tag:theconversation.com,2011:/us/topics/vibrio-cholerae-43704/articlesVibrio cholerae – The Conversation2023-09-06T09:47:53Ztag:theconversation.com,2011:article/2125642023-09-06T09:47:53Z2023-09-06T09:47:53ZFrom fatal allergies to heart attacks and malaria – the devastating health effects of global warming in Africa<p>The winds that whip the towns of the Eastern Cape in South Africa have the power to generate energy. But on a dry, hot day, those winds can gather up embers and dump them into tinder dry savannah and forest, destroying crops, fodder and homes, and taking lives. </p>
<p>Wild fires create their own weather systems, generating fire storms with devastating effects. </p>
<p>Global warming will increase the number of days of shimmering heat, creating the ideal conditions for fire. In the past months, southern Europe and North Africa have experienced record-breaking temperatures and fierce fires, and the terrible effects of both on human lives, habitat and environment. The southern hemisphere is next.</p>
<p>But heat, not fire, is the <a href="https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(21)01860-2/fulltext">major cause of death worldwide</a>. The extremes in Europe and the US augur future changes globally. Countries throughout southern Africa, parts of east Africa and Madagascar are all projected to face rapidly <a href="https://www.un.org/africarenewal/magazine/december-2018-march-2019/global-warming-severe-consequences-africa">increasing temperatures</a> to the end of this century. </p>
<p>I am an anthropologist and public health academic, working both in Australia and South Africa. Both countries are recurrently affected by the <a href="https://www.weather.gov/mhx/ensowhat">El Niño–Southern Oscillation</a> and resultant sea rise, with floods, drought and higher temperature in its wake. Global warming and El Niño combined suggest that the years ahead will result in increasing, devastating impacts. </p>
<h2>Heat, air quality and health</h2>
<p>As is clear from reports from multilateral agencies such as the <a href="https://www.ipcc.ch/report/ar6/wg2/">Intergovernmental Panel on Climate Change</a> and national bodies such as the <a href="https://health2016.globalchange.gov/downloads">US Global Change Research Program</a>, high temperatures can be <a href="https://www.who.int/news-room/fact-sheets/detail/the-top-10-causes-of-death">fatal</a>, and vast populations worldwide are vulnerable.</p>
<p>High <a href="https://www.who.int/news-room/fact-sheets/detail/climate-change-heat-and-health">temperatures</a> cause heat stroke, heat exhaustion, heart attacks, strokes and other cardiovascular disease.</p>
<p>South Africa will experience more heat waves, so more heat-related deaths are likely. People in informal settlements, and badly maintained and crowded buildings, are especially vulnerable to heat stress. </p>
<p>Cities are also hot spots. Heat absorbed by roads and buildings results in the urban <a href="https://www.sciencedirect.com/topics/engineering/urban-heat-island-effect">“heat island effect”</a>, while increased use of energy for cooling adds to greenhouse gas emissions. </p>
<h2>Less food, lower nutrition</h2>
<p>On the continent food security is directly threatened by extreme events, but also more broadly by climate change and global warming. In<a href="https://jamba.org.za/index.php/JAMBA/article/view/562"> South Africa</a>, drought recurrently affects subsistence agriculture, livestock and commercial crops. This has already stimulated interest in <a href="https://www.frontiersin.org/articles/10.3389/fsufs.2021.692185/full">local coping strategies</a> faced with food insecurity.</p>
<p>The impact of drought on food and nutrition will be felt by the most vulnerable, including infants, small children and pregnant women and those who already live on or below the poverty line.</p>
<p>Large numbers of people across the continent live as subsistence farmers, and in the absence of food or water we are likely to see increased migration and humanitarian crises. </p>
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Read more:
<a href="https://theconversation.com/climate-change-will-force-up-to-113m-people-to-relocate-within-africa-by-2050-new-report-193633">Climate change will force up to 113m people to relocate within Africa by 2050 - new report</a>
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<p>In South Africa, too, a large proportion of the population relies on <a href="https://www.statssa.gov.za/?p=1447">subsistence farming or other small-scale farming.</a> Crop failure and drought, combined with increased food costs associated with disruptions to global food resources, will affect every one of us. </p>
<h2>Every drop counts</h2>
<p>Drought and water shortages add to these risk factors. Humans require adequate hydration to survive, and the combination of increasing temperatures and water shortages heightens the risk of organ failure and death.</p>
<p>In addition, dependence on poor quality and contaminated water has an impact on household and personal hygiene, and intestinal infections. </p>
<p><em>Vibrio cholerae</em> – the bacteria that cause cholera – is present in waterways in both high and lower income countries, and infection can be mild. But increased concentrations of the bacteria without rapid intervention to prevent severe dehydration can be lethal. The sharp increase in cholera and other <a href="https://www.ncbi.nlm.nih.gov/books/NBK2302/#:%7E:text=Diarrheal%20diseases%20remain%20one%20of,to%20four%20years%20of%20age.">diarrhoeal diseases</a> worldwide is associated with rising temperatures and drought. </p>
<h2>Neglected diseases</h2>
<p>Other viral and bacterial infectious diseases, especially prevalent in Africa, are also likely to increase with global warming. Bundled together as <a href="https://journals.plos.org/plosntds/article?id=10.1371/journal.pntd.0000332">“neglected diseases of poverty”</a>, these include both parasitic and viral vector borne diseases such as Rift Valley fever, malaria, filariasis, schistosomiasis, dengue fever, chikungunya and <a href="https://www.sciencedirect.com/science/article/pii/S266727822100081X?via%3Dihub">influenza</a> as well as arboviruses such as different influenza pathogens. </p>
<p>The ways in which climate change will affect different vector borne disease will vary. Sluggish and stagnant waterways and polluted water sources are one risk factor. </p>
<p>There is growing evidence of <a href="https://www.lowyinstitute.org/the-interpreter/what-climate-change-means-mosquito-borne-diseases">mosquito migration </a>to higher altitudes, infecting people who have not been exposed before. </p>
<p>At the same time, there is growing evidence of vector behavioural change and resistance to insecticides in some settings, including the <a href="https://www.nature.com/articles/s41598-020-71187-4">Ifakara</a> region of Tanzania.</p>
<h2>So where does this leave us?</h2>
<p>When the Intergovernmental Panel on Climate Change was established in 1988, we had a choice to interrupt climate change and slow global warming. </p>
<p>Globalisation, national politics and global capitalism have meant we have failed, and 35 years on we face an inevitable crisis. </p>
<p>This does not mean there is nothing we can do to halt the destruction of planetary life. </p>
<p>It does require that we urgently and radically change how we provide and use energy, how we live, and how we <a href="https://www.weforum.org/agenda/2022/10/3-key-fronts-africa-climate-change/">change living conditions</a> for those who are, by the circumstances of their everyday lives, most at risk of the lethal effects of global warming.</p><img src="https://counter.theconversation.com/content/212564/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Lenore Manderson 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>Africa’s future looks catastrophic if we don’t act now on climate change.Lenore Manderson, Distinguished Professor, Public Health and Medical Anthropology, University of the WitwatersrandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2002262023-04-11T12:04:46Z2023-04-11T12:04:46ZLooming behind antibiotic resistance is another bacterial threat – antibiotic tolerance<figure><img src="https://images.theconversation.com/files/519955/original/file-20230407-28-ddggzn.jpg?ixlib=rb-1.1.0&rect=0%2C3%2C2309%2C1292&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Tolerant bacteria are dormant until an antibiotic threat has passed, then reemerge to conduct business as usual.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/pseudomonas-aeruginosa-bacterium-illustration-royalty-free-image/1201441647">Christoph Burgstedt/Science Photo Library via Getty Images</a></span></figcaption></figure><p>Have you ever had a nasty infection that just won’t seem to go away? Or a runny nose that keeps coming back? You may have been dealing with a bacterium that is tolerant of, though not yet resistant to, antibiotics. </p>
<p>Antibiotic resistance is a huge problem, contributing to <a href="https://doi.org/10.1016/S0140-6736(21)02724-0">nearly 1.27 million deaths worldwide in 2019</a>. But antibiotic tolerance is a covert threat that researchers have only recently begun to explore. </p>
<p><a href="https://doi.org/10.1371/journal.ppat.1008892">Antibiotic tolerance</a> happens when a bacterium manages to survive for a long time after being exposed to an antibiotic. While <a href="https://doi.org/10.1128/microbiolspec.VMBF-0016-2015">antibiotic-resistant</a> bacteria flourish even in the presence of an antibiotic, tolerant bacteria often exist in a dormant state, neither growing nor dying but putting up with the antibiotic until they can “reawaken” once the stress is gone. Tolerance has been <a href="https://www.doi.org/10.1126/science.aaj2191">linked to the spread of antibiotic resistance</a>.</p>
