tag:theconversation.com,2011:/global/topics/microcephaly-24434/articlesMicrocephaly – The Conversation2021-09-21T10:44:18Ztag:theconversation.com,2011:article/1678332021-09-21T10:44:18Z2021-09-21T10:44:18ZCommon pesticide may have made the Zika epidemic worse – new research<p>Before Covid, there was Zika. In 2015, the number of babies born in Brazil with small heads and brains – a condition known as microcephaly – suddenly increased dramatically. The severe deformities left the children disabled for life, and caused intense global concern.</p>
<p>These cases of microcephaly were soon shown to be caused by pregnant women being <a href="https://www.sciencedirect.com/science/article/pii/S1473309916303188?via%3Dihub">infected with the mosquito-borne Zika virus</a>. The virus infects and kills cells that form the brain, hampering its proper development.</p>
<p>But the impact was not universal – certain regions in north-eastern Brazil saw <a href="https://www.nature.com/articles/nature.2016.20309">far more cases of microcephaly than others</a>.</p>
<p>Scientists began to question whether other factors might be at play that intensified the epidemic in some places. Not long after, they focused their attention on <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5760164/#:%7E:text=Of%20particular%20note%20is%20that,been%20shown%20to%20cause%20microcephaly">pyriproxyfen</a>, a globally approved pesticide used against household insects in agriculture – including mosquitoes. Pyriproxyfen was used intensively in the regions with the highest numbers of microcephaly cases.</p>
<p>Now, in <a href="https://www.sciencedirect.com/science/article/pii/S0269749121012367?via%3Dihub">a new study</a>, we have shown that pyriproxyfen could indeed exacerbate the already severe effects the Zika virus has on foetal brain development.</p>
<h2>Pyriproxyfen and Zika</h2>
<p>In late 2014, pyriproxyfen was introduced to drinking water throughout Brazil to control the <em>Aedes aegypti</em> mosquito population, which spreads the Dengue and Zika viruses.</p>
<p>But the insecticide is known to accumulate in the environment for years, eventually finding its way into the human body. So to prevent potential side-effects, the <a href="https://www.who.int/water_sanitation_health/dwq/chemicals/pyriproxyfenvector.pdf">World Health Organisation</a> had recommended the daily intake of pyriproxyfen should not exceed 0.3 mg/L for an average adult, and concentrations in drinking water should be lower than 0.01 mg/L.</p>
<p>As babies and foetuses generally absorb or accumulate more chemicals than adults, they can be at greater risk. And because there was a strong geographical overlap between the use of pesticides and microcephaly cases, even these small doses raised issues concerning safety.</p>
<p><a href="https://www.sciencedirect.com/science/article/pii/S1473309917307272?via%3Dihub">Epidemiological</a> and <a href="https://link.springer.com/article/10.1007/s11356-020-10517-5">experimental</a> studies have since delivered contradictory results regarding whether or not pyriproxyfen was implicated in the disease outbreak. But in our recently published study, we discovered that pyriproxyfen impairs thyroid hormone signalling in the brain, modifying crucial processes for its proper development.</p>
<h2>How pyriproxyfen affects brain development</h2>
<p>Thyroid hormone is an important molecule that helps shape the foetal brain. Without it, the brain doesn’t grow as it’s supposed to, leaving affected children with learning difficulties for life.</p>
<p>In the lab, we house genetically modified tadpoles that emit green fluorescence when exposed to thyroid hormone. More thyroid hormone means more green signal, indicating the hormone is active in the tadpoles’ cells.</p>
<p>When we exposed our tadpoles to pyriproxyfen, the green signal dropped dramatically. This demonstrated that the pesticide blocks thyroid hormone action.</p>
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<img alt="" src="https://images.theconversation.com/files/414332/original/file-20210803-25-14b0hxc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/414332/original/file-20210803-25-14b0hxc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/414332/original/file-20210803-25-14b0hxc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/414332/original/file-20210803-25-14b0hxc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/414332/original/file-20210803-25-14b0hxc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/414332/original/file-20210803-25-14b0hxc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/414332/original/file-20210803-25-14b0hxc.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">
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<span class="caption">Genetically modified tadpoles emit green fluorescence when exposed to thyroid hormone (T3 in the image). When they were simultaneously exposed to pyriproxyfen, the fluorescent signal dropped significantly, showing the insecticide blocks thyroid hormone action.</span>
<span class="attribution"><span class="source">Petra Spirhanzlova, MNHN</span></span>
</figcaption>
</figure>
<p>One of the most important roles of thyroid hormone is to generate a balanced amount of nerve cells and their supporting cells, known as glia. Together, they form the essential building blocks of the brain.</p>
