chosen</h2>
<p>The spark for the emergence of the UK variant was probably evolutionary pressure to protect the virus from therapeutic antibodies (convalescent plasma). The most obvious consequence of this was an increased propensity to spread between hosts. This shows that the same mutations can provide the virus with multiple advantages simultaneously, a phenomenon known as “pleiotropy”.</p>
<p>While we may not fully understand the biological mechanisms, we can easily identify candidate mutations from the genome sequence data, because they have <a href="https://www.medrxiv.org/content/medrxiv/early/2021/03/10/2021.02.23.21252268.full.pdf">emerged over and over again</a> during the course of the pandemic. Although mutation itself is a blind process, natural selection has repeatedly picked these same mutations. This is known as “evolutionary convergence”.</p>
<p>These dozen or so mutations, in various combinations, are the defining feature of all variants. All alter the spike protein – the part of the virus that binds to human cells. Despite the increased caseload and death resulting from these mutations, can we at least take cold comfort from the fact that the total number of such mutations <a href="https://www.scientificamerican.com/article/the-coronavirus-variants-dont-seem-to-be-highly-variable-so-far/">appears to be limited</a>?</p>
<p>Perhaps. But the properties of the virus are probably not determined by single mutations in isolation, but in how several mutations interact. This combinatorial perspective suddenly opens up new zones of potentially fruitful mutational space for the virus.</p>
<p>Appreciating how single rare events can alter the trajectory of the whole pandemic alerts us to the dangers of uncontrolled spread. Just as the chances of winning the lottery increase with more tickets bought, so the likelihood of rare evolutionary events leading to new variants of concern will increase as greater numbers of people are infected. </p>
<p>New variants are no respecter of national borders and, regardless of how difficult it may be to predict evolutionary changes, one thing is clear: from an evolutionary perspective, it is imperative to keep global case numbers as low as possible.</p><img src="https://counter.theconversation.com/content/156673/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Ed Feil 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>Coronavirus is 30,000 RNA ‘letters’ long, meaning there are over a quintillion possible genome permutations.Ed Feil, Professor of Microbial Evolution at The Milner Centre for Evolution, University of BathLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1594592021-04-22T19:20:13Z2021-04-22T19:20:13ZCOVID vaccine weekly: UK closes its borders to India to safeguard effects of vaccination<p>This week the UK passed the milestone of having given <a href="https://coronavirus.data.gov.uk/details/vaccinations">10 million people</a> a second COVID-19 vaccine dose. This means that over 20% of UK adults are now fully vaccinated against the coronavirus. </p>
<p>The effects are <a href="https://www.ft.com/content/d71729a3-72e8-490c-bd7e-757027f9b226">beginning to show</a>. COVID-19 cases, hospitalisations and deaths have fallen drastically as vaccine coverage has ramped up. But importantly, rates for all of these measures have declined more steeply among older age groups where the majority are fully vaccinated. This shows Britain’s improvement isn’t just down to lockdown. </p>
<p>Politicians moved this week to protect these gains. After initial success in controlling the virus, India has seen cases soar again, and in response, the UK government added the country to its “red list”, essentially banning travel there. The concern is not just about case numbers, but also a variant of the virus now taking hold in India: B1617. </p>
<p>This variant is a double mutant, <a href="https://theconversation.com/q-a-indian-coronavirus-variant-what-is-it-and-what-effect-will-it-have-159269">explains</a> Grace Roberts, research fellow in virology at Queen’s University Belfast. Both of the key mutations it carries are thought to have the potential to make it less susceptible to vaccination. One of them may also make it more transmissible than early forms of the virus.</p>
<p>Rajib Dasgupta of Jawaharlal Nehru University <a href="https://theconversation.com/after-early-success-indias-daily-covid-infections-have-surpassed-the-us-and-brazil-why-158783">asks whether</a> B1617 is behind India’s surge in cases. Possibly, but there may be a number of factors at play. It appears B117, the much more transmissible “Kent” variant that drove the UK’s second wave, has also hit India. Public negligence and poor sanitation are also suspected of driving infections.</p>
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<img alt="" src="https://images.theconversation.com/files/320716/original/file-20200316-18073-ruhw8b.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/320716/original/file-20200316-18073-ruhw8b.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/320716/original/file-20200316-18073-ruhw8b.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/320716/original/file-20200316-18073-ruhw8b.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/320716/original/file-20200316-18073-ruhw8b.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/320716/original/file-20200316-18073-ruhw8b.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/320716/original/file-20200316-18073-ruhw8b.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p><em><strong>This is our weekly round-up of expert information about the <a href="https://theconversation.com/uk/topics/covid-vaccines-96571">COVID-19 vaccines</a>.</strong> <br>