<p>I am a <a href="https://doerr.wicmb.cornell.edu/current-lab-members/">microbiologist</a> who studies antibiotic tolerance, and I seek to uncover what triggers tolerant bacteria to enter a protective dormant slumber. By understanding why bacteria have the ability to become tolerant, researchers hope to develop ways to avoid the spread of this ability. The exact mechanism that sets tolerance apart from resistance has been unclear. But one possible answer may reside in a process that has been overlooked for decades: how bacteria <a href="https://doi.org/10.3389/fmicb.2020.577564">create their energy</a>.</p>
<h2>Cholera and antibiotic tolerance</h2>
<p>Many antibiotics are designed to <a href="https://doi.org/10.1039/C6MD00585C">break through the bacteria’s outer defenses</a> like a cannonball through a stone fortress. Resistant bacteria are immune to the cannonball because they can either destroy it before it damages their outer wall or change their own walls to be able to withstand the impact. </p>
<p>Tolerant bacteria can remove their wall entirely and avoid damage altogether. No wall, no target for the cannonball to smash. If the threat goes away before too long, the bacterium can rebuild its wall to protect it from other environmental dangers and resume normal functions. However, it is still unknown how bacteria know the antibiotic threat is gone, and what exactly triggers their reawakening. </p>
<p>My colleagues and I at the <a href="https://doerr.wicmb.cornell.edu/">Dörr Lab at Cornell University</a> are trying to understand processes of activation and reawakening in the tolerant bacteria responsible for cholera, <em>Vibrio cholerae</em>. <em>Vibrio</em> is <a href="https://doi.org/10.3389/fitd.2021.691604">rapidly evolving resistance</a> against various types of antibiotics, and doctors are concerned. As of 2010, <em>Vibrio</em> is already <a href="https://doi.org/10.1016/j.vaccine.2019.06.031">resistant to 36 different antibiotics</a>, and this number is expected to continue rising.</p>
<p>To study how <em>Vibrio</em> develops resistance, we chose a strain that is tolerant to a class of antibiotics <a href="https://doi.org/10.3389/fpubh.2016.00231">called beta-lactams</a>. Beta-lactams are the cannonball sent to destroy the bacteria’s fortress, and <em>Vibrio</em> adapts by activating two genes that temporarily remove its cell wall. I witnessed this phenomenon using a microscope. After removing its cell wall, the bacteria activate even more genes that morph it into fragile globs that can survive the effects of the antibiotic. Once the antibiotic is removed or degraded, <em>Vibrio</em> returns to its normal rod shape and continues to grow. </p>
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<figcaption><span class="caption">Normally rod-shaped <em>Vibrio cholerae</em> remove their cell walls and turn into globs in the presence of penicillin, enabling them to survive longer.</span></figcaption>
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<figcaption><span class="caption"><em>Vibrio cholerae</em> revert back to their rod-shaped structure once the antibiotic threat is removed.</span></figcaption>
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<p>In people, this process of tolerance is seen when a doctor prescribes an antibiotic, typically doxycycline, to a patient infected with cholera. The antibiotic temporarily seems to stop the infection. But then the symptoms start back up again because the antibiotics never fully cleared the bacteria in the first place.</p>
<p>The ability to revert back to normal and grow after the antibiotic is gone is the key to tolerant survival. Exposing <em>Vibrio</em> to an antibiotic for a long enough time would eventually kill it. But a standard course of antibiotics often isn’t long enough to get rid of all the bacteria even in their fragile state.</p>
<p>However, taking a medicine for a prolonged period can harm healthy bacteria and cells, causing further discomfort and illness. Additionally, <a href="https://doi.org/10.3389/fcimb.2020.572912">misuse and extended exposure</a> to antibiotics can increase the chances of other bacteria residing in the body becoming resistant.</p>
<h2>Other bacteria developing tolerance</h2>
<p><em>Vibrio</em> isn’t the only species to exhibit tolerance. In fact, researchers have recently identified many infectious bacteria that have developed tolerance. A bacteria family called <a href="https://doi.org/10.1371/journal.pbio.1001928">Enterobacteriaceae</a>, which include major food-borne disease pathogens <a href="https://doi.org/10.1371/journal.pbio.1001928"><em>Salmonella</em></a>, <a href="https://doi.org/10.1128/AAC.01282-08"><em>Shigella</em></a> and <a href="https://doi.org/10.1038/s41598-021-85509-7"><em>E. coli</em></a>, are just a few of the many types of bacteria that are capable of antibiotic tolerance.</p>
<p>As every bacterium is unique, the way one develops tolerance seems to be as well. Some bacteria, like <em>Vibrio</em>, <a href="https://doi.org/10.1128/AAC.00756-19">erase their cell walls</a>. Others can <a href="https://doi.org/10.1038/nchembio.1754">alter their energy sources, increase their ability to move or simply pump out</a> the antibiotic.</p>
<p>I recently found that a <a href="https://doi.org/10.1128/jb.00476-22">bacterium’s metabolism</a>, or the way it breaks down “food” to make energy, may play a significant role in its ability to become tolerant. Different structures within a bacterium, including its outer wall, are made of specific building blocks like proteins. Stopping the bacterium’s ability to craft these pieces weakens its wall, making it more likely to take damage from the outside environment before it can take the wall down.</p>
<h2>Tolerance and resistance are connected</h2>
<p>Although there has been considerable research on how bacteria develop tolerance, a key piece of the puzzle that has been neglected is how tolerance leads to resistance.</p>
<p>In 2016, researchers discovered how to <a href="https://doi.org/10.1038/nmicrobiol.2016.20">make bacteria tolerant in the laboratory</a>. After repeated exposure to different antibiotics, <em>E. coli</em> cells were able to adapt and survive. DNA, the genetic material containing instructions for cell function, is a fragile molecule. When DNA is damaged rapidly by stress, such as antibiotic exposure, the cell’s repair mechanisms tend to mess up and cause mutations that can create resistance and tolerance. Because <em>E. coli</em> is similar to many different types of bacteria, these researchers’ findings revealed that, ironically, essentially any bacteria can develop tolerance if pushed to their limits by the antibiotics meant to kill them. </p>
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<figcaption><span class="caption">Bacteria form large communities in biofilms.</span></figcaption>
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<p>Another recent key discovery was that the longer bacteria remain tolerant, the more likely they are to <a href="https://doi.org/10.1073/pnas.2209043119">develop mutations leading to resistance</a>. Tolerance allows bacteria to develop a resistance mutation that reduces their chances of being killed during antibiotic treatment. This is especially relevant to bacterial communities often seen in <a href="https://doi.org/10.2147/IDR.S379502">biofilms that tend to coat high-touch surfaces in hospitals</a>. Biofilms are slimy layers of bacteria that ooze a protective jelly that makes antibiotic treatment difficult and DNA sharing between microbes easy. They can induce bacteria to evolve resistance. These conditions are thought to mimic what could be happening during antibiotic-treated infections, in which many bacteria are living next to one another and sharing DNA. </p>
<p>Researchers are calling for more research into antibiotic tolerance with the hope that it will lead to <a href="https://doi.org/10.1128/mBio.02095-19">more robust treatments</a> in both infectious diseases and cancers. And there is reason to be hopeful. In one promising development, a mouse study found that <a href="https://doi.org/10.1126/science.1211037">decreasing tolerance also reduced resistance</a>. </p>
<p>Meanwhile, there are steps everyone can take to aid in the battle against antibiotic tolerance and resistance. You can do this by <a href="https://www.who.int/news-room/fact-sheets/detail/antibiotic-resistance">taking an antibiotic exactly as prescribed</a> by a doctor and finishing the entire bottle. Brief, inconsistent exposure to a medicine primes bacteria to become tolerant and eventually resistant. Smarter use of antibiotics by everyone can stop the evolution of tolerant bacteria.</p><img src="https://counter.theconversation.com/content/200226/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Megan Keller receives funding from the National Science Foundation Graduate Research Fellowship Program and the National Institutes of Health (NSF GRFP #DGE-1650441 and NIH R01-AI143704)</span></em></p>Antibiotic resistance has contributed to millions of deaths worldwide. Research suggests that any bacteria can develop antibiotic tolerance, and possibly resistance, when pushed to their limits.Megan Keller, Ph.D. Candidate in Microbiology, Cornell UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1977992023-01-14T09:53:17Z2023-01-14T09:53:17ZWhy cholera continues to threaten many African countries<figure><img src="https://images.theconversation.com/files/504431/original/file-20230113-17-bb62ey.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Key to preventing cholera is a good supply of water.</span> <span class="attribution"><span class="source">Getty images</span></span></figcaption></figure><p><em>Many African countries are periodically affected by outbreaks of cholera. For instance, Malawi’s current outbreak, the <a href="https://www.bloomberg.com/news/articles/2023-01-12/worst-cholera-outbreak-in-decades-kills-750-people-in-malawi">worst</a> in two decades, has claimed <a href="https://www.theeastafrican.co.ke/tea/rest-of-africa/cholera-outbreak-kills-620-in-malawi-4073880#:%7E:text=Malawi%20has%20recorded%2018%2C222%20cholera,Health%20Minister%20Khumbize%20Chiponda%20announced">hundreds</a> of lives and forced the closure of schools and many businesses. Cholera deaths have now been <a href="https://www.bloomberg.com/news/articles/2023-05-22/south-african-capital-hit-by-cholera-outbreak-with-10-dead">reported</a> in South Africa too.</em></p>