<p>Since pyriproxyfen blocks normal thyroid hormone action, we thought it might affect the generation of neurons and glial cells too. To investigate this, we used stem cells cultured from mouse brains, and exposed them to increasing doses of the pesticide.</p>
<p>The findings were clear: the higher the dose, the fewer cells were generated, and the more they died, producing an unbalanced proportion of nerve cells and glia.</p>
<p>The brains of the exposed tadpoles in our study did not develop normally, and made them behave unnaturally. Underlying these changes were altered expression patterns of a number of genes.</p>
<p>A key player in this was the gene <em>Msi1</em>, which encodes a protein called Musaschi-1. The Zika virus <a href="https://doi.org/10.1126/science.aam9243">uses this protein</a> to replicate and infect other cells, and we knew from <a href="https://www.sciencedirect.com/science/article/pii/S1934590912001737?via%3Dihub">previous studies</a> that more thyroid hormone resulted in less Musaschi-1.</p>
<p>Not surprisingly, the cells that survived pesticide exposure contained much more of the protein due to blocked thyroid hormone action. That’s why we hypothesised that, through increasing Musaschi-1, pyriproxyfen could allow the virus to replicate faster.</p>
<p>To test this, we infected exposed stem cells with the Zika virus and found that the transcription of key genes was altered compared to when they were infected with the virus alone and not exposed to the pesticide. Although we didn’t observe higher infection rates, it’s still possible that pesticide exposure could aggravate hampered brain development. That can worsen the impact the virus has on a child’s later-life intellectual capacities, and requires further investigation.</p>
<h2>Regulating pesticides</h2>
<p>This is not the first time a pesticide has been shown to alter the course of a disease.</p>
<p>For example, individuals with higher amounts of another chemical that disrupts the endocrine system, perfluorobutanoic acid, in their blood, are at risk of a <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0244815">more severe course of Covid-19</a>.</p>
<p>But for many other ubiquitous pesticides to which we are continuously exposed in our daily life, we have no clue as to how they affect us, and whether they interact with viral diseases.</p>
<p>We need better testing protocols for pesticides to obtain more solid data to inform health policies and decision makers.</p>
<p>As for pyriproxyfen, Europe is not proposing to use it at concentrations advised by the World Health Organization, but <a href="http://www.fao.org/faolex/results/details/en/c/LEX-FAOC198465/">recently reauthorised it</a>.</p>
<p>Our study emphasises again how little we know about the harmful effects of pesticides on human health, notably on brain development, but also the natural environment as a whole.</p><img src="https://counter.theconversation.com/content/167833/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Pieter Vancamp has received funding from the Foundation for Medical Research and the European Thyroid Association.</span></em></p><p class="fine-print"><em><span>Barbara Demeneix ne travaille pas, ne conseille pas, ne possède pas de parts, ne reçoit pas de fonds d'une organisation qui pourrait tirer profit de cet article, et n'a déclaré aucune autre affiliation que son organisme de recherche.</span></em></p>A new study shows that the pesticide pyriproxyfen – widely used in Brazil during the Zika outbreak of 2015 – could disrupt thyroid hormones and thus affect brain development in children.Pieter Vancamp, Post-doctorant, Muséum national d’histoire naturelle (MNHN)Barbara Demeneix, Professor Physiology, Endocrinology, Muséum national d’histoire naturelle (MNHN)Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1086602018-12-14T11:46:17Z2018-12-14T11:46:17ZTrump administration ban on NIH use of fetal tissue should worry all scientists<figure><img src="https://images.theconversation.com/files/250477/original/file-20181213-178576-32dhei.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Researchers studying Alzheimer's disease use fetal tissue for their experiments.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/alzheimers-disease-on-mri-3-664361182">Atthapon Raksthaput/Shutterstock.com</a></span></figcaption></figure><p>Throughout history, politicians have restricted or outright banned certain areas of scientific or medical research based on moral or ethical grounds. In some cases, these measures were justified and prevented <a href="https://www.cdc.gov/tuskegee/timeline.htm">unethical</a> <a href="https://www.hhs.gov/ohrp/regulations-and-policy/belmont-report/read-the-belmont-report/index.html">human</a> or <a href="https://history.nih.gov/research/downloads/nuremberg.pdf">animal</a> research. In others, the bans could be seen as misguided and delaying medical advances.</p>