The Conversation, a not-for-profit group, works with a wide range of academics across its global network to produce evidence-based analysis and insights. Get more regular updates from trusted experts by <a href="https://theconversation.com/uk/newsletters/the-daily-2">subscribing to our free newsletter</a> .</em></p>
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<p>In the face of countries struggling to control new outbreaks, surveying suggests that in places such as the UK where large quantities of vaccines have been ordered, the majority of people <a href="https://theconversation.com/most-people-support-sharing-vaccines-with-other-countries-new-study-159109">would support</a> redistributing some doses. The public favour reallocation based on need, followed by inability to afford vaccination. There’s less support, though, for prioritising countries that developed the COVID-19 vaccines. </p>
<p>Meanwhile, with production capacity limited and safety restrictions being introduced for certain vaccines, some countries are looking to an alternative: Russia’s Sputnik V vaccine. As Liz Breen and Sarah Schiffling <a href="https://theconversation.com/russian-covid-vaccine-why-more-and-more-countries-are-turning-to-sputnik-v-159158">write</a>, there’s a case for diversifying supply given that most supply chains are experiencing difficulties. The vaccine is affordable too. However, in the EU the European Medicines Agency has yet to approve the Russian vaccine.</p>
<p>A lack of appetite for the AstraZeneca vaccine in particular in driving this hunt for alternatives. However, while a link between it and several forms of rare blood clots has been deemed likely by European and British health authorities, reaching a definite conclusion on what risk it poses will be very difficult, <a href="https://theconversation.com/why-calculating-the-risk-of-the-astrazeneca-vaccine-is-so-difficult-a-doctor-explains-159293">writes</a> JJ Coughlan of the RCSI University of Medicine and Health Sciences. </p>
<p>Estimates of how frequently these blood clots occur under normal circumstances are uncertain, and the underlying risk of people developing clots regardless of whether they’re vaccinated might not be even across the population. Distribution of the vaccine has also been uneven – certain people are more likely to have had it – and together this makes comparing the relative risk difficult. More time and probably a lot more data will be needed to get a definitive answer on its safety.</p>
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<p><em>Get the latest news and advice on <a href="https://theconversation.com/uk/covid-19">COVID-19</a>, direct from the experts in your inbox. Join hundreds of thousands who trust experts by <strong><a href="https://theconversation.com/uk/newsletters/the-daily-2">subscribing to our newsletter</a></strong>.</em></p><img src="https://counter.theconversation.com/content/159459/count.gif" alt="The Conversation" width="1" height="1" />
Britain moves to protect itself from the B1617 variant, which vaccines may be less effective against.Rob Reddick, Commissioning Editor, COVID-19Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1592692021-04-20T14:53:38Z2021-04-20T14:53:38ZQ+A: Indian coronavirus variant – what is it and what effect will it have?<p>British prime minister Boris Johnson has cancelled his trip to India, with the country being added to the UK’s <a href="https://www.bbc.co.uk/news/uk-56806103">“red list”</a> of restricted destinations. COVID-19 cases in India are rising sharply and a specific variant of the virus – B1617 – is becoming increasingly common there. </p>
<p>B1617 has also been found outside of India, including in the UK. Cases in Britain appear to be <a href="https://inews.co.uk/news/health/indian-variant-cases-new-covid-strain-uk-figures-latest-news-963434">doubling each week</a>: there are currently 182 in the UK, up from 77 the week before. Right now the variant is “under investigation”, but unlike the Kent (B117), South African (1351) and Brazilian (P1) variants hasn’t <a href="https://www.reuters.com/world/india/britain-is-investigating-variant-originating-india-2021-04-18/">been designated</a> a “variant of concern”. </p>
<p>Does this mean this variant is different from the others and we need not be worried? Here’s what we know about its effects so far.</p>
<h2>Is this variant more infectious?</h2>
<p>We think this variant may be able to spread more easily than earlier forms of the virus. This is because of a mutation it carries called L452R, which affects the virus’s <a href="https://theconversation.com/new-coronavirus-variant-what-is-the-spike-protein-and-why-are-mutations-on-it-important-152463">spike protein</a>. This is the “key” the coronavirus uses to unlock our cells.</p>