<p><em>Microbiologist Sam Kariuki, the director of Kenya’s Medical Research Institute, explains what cholera is and why it’s so hard to control in Africa.</em></p>
<h2>Why is cholera still such a big issue for African countries?</h2>
<p>Cholera is a disease <a href="https://www.gtfcc.org/research/cholera-prevention-preparedness-and-control-in-kenya-through-hotspot-mapping-genotyping-exposure-assessment-and-wash-oral-cholera-vaccine-interventions/">caused and spread by</a> bacteria – specifically <em>Vibrio cholerae</em> – which you can get by eating or drinking contaminated food or water. </p>
<p>It’s an <a href="https://books.google.co.ke/books?id=qpjshPr7HVcC&pg=PA197&lpg=PA197&dq=cholera+and+bangal&source=bl&ots=4htxUE4c61&sig=S52TKJb0YKHttBcyNZt2jJRtLcY&hl=en&sa=X&redir_esc=y#v=onepage&q=cholera%20and%20bangal&f=false">old disease</a> which has mostly <a href="https://www.ncbi.nlm.nih.gov/pubmed/2857326">affected</a> developing countries, many of which are in Africa. Between 2014 and 2021 Africa <a href="https://reliefweb.int/report/world/who-and-partners-revamp-war-against-cholera-africa">accounted for</a> 21% of cholera cases and 80% of deaths reported globally.</p>
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<p>In several African countries, cholera is the leading cause of severe diarrhoea. In 2021, the World Health Organization <a href="https://reliefweb.int/report/world/who-and-partners-revamp-war-against-cholera-africa">reported</a> that Africa experienced its highest ever reported numbers – more than 137,000 cases and 4,062 deaths in 19 countries.</p>
<p>It has persisted in Africa partly because of <a href="https://www.washingtonpost.com/politics/2022/01/28/is-africa-losing-ground-battle-water-sanitation/">worsening</a> sanitation, poor and unreliable water supplies and worsening socioeconomic conditions. For instance, when people’s incomes can’t keep up with inflation they’ll move to more affordable housing – often this is in congested, unsanitary settings where water and other hygiene services are already stretched to the limit.</p>
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<a href="https://theconversation.com/kenyas-urban-poor-are-being-exploited-by-informal-water-markets-144582">Kenya's urban poor are being exploited by informal water markets</a>
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<p>In addition, in the last decade, many African countries have witnessed an <a href="https://www.afdb.org/en/documents/africas-urbanisation-dynamics-2022-economic-power-africas-cities">upsurge in population migration</a> to urban areas in search of livelihoods. Many of these people end up in poor urban slums where water and sanitation infrastructure remains a challenge. </p>
<p>Displaced populations – a major concern in several African countries – are also very vulnerable to water and food contamination. </p>
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<span class="caption">Sadiki Sabimana, an internally displaced person, holds water he believes is contaminated with cholera, in the DRC’s Masisi area.</span>
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<p>It’s important to control cholera because it can cause severe illness and death. In mild cases cholera can be managed through oral rehydration salts to replace lost fluids and electrolytes. Severe cases may require antibiotic treatment. It’s vital to diagnose and treat cases quickly – cholera can <a href="http://www.who.int/mediacentre/factsheets/fs107/en/">kill within hours</a> if untreated. </p>
<p>In 2015, it was <a href="https://bmjopen.bmj.com/content/11/3/e044615">estimated that</a> over one million cases in 44 African countries resulted in an economic burden of US$130 million from cholera-related illness and its treatment. </p>
<h2>What’s missing in the response?</h2>
<p>African governments must acknowledge that the burden of cholera is huge. In my opinion, governments in endemic areas don’t recognise cholera as a major issue until there’s a big outbreak, when it’s out of control. They treat it as a once off. </p>
<p>The burden of cholera could get worse unless governments put measures in place to control and prevent outbreaks. They need to address water and hygiene infrastructure. </p>
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<a href="https://theconversation.com/cholera-how-african-countries-are-failing-to-do-even-the-basics-74445">Cholera: how African countries are failing to do even the basics</a>
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<p>There must also be community engagement. For instance, widespread messaging that encourages hand washing, boiling water and other preventive measures. Community health <a href="https://www.cdc.gov/mmwr/volumes/65/wr/mm6503a7.htm">extension workers</a> are key in getting these messages across and distributing supplies during an outbreak.</p>
<p>For the most vulnerable populations we must apply oral cholera vaccines. Data on cholera hotspots from surveillance studies will be vital to ensure critical populations are targeted first. </p>
<p>There are various brands and variation of the oral cholera vaccine, and they are all easy to administer because they are taken orally. They have an effectiveness rate of <a href="https://www.cdc.gov/cholera/vaccines.html#:%7E:text=The%20vaccine%20manufacturer%20reports%20Vaxchora,3%E2%80%936%20months%20after%20vaccination.">between</a> 60% to 80% but require a yearly booster. There’s not been a concerted vaccination campaign in many countries, however, because governments are not taking the prevention and control of the disease seriously. </p>
<p>Finally, the issue of drug resistance needs to be addressed. Drug resistance has made it possible for these cholera strains to stay longer in the environment. </p>
<p>I was part of a team that conducted a <a href="http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0074829">study</a> in Kenya which found that bacteria that causes cholera has become resistant to some antibiotics. Some types of drug resistance are caused by a natural interaction of the <em>Vibrio cholerae</em> bacteria with other drug resistant bacteria in the environment. </p>
<p>The overuse of antibiotics also contributes to drug resistance. Government agencies should develop ways to monitor the use of antibiotics and restrict their prescription. Regulation of antibiotic use in animals should also be improved. Healthcare workers also need to be trained in the proper use of antibiotics.</p>
<h2>Have there been any recent advances?</h2>
<p>One important one has been the development of rapid diagnostic tests that can be used by health workers in the field. These kits are available at costs far lower than lab culture costs. Using them makes it possible to confirm outbreaks promptly so treatment can be initiated. </p>
<p>In addition, more countries are now adopting the oral cholera vaccine for prevention and control. </p>
<p>What is lacking is a concerted effort for all endemic countries – which I consider to be all countries in sub-Saharan Africa – to have joint measures to tackle cross-border transmission and persistence of cholera outbreaks. </p>
<p>Some countries are still in denial about outbreaks. This is partly due to fears about repercussions on trade and tourism. But in an interconnected world this attitude isn’t helpful. </p>
<p>I am optimistic that we can control cholera in African settings. In the short term this could be done through raising awareness among vulnerable populations and interventions like the oral cholera vaccine.</p>
<p>In the long term African countries need improved water hygiene infrastructure, housing and enhanced socioeconomic conditions. But there must be a strong will by relevant government ministries to work together to realise these goals.</p><img src="https://counter.theconversation.com/content/197799/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Samuel Kariuki 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>Cholera has persisted longer in Africa largely due to worsening hygiene and sanitation situations in urban areas.Samuel Kariuki, Chief Research Scientist and Director, Centre for Microbiology Research, Kenya Medical Research InstituteLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1630182021-07-11T09:49:10Z2021-07-11T09:49:10ZCholera is still a danger in Nigeria: here’s what the government can do<figure><img src="https://images.theconversation.com/files/409905/original/file-20210706-21-tgkvgo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Cholera outbreaks are more common in internally displaced persons camps </span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/people-stand-in-an-alleyway-in-one-of-the-idp-camps-in-news-photo/1021005932?adppopup=true">Stefan Heunis/AFP via Getty Images </a></span></figcaption></figure><p><a href="https://ncdc.gov.ng/news/331/ncdc-supports-states-to-intensify-cholera-outbreak-response">Thousands of cases</a> of cholera have been reported in Nigeria between January and June 2021. The northern states of Bauchi, Gombe, Kano, Plateau and Zamfara are among those <a href="https://www.garda.com/crisis24/news-alerts/492061/nigeria-cholera-outbreak-continues-in-north-central-states-during-june-primarily-bauchi-state-maintain-strict-food-and-water-precautions#:%7E:text=Nigerian%20authorities%20report%20ongoing%2C%20elevated,available%20as%20of%20June%2018">affected</a>. </p>
<p>Cholera is an acute diarrhoeal disease <a href="https://bmcpublichealth.biomedcentral.com/articles/10.1186/s12889-018-6299-3">caused</a> by <em>Vibrio cholerae</em> bacteria. It is passed on from faeces through contaminated food, drinks and unhygienic environments, and causes severe dehydration. Infected people can die if their illness is not quickly managed with <a href="https://pubmed.ncbi.nlm.nih.gov/22461716/">oral rehydration</a>.</p>
<p>In the past, cholera infections were common in many countries around the globe. Now they are mostly confined to <a href="https://bmcpublichealth.biomedcentral.com/articles/10.1186/s12889-019-7559-6">developing regions</a> because the disease is associated with poor nutrition, poor water quality and poor sanitation.</p>