<p>The use of human fetal tissue for research purposes has been highly contentious and tightly regulated, given that access to this tissue is directly associated with a woman’s right to choose an abortion since the tissue is procured from human fetuses. In 1993, <a href="https://www.guttmacher.org/gpr/2001/02/human-embryo-and-fetal-research-medical-support-and-political-controversy">Congress approved the use of federal funds for fetal tissue research</a>. Recently, prompted by <a href="https://www.sba-list.org/wp-content/uploads/2018/09/Group-Letter-to-Azar-FDA-and-fetal-tissue-FINAL-with-Signatures.pdf">anti-abortion groups</a> and <a href="https://chrissmith.house.gov/uploadedfiles/2018-09-17_-chs-hartzler-walker_letter_on_fda_fetal_tissue_contract.pdf">supported by 85 Republican members of Congress</a>, <a href="https://www.hhs.gov/about/news/2018/09/24/statement-from-the-department-of-health-and-human-services.html">the Trump administration </a> <a href="http://doi.org/10.1126/science.aaw3165">banned the acquisition</a> of human fetal tissue for research conducted by scientists employed by the National Institutes of Health. In addition, several states, <a href="https://www.guttmacher.org/image/2016/state-laws-fetal-tissue-donation-and-research">including Indiana, Kentucky, Ohio and Oklahoma</a>, have banned the use of human fetal tissue in research at the state level. </p>
<p><a href="http://www.chp.edu/research/areas/infectious-diseases/coyne-lab/areas">I am a scientist</a> who studies the impact of viral infections on fetal development and postnatal health, with the goal of improving the well-being of infants and children. I believe that the highly politicized nature of human fetal tissue research and the ever-growing government restrictions on the use of this tissue will stymie scientific discovery and hinder the development of new treatments to reduce the burden of human disease.</p>
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<img alt="" src="https://images.theconversation.com/files/250338/original/file-20181212-110249-1nwxoxz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/250338/original/file-20181212-110249-1nwxoxz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/250338/original/file-20181212-110249-1nwxoxz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/250338/original/file-20181212-110249-1nwxoxz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/250338/original/file-20181212-110249-1nwxoxz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/250338/original/file-20181212-110249-1nwxoxz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/250338/original/file-20181212-110249-1nwxoxz.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">Fetal tissue is essential for understanding how the virus causes birth defects in the developing fetus.</span>
<span class="attribution"><a class="source" href="http://www.apimages.com/metadata/Index/Brazil-Zika-Kids-Boy-in-Bucket/5e23f5ea2be84f599be4d80a1ad07801/3/0">AP Photo/Felipe Dana</a></span>
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<h2>Uses for fetal tissue</h2>
<p>The use of human fetal tissue in medical research has resulted in many seminal discoveries that have directly improved human health. Several vaccines, including those against chickenpox (varicella) and Rubella virus, have saved millions of human lives and were <a href="https://www.chop.edu/centers-programs/vaccine-education-center/vaccine-ingredients/fetal-tissues">manufactured from viruses initially grown in human fetal-derived cells</a>.</p>
<p>Fetal tissue has also been used to develop <a href="http://doi.org/10.1146/annurev-virology-101416-041703">“humanized” mouse models of disease</a>. These models involve the transfer of specific cells isolated from human fetal tissue into mice that lack an immune system, thus allowing for studies in human cells in the context of a whole animal model. These models have proven invaluable for <a href="http://doi.org/10.1146/annurev-virology-101416-041703">revealing the biology of HIV infection</a> and for testing novel anti-HIV therapeutics. </p>
<p><a href="https://www.nytimes.com/2016/02/02/health/zika-virus-world-health-organization.html">The recent outbreak</a> of <a href="https://www.cdc.gov/zika/index.html">Zika virus</a>, which causes a variety of malformations including microcephaly in a developing fetus, underscored the necessity to perform studies in human fetal tissue to identify how the virus is transmitted from the infected mother to her developing fetus. The human placenta, which forms the sole interface between the mother’s and her fetus’s blood throughout pregnancy, is structurally distinct from that of most small animal laboratory models, like the mouse or rat. Thus human-derived fetal tissue is essential to study the biology of Zika virus. </p>
<p>Outside of infectious disease research, <a href="http://doi.org/10.4103/1673-5374.241459">fetal tissue has provided insights into human neurological diseases</a> such as Alzheimer’s, which is expected to affect more than <a href="https://www.alz.org/alzheimers-dementia/facts-figures">5 million Americans over the age of 65 by 2050</a>.</p>
<p>Scientists can procure tissue from different sources, including mechanisms within a given institution or through a third-party vendor. However, <a href="https://www.guttmacher.org/gpr/2001/02/human-embryo-and-fetal-research-medical-support-and-political-controversy">it is illegal to profit </a> from the sale of human fetal tissue, a principle which was passed into law in 1993. </p>
<h2>Scientists become entangled in the fetal tissue debate</h2>