<p>The L452R mutation changes the part of the spike protein that directly interacts with <a href="https://theconversation.com/ace2-the-molecule-that-helps-coronavirus-invade-your-cells-138369">ACE2</a>, the molecule on the surface of our cells that the virus binds with to get inside. <a href="https://www.medrxiv.org/content/10.1101/2021.03.07.21252647v1">Early research</a> – yet to be reviewed by other scientists – suggests the L452R mutation allows the virus to bind to cells more stably. In previous variants, such as the Kent variant, mutations like this that enhanced the virus’s binding ability resulted in it becoming more infectious. </p>
<p>The B1427 variant detected in California contains the same L452R mutation a B1617. It is <a href="https://www.cdc.gov/coronavirus/2019-ncov/cases-updates/variant-surveillance/variant-info.html#Concern">estimated</a> to be around 20% more transmissible than the earlier form of the coronavirus that was circulating during the first wave.</p>
<h2>And is it more dangerous?</h2>
<p>Mutations such as L452R that help with binding don’t necessarily result in more severe disease or make the virus more deadly. For example, while the B1427 variant appears to spread more easily, <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7941666/">preliminary research</a> didn’t find that it was associated with more severe infections or higher viral loads. The same could apply to B1617, though this still needs to be investigated.</p>
<p>But a particular concern is the impact B1617 may have on vaccine efficacy. The vast majority of vaccines developed against the coronavirus are based on targeting the spike protein. As the protein is on the outer surface of the virus, this is what your immune system will predominantly “see” during an infection and therefore make effective antibodies against. If mutations change the spike protein’s shape, then these antibodies may become less effective.</p>
<p>Indeed, <a href="https://www.biorxiv.org/content/10.1101/2021.04.02.438288v1">preliminary</a> <a href="https://pubmed.ncbi.nlm.nih.gov/33821281/">studies</a> suggest the L452R mutation could help the virus <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7366990/">evade the immune system</a>. On top of this, B1617 carries a second mutation, called E484Q, that changes the spike protein as well. Research suggests that mutations like it (that affect the same area of the spike protein) may also make the virus <a href="https://www.cell.com/cell-host-microbe/pdf/S1931-3128(21)00082-2.pdf">less susceptible</a> to pre-existing antibodies.</p>
<p>Early, <a href="https://www.biorxiv.org/content/10.1101/2021.04.03.438113v1">unreviewed studies</a> of these mutations’ effects in B1617 suggest that they do make the variant less susceptible to antibodies generated previously. However, it is important to stress that these findings have only been shown in laboratory experiments and not in actual people.</p>
<h2>How worried should we be?</h2>
<p>The Indian health ministry <a href="https://www.bbc.co.uk/news/world-asia-india-56507988">has stated</a> that the country’s rise in cases is not linked to these mutations, as B1617’s mutations haven’t been detected in high enough quantities to determine whether it is directly responsible. However, this may be due to lack of data, and many experts have stressed the importance of increasing virus sequencing to get a better picture.</p>
<p>It’s still too early to tell if this variant will pose a significant threat to efforts to control the virus. However, as always with public health, prevention is better than a cure. Hence, we should continue our efforts to control the virus, both in terms of regulations – masks, social distancing and so on – as well as vaccination, mass testing and genome sequencing. By continuing to combat the virus in general, we can restrict any impact this variant has.</p>
<p>The biggest cause for concern would be if B1617 undermined vaccination efforts. If this variant is able to cause disease in vaccinated individuals, it poses the risk of creating large-scale outbreaks around the world in the future.</p>
<p>Work to create booster vaccinations to deal with current and future variants is <a href="https://www.theguardian.com/world/2021/mar/27/covid-booster-shots-could-go-to-at-risk-groups-in-september-uk-vaccines-minister">already underway</a>, but it is too early to say whether they will be needed to control B1617 specifically.</p>
<p>However, a more effective way to prevent variants causing issues around the world would be to prevent them from spreading in the first place. Strict travel restrictions, such as those seen in <a href="https://covid19.govt.nz/travel-and-the-border/travel-to-new-zealand/">New Zealand</a> and <a href="https://www.forbes.com/sites/williamhaseltine/2021/03/24/what-can-we-learn-from-australias-covid-19-response">Australia</a>, may seem a burden, but have allowed relative normality to return in these countries with little fear of variants disrupting efforts to get back to normal. It’s with this hope that the UK has added India to its red list – essentially banning travel from the country.</p><img src="https://counter.theconversation.com/content/159269/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Grace C Roberts works for Queens University, Belfast and receives funding from the Wellcome Trust.</span></em></p>A coronavirus variant with a double mutation has been found in the UK, with cases currently doubling every week.Grace C Roberts, Research Fellow in Virology, Queen's University BelfastLicensed as Creative Commons – attribution, no derivatives.