<p>The proportion of people who die from reported cholera remains higher in <a href="https://www.cdc.gov/cholera/africa/index.html">Africa</a> than elsewhere. In Nigeria, <a href="https://bmcpublichealth.biomedcentral.com/articles/10.1186/s12889-019-7559-6">huge outbreaks</a> were recorded in 1991, 2010, 2014 and 2018. <a href="https://bmcpublichealth.biomedcentral.com/articles/10.1186/s12889-019-7559-6">In 2018</a>, there were 43,996 cholera cases and 836 deaths: a case fatality rate of 1.90%.</p>
<h2>Drivers of cholera</h2>
<p>Susceptibility to cholera is <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3428179/">associated</a> with demographic and socioeconomic factors, including age and nutritional status. <a href="https://bmcpublichealth.biomedcentral.com/articles/10.1186/s12889-020-08521-y">Malnutrition</a> drives transmission and severity. Vitamin B12 deficiency and gastritis are <a href="https://bmcpublichealth.biomedcentral.com/articles/10.1186/1471-2458-14-1167">risk factors</a> for infection. </p>
<p>The bacteria that cause cholera are expelled through the faeces for nearly two weeks after infection. They can be shed into the environment to infect other people.</p>
<p>Lack of access to safe drinking water and poor personal and environmental hygiene are basic factors that <a href="https://pubmed.ncbi.nlm.nih.gov/30123408/">promote</a> the spread of cholera. Infection also occurs when people <a href="http://article.sapub.org/10.5923.j.phr.20140401.02.html">eat or drink</a> something that’s already contaminated by the bacteria. <a href="https://pubmed.ncbi.nlm.nih.gov/12364378/">Evidence</a> from the 1995-1996 outbreak in Kano state revealed that poor hand hygiene before meals and vended water played a role. </p>
<p>Population congestion is also a <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6592437/">factor</a> in the spread of cholera. This can happen through migration to commercial hubs such as Kano. It can also happen when humanitarian disasters force displaced people to live in <a href="https://bmcpublichealth.biomedcentral.com/articles/10.1186/s12889-018-6299-3">camps</a>. There, they often have inadequate water supply and may be unable to observe good sanitary practices. Over <a href="https://www.unhcr.org/nigeria-emergency.html#:%7E:text=Over%203.2%20million%20people%20are,refugees%20in%20the%20four%20countries.">2.9 million people</a> are currently living as internally displaced persons in north-eastern Nigeria. At least, 10,000 cholera cases and 175 related deaths <a href="https://www.garda.com/crisis24/news-alerts/175011/nigeria-cholera-outbreak-in-yobe-adamawa-and-borno-states-update-4">were reported</a> in Yobe, Adamawa and Borno states predominantly in crowded camps in 2018.</p>
<p>Living in urban and peri-urban <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7656999/">slums</a> promotes cholera too. This is because regular water supply and toilet facilities are not adequately available. Only <a href="https://www.unicef.org/nigeria/water-sanitation-and-hygiene#:%7E:text=Only%2026.5%20per%20cent%20of,water%20sources%20and%20sanitation%20facilities.">26.5%</a> of the Nigeria population use improved drinking water sources and sanitation facilities, and <a href="https://www.unicef.org/nigeria/water-sanitation-and-hygiene#:%7E:text=Only%2026.5%20per%20cent%20of,water%20sources%20and%20sanitation%20facilities.">23.5%</a> defecate in the open.</p>
<h2>Cholera control in Nigeria</h2>
<p>The Nigerian government has made some efforts to control the disease. It is implementing programmes to improve water supply, basic sanitation and good hygiene practices, but these are usually implemented after outbreaks.
Led by the Federal Ministry of Water Resources, the government has <a href="https://www.gtfcc.org/wp-content/uploads/2020/08/6th-gtfcc-working-group-on-ocv-meeting-2019-james-onah.pdf">provided</a> 510,663 litres of water daily in 39 locations in Adamawa state, which accounted for 50% of cholera cases in 2019. </p>
<p>It has also <a href="https://www.gtfcc.org/wp-content/uploads/2020/08/6th-gtfcc-working-group-on-ocv-meeting-2019-james-onah.pdf">provided</a> mobile solar-powered boreholes. The International Organisation for Migration <a href="https://storyteller.iom.int/stories/sunny-day-gubio-camp-how-clean-energy-bringing-relief-conflict-affected-nigeria">maintains</a> 58 solar-powered boreholes in Borno state and drilled 11 new ones in 2019. It also rehabilitated 10 and connected them to solar power. </p>
<p>In response to an outbreak at the displaced persons’ camps in Borno state in 2017, the National Primary Healthcare Development Agency and other partners conducted oral cholera vaccination <a href="https://gh.bmj.com/content/5/6/e002431">campaigns</a>. </p>
<p>The oral cholera vaccine is not a part of the routine vaccination in Nigeria. It is <a href="https://www.cdc.gov/vaccines/hcp/vis/vis-statements/cholera.html">not 100% effective against cholera</a> and does not protect against other foodborne or waterborne diseases. It is not a longtime solution to cholera and only bridges the gap between emergency response and longtime cholera control. In 2017, reactive <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7326259/">oral cholera vaccine campaigns</a> were implemented in Borno to stop an outbreak. Investments in water, sanitation and hygiene infrastructure are always necessary. </p>
<p>Health education campaigns are conducted by outbreak investigation teams from the Nigeria Centre for Disease Control following <a href="https://bmcpublichealth.biomedcentral.com/articles/10.1186/s12889-019-7559-6">confirmation</a> of cholera outbreaks. UNICEF has promoted <a href="https://www.unicef.org/nigeria/media/1286/file/Cholerla-outbreak-NE-Nigeria-UNICEF-response-2017.pdf.pdf">chlorination of water</a> among communities in cholera hotspots. This has benefited an estimated 4.5 million people in Borno, Adamawa and Yobe states, including 680,000 displaced people in urban centres. </p>
<h2>What is yet to be done</h2>
<p>Much remains to be done since cholera has not been conquered completely. </p>
<p>Cholera has been described as a “disease of poverty” because social risk factors play significant roles in its transmission. </p>
<p>In line with best practices of multisectoral control, we recommend the following:</p>
<p>National governments in cholera-affected countries should take the lead with support from <a href="https://www.gtfcc.org/about-cholera/">Global Task Force on Cholera Control</a> partners. Multi-sectoral interventions to effectively control cholera are based on a package of measures that should be well coordinated. They include creating access to safe drinking water and sanitation; improving surveillance, reporting and readiness; and community engagement <a href="https://www.gtfcc.org/about-cholera/">to raise awareness and promote good hygiene practices</a>.</p>
<p>Regular health education during and after outbreaks is necessary. Community engagement would help to identify people who would be responsible for timely reporting of suspected cases of cholera. The teams that manages outbreaks at the local, state and federal government levels should be well coordinated and respond swiftly when notified of a cholera outbreak. </p>
<p>These steps have been seen to work in <a href="https://www.unicef.org/stories/mobilizing-communities-cholera-outbreak-south-sudan">South Sudan</a> and <a href="https://www.afro.who.int/news/engaging-communities-tackle-cholera-tanzania">Tanzania</a> but require political will to get different sectors to collaborate.</p><img src="https://counter.theconversation.com/content/163018/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Olayinka Stephen Ilesanmi 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>Nigeria needs a multisectoral approach to break its annual cholera epidemic.Olayinka Stephen Ilesanmi, Lecturer, Department of Community Medicine, University of IbadanLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1505512020-11-24T15:02:14Z2020-11-24T15:02:14ZRiver of bacteria: a South African study pinpoints what’s polluting the water<figure><img src="https://images.theconversation.com/files/371020/original/file-20201124-23-9049u7.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Apies river downstream of the informal settlement and the village of Hammanskraal.</span> <span class="attribution"><span class="source">Author supplied</span></span></figcaption></figure><p>In 2010, the United Nations recognised access to clean water and sanitation as a fundamental human right. However, over <a href="https://www.worldtoiletday.info/">4.1 billion</a> people around the world, particularly in low- and middle-income countries, still do not have access to this human right.</p>
<p>Clean and safe water is necessary for basic life functions — for drinking, for cooking, for bathing, and more. When it is not available, people resort to alternative sources, which are often polluted with pathogenic bacteria arising from human waste. Using such water exposes people to waterborne diseases such as diarrhoea.</p>
<p>In cities, most households have access to treated water and good sanitation services. However, over <a href="https://www.unicef.org/esa/sanitation-and-hygiene">340 million</a> people in sub-Saharan Africa, mostly in rural communities and informal settlements, do not. They may rely on rivers, lakes, and streams for their. In addition, over <a href="https://www.unicef.org/esa/sanitation-and-hygiene">270 million</a> practise open defecation or have poorly constructed toilets. Most have no choice but to defecate outdoors, often disposing of their faeces directly into rivers — the same ones they use as sources of water.</p>
<p>We, a group of researchers in South Africa, wanted to know more about how different human activities around rivers in the country affected the microbial quality of the water. We wanted to understand the extent to which <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5664689/">informal settlements</a>, where access to basic sanitation and hygiene is limited or absent, affected the presence of waterborne bacteria.</p>
<p>We set out to explore how different human activities, such as sewage treatment plants, informal settlements and agriculture, affected the microbial quality of river water. We also used a mathematical model to show whether people could get sick from drinking untreated water from the river. We looked at <em>E. coli</em> as the indicator organism and <em>Vibrio</em>, <em>Salmonella</em> and <em>Shigella</em> as pathogenic organisms. Indicator organisms indicate the possible presence of pathogens, which are microorganisms that can cause disease. </p>
<p>Our <a href="https://pubmed.ncbi.nlm.nih.gov/26318680/#:%7E:text=Seasonal%20variations%20had%20an%20impact,coli%20concentrations">research</a> found that in <a href="https://pubmed.ncbi.nlm.nih.gov/26318680/#:%7E:text=Seasonal%20variations%20had%20an%20impact,coli%20concentrations.">informal settlements</a> where sanitation and waste management facilities were absent, a high number of bacteria were often present in the water of the river we studied. Some of these bacteria were pathogenic forms of <em>E. coli</em>, which, when consumed, could make people sick. We also observed that the people living there frequently used the river water, without any treatment, for personal hygiene such as bathing and brushing their teeth. The river was also often used for rituals, which involved immersing oneself several times into the water as a form of spiritual cleansing.</p>
<h2>Samples from before and after activities</h2>
<p>The <a href="https://www.sahistory.org.za/place/apiesrivier-river-which-flows-through-pretoria">Apies river</a> takes its source from the south of the city of Pretoria (one of South Africa’s three capital cities) and flows towards the north of the city, before joining the Pienaars River. Samples were collected at ten different sites along the river. These sites were situated upstream and downstream from the different human activities we looked at. We tested the water in the laboratory for the presence of microorganisms.</p>
<p>There are numerous sewage treatment facilities that <a href="https://rekordeast.co.za/315344/north-residents-protest-sewage-spill-into-apies-river/">discharge wastewater directly into the river</a>. At times the discharged water is <a href="https://ewn.co.za/2011/10/12/Untreated-sewage-flows-into-Apies-River_">not treated</a> due to system failure, or poorly treated when overloaded. The river also receives waste from informal settlements situated along the riverbanks, either directly through dumping or indirectly from surface runoff during heavy rainfall. These <a href="http://www.statssa.gov.za/census/census_2001/urban_rural/urbanrural.pdf">informal settlements</a> are unplanned and the houses are sometimes built on illegally owned land, usually not built according to regulations. So they do not have waste management services.</p>
<p>This river is also used for irrigation. Villagers in <a href="http://www.statssa.gov.za/census/census_2001/urban_rural/urbanrural.pdf">the rural communities</a> – areas that are subdivided into “tribal” areas and commercial farms and usually have few houses – use the river water for their cattle too. The informal and rural settlements use the river directly to dump their waste – including faeces – and for personal and household hygiene.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/371022/original/file-20201124-13-1rbwiyu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Cattle and water" src="https://images.theconversation.com/files/371022/original/file-20201124-13-1rbwiyu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/371022/original/file-20201124-13-1rbwiyu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/371022/original/file-20201124-13-1rbwiyu.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/371022/original/file-20201124-13-1rbwiyu.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/371022/original/file-20201124-13-1rbwiyu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/371022/original/file-20201124-13-1rbwiyu.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/371022/original/file-20201124-13-1rbwiyu.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Cows using the water from the rural community of Potwane in the North.</span>
<span class="attribution"><span class="source">Author supplied</span></span>
</figcaption>
</figure>
<p>We isolated all the tested organisms in the water and sediment samples collected from this river. We found that the number of bacteria isolated before the water passed through informal settlements was lower compared to the number when the river had passed through the settlement. This was because of the lack of toilets in the settlement, forcing the communities to use the river as a toilet. We also found higher numbers of bacteria when the river received wastewater from the sewage treatment facilities. This shows that the treatment plant was discharging poorly treated water containing faeces in the river.</p>
<h2>Getting sick is almost guaranteed</h2>
<p>The World Health Organisation (WHO) recommends that there should be <a href="https://www.who.int/water_sanitation_health/dwq/2edvol3a.pdf">zero</a> <em>E. coli</em> in water meant for drinking. But we found up to 1 million <em>E. coli</em> cells in 100ml of water collected downstream for the informal settlement and sewage treatment facility sites. According to the mathematical model, someone who ingested as little as 1ml of untreated water had almost a 100% chance of getting sick during the rainy season – leading to school absences and missed days of work. </p>
<p>People living in informal settlements and rural areas need to be made aware of the negative impact of open defecation, especially directly into rivers. Where there is no alternative water source, they should be advised to treat the water, for example by boiling it before use.</p>
<p>Governments need to ensure that people living in rural communities and informal settlements have access to toilets and clean water. This can be done by building community toilets or providing them with <a href="https://www.cambridge.org/core/journals/disaster-medicine-and-public-health-preparedness/article/waterless-portable-private-toilet-an-innovative-sanitation-solution-in-disaster-zones/365904320A86CB239EDB3DEDA44D89C6">mobile toilets</a>, where construction may not be possible. Governments also need to ensure that sewage treatment facilities, where available, are functioning correctly to avoid the discharge of poorly treated water containing harmful bacteria and faeces into rivers.</p>
<p>The Department of Water and Sanitation of South Africa must also ensure that wastewater treatment plants adhere strictly to Section 39 of the National Water Act, 1998, <a href="https://www.wqms.co.za/infopages/236">which provides guidance</a> for quality and management of wastewater.</p><img src="https://counter.theconversation.com/content/150551/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Akebe Luther King Abia is affiliated to the Aspen Institute through the Aspen New Voices Fellowship. He is also a member of the Antimicrobial Research Unit, University of KwaZulu-Natal. This work was funded by the Water Research Commission of South Africa, and was part of a larger project on the dynamics and health implications of microbial pathogens in South African water resource sediments under changing climates</span></em></p>Water at informal settlements, where sanitation and waste management facilities were absent, had high bacteria levels.Akebe Luther King Abia, Research Scientist, University of KwaZulu-NatalLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1170582019-05-17T10:45:43Z2019-05-17T10:45:43ZPhage therapy to prevent cholera infections – and possibly those caused by other deadly bacteria<figure><img src="https://images.theconversation.com/files/274702/original/file-20190515-60549-1s01gkj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Viruses attack and infect a bacterium.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-illustration/3d-illustration-bacteriophage-infecting-bacterium-1126283546?src=S_9nerH_NRM2G4uylbOlTA-1-1">Design_Cells/Shutterstock.com</a></span></figcaption></figure><p>In the latest of a string of high-profile cases in the U.S., a cocktail of bacteria-killing viruses <a href="https://doi.org/10.1038/s41587-019-0133-z">successfully treated a cystic fibrosis patient</a> suffering from a deadly infection caused by a pathogen that was resistant to multiple forms of antibiotics. </p>
<p>Curing infections is great, of course. But what about using these bacteria-killing viruses – bacteriophages – to prevent infections in the first place? Could this work for some diseases? Although using viruses to prevent infections caused by bacterial infections might seem counterintuitive, in the case of bacteriophages: “The enemy of my enemy is my friend.” </p>
<p><a href="https://doi.org/10.1007/978-3-319-07758-1_4">Discovered a little more than 100 years ago</a>, bacteriophages, or phages, are generating renewed interest as potential weapons to fight bacteria that are resistant to multiple antibiotics – the so-called superbugs. Although the recent phage therapy has been focused on the treatment of sick patients, preventing infection stops a disease before it begins, keeping people healthy and preventing the spread of the germ to others.</p>
<p><a href="http://doi.org/10.2436/20.1501.01.292">We are </a><a href="https://www.nature.com/articles/ncomms14187">microbiologists</a> <a href="http://doi.org/10.1128/IAI.01139-08">who study</a> cholera because this ancient disease continues to thrive and can have a devastating impact on communities and <a href="https://en.wikipedia.org/wiki/2010s_Haiti_cholera_outbreak">entire countries</a>. The <a href="https://sackler.tufts.edu/facultyResearch/faculty/camilli-andrew/research">Camilli lab</a> has been focused on the disease for over two decades. We are interested in developing vaccines and phage products to prevent cholera from sickening people and triggering outbreaks. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/274703/original/file-20190515-60563-1ge9tfh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/274703/original/file-20190515-60563-1ge9tfh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=402&fit=crop&dpr=1 600w, https://images.theconversation.com/files/274703/original/file-20190515-60563-1ge9tfh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=402&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/274703/original/file-20190515-60563-1ge9tfh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=402&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/274703/original/file-20190515-60563-1ge9tfh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=505&fit=crop&dpr=1 754w, https://images.theconversation.com/files/274703/original/file-20190515-60563-1ge9tfh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=505&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/274703/original/file-20190515-60563-1ge9tfh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=505&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">This cholera patient is drinking oral rehydration solution in order to counteract his cholera-induced dehydration.</span>
<span class="attribution"><a class="source" href="https://upload.wikimedia.org/wikipedia/commons/a/ad/Cholera_rehydration_nurses.jpg">Centers for Disease Control and Prevention's Public Health Image Library</a></span>
</figcaption>
</figure>
<h2>Cholera outbreaks occur worldwide</h2>
<p>In the case of <a href="https://www.cdc.gov/cholera/index.html">cholera</a>, which is caused by the bacterium <em>Vibrio cholerae</em>, prevention is preferred because it spreads like wildfire once it strikes a community. When this bacterial pathogen is ingested, it inhabits the small intestine, where it releases a potent toxin that triggers vomiting and watery diarrhea, which cause severe dehydration. The vomiting and diarrhea encourage the spread of the pathogen within households and contaminate local water sources. Left untreated, cholera kills 40% of its victims, sometimes within hours of the onset of symptoms. Fortunately, death can be largely prevented by prompt rehydration of cholera victims. </p>
<p>In regions of the world lacking clean water and proper sanitation, <a href="https://www.cdc.gov/healthywater/global/wash_statistics.html">2.5 billion people are at risk</a>, and the CDC estimates that there are <a href="https://www.who.int/news-room/fact-sheets/detail/cholera">up to 4 million cholera cases per year</a>. New epidemics such as the recent massive epidemic in Yemen which has so far <a href="https://www.reuters.com/article/us-yemen-security-cholera/yemen-cholera-outbreak-accelerates-to-10000-cases-per-week-who-idUSKCN1MC23J">sickened over 1.2 million people</a> and the <a href="https://www.africanews.com/2019/05/07/mozambique-fights-cholera-outbreak-after-facing-cyclones//">outbreak in Mozambique</a> are often the consequence of humanitarian crises. War and natural disasters often cause shortages of clean water and impact the poorest and most vulnerable communities. </p>
<p>Cholera is highly transmissible in the community and within households. During outbreaks, an <a href="https://www.sciencedaily.com/releases/2018/06/180625122454.htm">estimated 80% of cases</a> are believed to result from rapid transmission within households, presumably occurring through contamination of household food, water or surfaces with diarrhea or vomit from the initial cholera victim. </p>
<p>Family members typically experience cholera symptoms themselves two to three days after the initial household member became sick. Thus, the people in the most danger are usually siblings and loved ones taking care of the sick person. There is currently no approved medical intervention to immediately protect household members from contracting cholera when it strikes a household. Vaccines for cholera require at least 10 days to take effect, and thus miss the mark in this emergency situation. </p>
<h2>Prevention of cholera using phages</h2>
<p>To address this need, we developed a cocktail of phages to be taken orally each day by household members prior to, or soon after, exposure to <em>Vibrio cholerae</em> to protect them from contracting the disease. We believe the phages should remain in the intestinal tract long enough to serve as a shield against the incoming cholera bacteria. Although this has only been <a href="https://doi.org/10.1038/ncomms14187">proven in animal models of cholera</a>, we hope that the phage cocktail will work similarly in humans. There are three advantages to using phages in this manner. </p>
<p>First, phages provide immediate protection. By acting fast, phages can eliminate the cholera bacteria from the gut in a targeted manner. That is important because cholera kills quickly.</p>
<p>Second, phages infect and kill multi-drug resistant strains of bacteria just as well as drug-sensitive ones. This is crucial since the cholera bacteria have become <a href="http://dx.doi.org/10.4102/ajlm.v7i2.778">multi-drug resistant</a> in many parts of the world due to <a href="https://doi.org/10.1016/S1473-3099(14)70780-7">widespread antibiotic use.</a> </p>
<p>Third, in contrast to antibiotics, which kill bacteria indiscriminately, phages are very specific and infect only their particular host species of bacteria. Thus, when using phages against a pathogen, they will not disrupt the good bacteria residing in and on our patients’ bodies which are part of the microbiome. In research in our lab <a href="http://doi.org/10.1038/ncomms14187">phages, called ICP1, ICP2 and ICP3,</a> which we are using, kill only <em>Vibrio cholerae</em> and should not disrupt the good bacteria in the intestinal tract. This is important because our good bacteria are essential for defending the body against other pathogens and vital for our general nutrition and health.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/274705/original/file-20190515-60567-qv0a58.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/274705/original/file-20190515-60567-qv0a58.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/274705/original/file-20190515-60567-qv0a58.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/274705/original/file-20190515-60567-qv0a58.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/274705/original/file-20190515-60567-qv0a58.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/274705/original/file-20190515-60567-qv0a58.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=504&fit=crop&dpr=1 754w, https://images.theconversation.com/files/274705/original/file-20190515-60567-qv0a58.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=504&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/274705/original/file-20190515-60567-qv0a58.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=504&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">People fill buckets with water from a well that is alleged to be contaminated water with the bacterium <em>Vibrio cholera</em>, on the outskirts of Yemen. Yemen’s raging two-year conflict has served as an incubator for lethal cholera.</span>
<span class="attribution"><a class="source" href="http://www.apimages.com/metadata/Index/Yemen-Times-of-Cholera/a1ac866ac46045b8b172c6b7e2e707ee/6/1">AP Photo/Hani Mohammed</a></span>
</figcaption>
</figure>
<h2>From test tube to product</h2>
<p>In collaboration <a href="https://en.wikipedia.org/wiki/Shah_M._Faruque">with</a> <a href="https://www.icddrb.org/index.php?option=com_content&view=article&id=4223&Itemid=2202&staffID=200">international</a> <a href="https://www.icddrb.org/index.php?option=com_content&view=article&id=4223&Itemid=2202&staffID=54">researchers</a>, we have been studying the cholera bacteria and its phages for over two decades at Tufts University, trying to uncover the details of how cholera spreads and how phages might affect its spread. The use of phages for prevention of cholera transmission was a natural outcome of this research, but by no means was it straightforward. </p>
<p>Development of our phage product required finding phages that <a href="https://doi.org/10.1038/ncomms14187">kill <em>Vibrio cholerae</em> in the intestinal tract</a>, having intimate knowledge of <a href="https://doi.org/10.1038/nature11927">how the phages infect</a> <a href="https://doi.org/10.1371/journal.ppat.1002917">the bacteria</a> and discovering how the bacteria become <a href="https://doi.org/10.7554/eLife.03497">resistant to the phages and how this affects their virulence</a>.</p>
<p>Our goal now is to test the phage cocktail in people during a cholera epidemic. Specifically, we need to determine if it is effective at preventing cholera transmission to family members in households where cholera strikes.</p>
<p>In this day and age, we need to change the paradigm of relying entirely on antibiotics to treat infections and develop other types of antimicrobial solutions. It’s time to bring phages in from the cold, and utilize them both for treating multi-drug resistant bacterial infections and in the prevention of infections.</p><img src="https://counter.theconversation.com/content/117058/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Andrew Camilli is a co-founder and scientific advisor of PhagePro, a company developing phage products to promote global health. He receives funding from the United States of America National Institutes of Health. </span></em></p><p class="fine-print"><em><span>Dr. Minmin Yen is the CEO of PhagePro, a phage startup that prioritizes global health. She receives funding from the National Institutes of Health. </span></em></p>Cholera kills fast, and outbreaks are common in war-torn regions and after natural disasters where clean water is scarce. A new strategy to prevent cholera infections is a ‘cocktail’ of live virus.Andrew Camilli, Professor of Molecular Biology & Microbiology, Tufts UniversityMinmin Yen, Research Associate of Molecular Microbiology, Tufts UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/850212017-10-11T09:33:38Z2017-10-11T09:33:38ZWhat Yemen can learn from the historical experience of cholera<p>As of October 1, <a href="http://www.emro.who.int/yem/yemeninfocus/situation-reports.html">771,945</a> people in Yemen have been <a href="http://www.aljazeera.com/news/2017/09/yemen-cholera-outbreak-hit-million-2018-170929140409261.html">infected with cholera</a> and <a href="http://www.emro.who.int/images/stories/yemen/Yemen_Cholera_Response_-_Daily_Epidemiological_Update_-_2017-09-30_1.pdf?ua=1">2,134</a> have died from the disease. The epidemic, rare on such a scale in contemporary times, reemerged as a formidable force last year due to Yemen’s ongoing civil war.</p>
<p>The Saudi Arabia-led war <a href="https://www.pri.org/stories/2016-03-25/young-yemeni-man-wants-you-know-how-war-changed-his-life">began in March 2015</a> and has caused a spiralling <a href="http://www.bbc.com/news/world-middle-east-40558828">7,000 new cholera cases per day</a>. This is an enormous public health crisis – and one that could be solved simply. Treatment only demands providing clean water, oral rehydration salts, and gloves.</p>
<p>These wartime conditions allow us to draw parallels with the historical experience of epidemic – after all, it is the massive displacement and conditions of war that have allowed the disease to reemerge and wreak destruction in Yemen. War has overcome the near eradication of cholera that modern advances in medicine and international public health organisations have allowed. So how did these advances come to pass and what can we learn from the historical experience of cholera? </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/189607/original/file-20171010-17691-175ybih.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/189607/original/file-20171010-17691-175ybih.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=402&fit=crop&dpr=1 600w, https://images.theconversation.com/files/189607/original/file-20171010-17691-175ybih.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=402&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/189607/original/file-20171010-17691-175ybih.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=402&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/189607/original/file-20171010-17691-175ybih.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=505&fit=crop&dpr=1 754w, https://images.theconversation.com/files/189607/original/file-20171010-17691-175ybih.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=505&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/189607/original/file-20171010-17691-175ybih.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=505&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A patient drinks oral rehydration solution in order to counteract cholera-induced dehydration, 1992.</span>
<span class="attribution"><span class="source">Wikimedia Commons</span></span>
</figcaption>
</figure>
<h2>Cholera imagined</h2>
<p>We first find mention of a disease that is recognisably cholera in the works of Arab-Islamic scholars, where it is known of as “heydain”. Around 900 CE, the physician Muhammad ibn al-Razi described cholera in the following way:</p>
<blockquote>
<p>It begins with nausea and diarrhoea, or one of the two, and when it reaches the stomach it goes on multiplying itself. The pulse fails, and the breathing is attenuated; the face and the nose become thin; the colour of the skin of the face is changed, and the countenance of the dead succeeds.</p>
</blockquote>
<p>Despite this long history, cholera was, in particular, a 19th century tragedy. The disease, which travels through water, thrived on the world’s multiplying population and increased mobility. During the first cholera pandemic (1817-1823), the disease travelled across the Persian Gulf from Bahrain along the Indian Ocean and to the Red Sea in Aden. Over the course of the century, multiple outbreaks of the disease quickly spread through burgeoning coastal cities, along rivers, and into commercial ports from Delhi to New York City. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/189608/original/file-20171010-17670-1rqys9y.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/189608/original/file-20171010-17670-1rqys9y.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/189608/original/file-20171010-17670-1rqys9y.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=748&fit=crop&dpr=1 600w, https://images.theconversation.com/files/189608/original/file-20171010-17670-1rqys9y.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=748&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/189608/original/file-20171010-17670-1rqys9y.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=748&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/189608/original/file-20171010-17670-1rqys9y.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=940&fit=crop&dpr=1 754w, https://images.theconversation.com/files/189608/original/file-20171010-17670-1rqys9y.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=940&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/189608/original/file-20171010-17670-1rqys9y.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=940&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">How to avoid the Cholera, 1848.</span>
<span class="attribution"><span class="source">Wikimedia Commons</span></span>
</figcaption>
</figure>
<p>The Arabian peninsula was particularly badly hit given the amount of trade and number of pilgrims travelling through the area, seeing several cholera epidemics during the mid-19th century. The disease wreaked havoc on the pilgrims who gathered in Mecca and Jeddah in 1828, 1831, 1835, 1865, 1881, and 1882. Of those, the Mecca pilgrimage was said to be the most horrific, with an <a href="https://books.google.de/books?id=HRwGkfyNv6AC&printsec=frontcover#v=onepage&q&f=false">estimated toll</a> of 30,000 deaths over the course of the 19th century. </p>
<p>Medical and public health practitioners such as physicians and midwives played a major role in reducing transmission in the period. These people and institutions were financed through religious taxes and charity, which provided more resources to directly treat patients.</p>
<h2>Public health reforms</h2>
<p>But it was the emergence of modern medicine, the improvements on sanitation, and the isolation of <em>Vibrio cholerae</em> in 1854 by Filippo Pacini that worked to drastically ameliorate cholera’s impact in the latter half of the century.</p>
<p>The repeated outbreaks also arguably led to the creation of the kinds of public health institutions that we take for granted today. The <a href="https://www.ncbi.nlm.nih.gov/pubmed/24412079">International Sanitary Convention</a> (ISC), which held its first conference in 1851 in Paris, was set up with the aim of ending the cholera pandemic. The ISC was a predecessor to the World Health Organisation (WHO), a body that was mostly represented by European actors along with the Ottoman central authority (based in Istanbul).</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/189603/original/file-20171010-17673-8b83jy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/189603/original/file-20171010-17673-8b83jy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=469&fit=crop&dpr=1 600w, https://images.theconversation.com/files/189603/original/file-20171010-17673-8b83jy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=469&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/189603/original/file-20171010-17673-8b83jy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=469&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/189603/original/file-20171010-17673-8b83jy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=589&fit=crop&dpr=1 754w, https://images.theconversation.com/files/189603/original/file-20171010-17673-8b83jy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=589&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/189603/original/file-20171010-17673-8b83jy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=589&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"><em>Vibrio cholerae</em>.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Cholera_bacteria_SEM.jpg">Wikimedia Commons</a></span>
</figcaption>
</figure>
<p>Although the cholera epidemic was still rampant on the Arabian peninsula during the early 20th century, with outbreaks in Mecca between 1908-1912, the disease was then nearly totally absent from the peninsula until it spread in Yemen in 1971 – following the aftermath of the last Yemeni civil war.</p>
<p>Yemen witnessed cholera outbreaks in the 19th century due to the free movement of people and a very limited understanding of the disease. But the conditions and ways that the disease spread was nowhere near as quick-paced and detrimental as they are in the current outbreak.</p>
<h2>Cholera today</h2>
<p>The human cost of cholera in Yemen today, as we have seen, is grave and growing. There are predictions that the disease could infect <a href="http://www.aljazeera.com/news/2017/09/yemen-cholera-outbreak-hit-million-2018-170929140409261.html">a million people by 2018</a>. The incidence and prevalence of cholera infection far exceeds the numbers from the 19th century and the current crisis in Yemen will set a record number of reported cases in the country. </p>
<p>What makes the current epidemic so pernicious is the way that war has exacerbated the disease despite advances in medicine and public health. The doctors and nurses working in the 19th century were not mired by the catastrophic conditions of modern war: massive military occupation, infrastructure meltdown, and political decimation.</p>
<p>The Yemeni government ceased providing money for the public health department in March 2016, shortly after war began. International organisations have provided the principle support, but the amount they can do is limited by their ability to carry out treatment during military sieges. Less than 50% of <a href="https://www.nytimes.com/interactive/2017/08/23/world/middleeast/yemen-cholera-humanitarian-crisis.html?mcubz=0&_r=0">hospitals in Yemen</a> are operational, with shortages of staff and supplies due to the ongoing conflict. But austerity and war have fractured the public health system. The 30,000 doctors, nurses, and other health care workers of Yemen have been working for the last ten months without pay. </p>
<p>The treatment for cholera is very simple, yet materials – when available – are obstructed from being distributed due to bombing. The arc of authoritarianism and foreign occupation in Yemen has resulted in the <a href="http://www.huffingtonpost.com/entry/59732867e4b0545a5c31004d">destruction of Yemen’s infrastructure</a>, leaving 14m people without access to clean water.</p>
<p>History provides a glimpse of the tragic past and demonstrates that it is through policy that we can help to correct the tragedies that continue to face Yemen. Cholera is preventable, but public health reform is nearly impossible under conditions of war. The historical trajectory of cholera shows that interventions lose their effect when the public systems are crippled – something we also need to bear in mind <a href="https://theconversation.com/cholera-fears-rise-following-atlantic-hurricanes-are-we-making-any-progress-83694">in relation to the increased extreme weather events</a> caused by climate change.</p><img src="https://counter.theconversation.com/content/85021/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Edna Bonhomme 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>771,945 have been infected.Edna Bonhomme, Postdoctoral Fellow, Max Planck Institute for the History of ScienceLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/842272017-09-25T16:58:33Z2017-09-25T16:58:33ZWhat’s driving multiple outbreaks of cholera in Nigeria<figure><img src="https://images.theconversation.com/files/187354/original/file-20170925-17375-owq8gy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A woman takes an oral cholera vaccine in a hospital. But cholera vaccines are not always effective and never long lasting. </span> <span class="attribution"><span class="source">REUTERS/Andres Martinez Casares</span></span></figcaption></figure><p>This year, 16 of Nigeria’s 36 states have experienced <a href="http://www.ncdc.gov.ng/reports/weekly">cholera outbreaks</a>. This has <a href="http://www.ncdc.gov.ng/reports/weekly">resulted in</a> 1,622 suspected cases of the disease and 33 deaths. This is a steady increase in cholera cases after a remarkable sharp decline, from a total of 5,301 cases (186 deaths) in 2015 to 768 cases and <a href="http://www.ncdc.gov.ng/reports/weekly">32 deaths in 2016</a></p>
<p>Lagos witnessed the last outbreak in <a href="http://www.ncdc.gov.ng/reports/15/2016-november-week-45">October 2016</a> but in the last couple of weeks there have been outbreaks in Nigeria’s Lagos, Kwara and Borno states.</p>
<p>Regional disparities in the death rates from cholera expose the different levels of emergency preparedness and health resources available. Understanding why this threat persists can help health authorities to reduce it, in Nigeria and elsewhere.</p>
<p>Cholera is an intestinal infection characterised by <a href="http://www.webmd.com/a-to-z-guides/cholera-faq#1">watery stool and diarrhoea</a>. It is caused by the Vibrio cholerae, a bacterium, which releases toxins in the human intestine. This toxin activates excess secretion of water from the intestinal lumen that often lead to severe dehydration and sometimes death. Conditions that can lead to outbreaks include a disruption in water supply, poor basic sanitation and poor hygiene. Infected people show symptoms within two to five days. They can spread the disease <a href="http://science.jrank.org/pages/1450/Cholera-Transmission-cholera.html">even when they are not ill themselves</a> by shedding the bacteria in their faeces. </p>
<p>As in other developing countries, <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3428179/">cholera outbreaks occur mainly during the rainy season in Nigeria</a> although they also sometimes occur in dry season. Flooding can cause septic tanks to contaminate surface water, especially open wells used for <a href="http://www.water-research.net/index.php/bacteria">drinking and food preparation</a>. Contaminated flood water from the rains can also flow to vegetables and fruits which, if not properly washed, can cause an outbreak. </p>
<p>Cholera outbreaks happen when groups of people share infected water or food. When this happens, many people will require help at the same time. Health facilities and resources are often inadequate and ill-prepared to deal with such pressure. </p>
<p>The outbreaks in different parts of Nigeria are often driven by different factors. What they all point to, however, is that the country has not yet taken sufficient steps to address the “epidemiological triangle” that drives cholera outbreaks – host, agent and environmental factors. This includes early detection, better and stronger sanitation infrastructure that can withstand heavy rains as well as basic health infrastructure.</p>
<h2>The outbreaks and what caused them</h2>
<p>Lagos is the commercial centre of the country, with a densely settled population of <a href="http://worldpopulationreview.com/world-cities/lagos-population/">over 20 million people</a>. It lies along the coast and is prone to <a href="http://www.ncfnigeria.org/about-ncf/item/81-lagos-ncf-call-for-actions-to-save-coastal-areas">flooding</a>. Despite the enormous efforts put into strengthening its primary health care system, it <a href="https://www.vanguardngr.com/2017/07/diarrhoea-outbreak-lagos-2-dead-25-quarantined/">recorded 27</a> suspected cases of cholera and two deaths in July 2017. The outbreak has been attributed to heavy rainfall which eroded water sources, and <a href="http://www.informationng.com/2017/07/cholera-outbreak-lagos-2-persons-killed-25-others-hospitalised.html">to people getting help too late</a>. </p>
<p>To reduce the number of outbreaks in the future, Lagos must tackle the factors that cause flooding. It must also take decisive steps to relocate residents from the most flood prone areas and improve on environmental sanitation and public health campaigns.</p>
<p>Kwara State recorded 17 deaths from over 1,000 suspected cases. Health authorities there attributed the outbreak to <a href="http://thenewsnigeria.com.ng/2017/06/kwara-confirms-cholera-outbreak/">contaminated fruit consumed to break the Ramadan fast</a>. In 2011, 12 deaths were recorded from cholera outbreak and although the health authorities were silent on the cause, the residents blamed it on <a href="https://www.dailytrust.com.ng/news/health/cholera-outbreak-claims-over-12-in-kwara/200744.html">heaps of refuse that had not been removed</a>. The state’s growing population seems to have surpassed its <a href="https://www.thecable.ng/cholera-kwara-environmentalist-perspective">waste disposal infrastructure</a> </p>
<p>Borno State recorded the most serious outbreak of the three states. This northeastern state is the epicentre of the battle against the Islamic militant group Boko Haram. The outbreak affected the camp set up to accommodate people who had been displaced by the conflict. About 20,000 people are sheltered in this camp on the outskirts of Maiduguri, the Borno capital. The camp is overcrowded and <a href="https://www.vanguardngr.com/2017/09/14-people-die-cholera-borno/">lacks good amenities</a>. People there are poorly nourished and don’t have clean drinking water and sanitation.</p>
<p>Conflicts usually result in the destruction of infrastructure and disruption of services. This has worsened the situation in Borno, which already lagged behind other parts of Nigeria in <a href="http://www.unocha.org/nigeria/about-ocha-nigeria/about-crisis">social development</a>. Health facilities are poorly equipped and staffed, and women in particular have low levels of education which usually means lower earnings, poor choices, slow reaction to illnesses and <a href="https://www.ahrq.gov/professionals/education/curriculum-tools/population-health/zimmerman.html">low problem solving abilities</a>. These factors add to the risk of disease outbreaks and deaths. </p>
<h2>Why cholera endures</h2>
<p>It has been difficult to eradicate cholera because of the “epidemiological triangle” of host, agent and environmental factors. </p>
<p>Humans are the hosts. They carry and spread the disease. A person who has received treatment and is healthy again is still capable of spreading the infection to others. Vaccines are <a href="http://www.who.int/mediacentre/factsheets/fs107/en/">not very effective or long-lasting</a>. </p>
<p>Vibrio cholerae is the agent. It is ingested from contaminated food or water. The organisms that survive the stomach’s acidity travel to the small intestine of the human host, where they multiply. The bacteria <a href="https://www.ncbi.nlm.nih.gov/books/NBK8407/">attach to the mucous membrane of the intestines and can stay</a> there for years.</p>
<p>The environmental factors include poor access to clean, safe water and the lack of basic sanitation facilities. </p>
<p>To prevent and wipe out cholera, it’s necessary to interrupt the host-agent-environment relationship. This can be achieved through more effective vaccines, improved host immunity, water chlorination and better ways of disposing of sanitary waste. </p>
<p>In poor countries, the lack of standard infection prevention and control in health facilities adds to the risk of <a href="http://www.who.int/csr/resources/publications/4EPR_AM2.pdf">diseases spreading</a>. Health workers need to be continuously trained to detect, correctly diagnose and manage cases of cholera in a safe and effective manner. </p>
<p>Eradicating cholera and other diarrhoeal diseases in Nigeria will require a multi-sectoral approach. The ministries of water resources, rural development, urban planning and health must contribute, and government must show the political will to invest in infrastructure as well as health sector development.</p><img src="https://counter.theconversation.com/content/84227/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Doyin Ogunyemi 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>Many states in Nigeria are reeling from cholera outbreaks. They need better health and sanitation infrastructure to disrupt transmission of the bacteria which cause the disease.Doyin Ogunyemi, Public Health Physician and Lecturer, College of Medicine, University of LagosLicensed as Creative Commons – attribution, no derivatives.