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<img alt="" src="https://images.theconversation.com/files/250336/original/file-20181212-110243-1qpisfz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/250336/original/file-20181212-110243-1qpisfz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=324&fit=crop&dpr=1 600w, https://images.theconversation.com/files/250336/original/file-20181212-110243-1qpisfz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=324&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/250336/original/file-20181212-110243-1qpisfz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=324&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/250336/original/file-20181212-110243-1qpisfz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=407&fit=crop&dpr=1 754w, https://images.theconversation.com/files/250336/original/file-20181212-110243-1qpisfz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=407&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/250336/original/file-20181212-110243-1qpisfz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=407&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">Activists dressed as characters from ‘The Handmaid’s Tale’ leave the Texas Capitol Rotunda as they protest SB8, a bill that would require health care facilities, including hospitals and abortion clinics, to bury or cremate any fetal remains, rather than donate aborted fetal tissue to medical researchers.</span>
<span class="attribution"><a class="source" href="http://www.apimages.com/metadata/Index/Texas-Legislature/30efda175f6e43d9ad86d0e204560f0d/4/0">AP Photo/Eric Gay</a></span>
</figcaption>
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<p>Scientists who use human fetal tissue in their research have themselves become subject to intense government scrutiny. During the Obama administration, Republican House member Marsha Blackburn from Tennessee – who has since been elected to the U.S. Senate – chaired a “<a href="https://archives-energycommerce.house.gov/select-investigative-panel">Select Investigative Panel</a> on Infant Lives” special committee that looked into the use of fetal tissue in research. </p>
<p>This committee was formed in direct response to heavily <a href="https://www.washingtonpost.com/politics/undercover-video-shows-planned-parenthood-exec-discussing-organ-harvesting/2015/07/14/ae330e34-2a4d-11e5-bd33-395c05608059_story.html">edited undercover videos</a> that purported to show the unethical sale of human fetal tissue by Planned Parenthood. In addition to investigating the sale of fetal tissue by Planned Parenthood and other suppliers, the panel also subpoenaed researchers to testify on the use of fetal tissue in their own studies. </p>
<p>The committee released its <a href="https://archives-energycommerce.house.gov/sites/republicans.energycommerce.house.gov/files/documents/Select_Investigative_Panel_Final_Report.pdf">final report</a> at the end of 2016 after an expensive 15-month investigation. Despite clear scientific evidence to the contrary, the <a href="http://www.sciencemag.org/news/2017/01/fact-checking-congress-s-fetal-tissue-report">committee concluded</a> that no significant medical advancements had ever resulted from the use of human fetal tissue and that the NIH should no longer fund any research that utilizes fetal tissue. </p>
<p>The committee instead advocated the use of other research models, such as cell lines isolated from cancerous tumors or rodent-based models, despite the fact that many of these systems do not accurately mimic key aspects of human biology and disease. In anticipation of possible restrictions imposed on human fetal research, the NIH is investing US$20 million toward <a href="http://time.com/5475726/human-fetal-tissue-research/">development of alternative models</a> and approaches. </p>
<h2>Scientific research requires freedom</h2>
<p>Many scientists might assume that they will be unaffected by these government restrictions. However, many commonly used cell lines, such as human embryonic kidney cells, which are used in research labs to produce protein, fall under the blanket definition of fetal tissue. Given their fetal origin, their use could be banned. </p>
<p>Moreover, as a scientist, I fear that this type of government regulation of scientific inquiry based on political nonscientific grounds sets a precedent that could affect every scientist in academia, industry or government. Indeed, the current administration ban on fetal tissue for researchers at the NIH could eventually spread to include all NIH-supported scientists. In this scenario, most research involving human fetal tissue would be stopped throughout the United States. </p>
<p>Scientific discovery requires freedom, and I believe it should be exempt from external political influences. This concept was established in the 1940s, when academic institutions began awarding tenure and the American Association of University Professors stated “<a href="https://www.aaup.org/report/1940-statement-principles-academic-freedom-and-tenure">The common good depends upon the free search for truth and its free exposition</a>.” </p>
<p>In my opinion, banning or restricting research with human fetal tissue derived from elective terminations has no moral or ethical purpose and serves only to fit a political agenda. All scientists should be alarmed by the actions of our government.</p><img src="https://counter.theconversation.com/content/108660/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Carolyn Coyne receives funding from the NIH.</span></em></p>The Trump administration has banned NIH researchers from using fetal tissue. The tissue is an essential tool for scientists investigating diseases ranging from Alzheimer’s to Zika virus infections.Carolyn Coyne, Professor of Pediatrics, University of PittsburghLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/826182017-09-06T15:46:58Z2017-09-06T15:46:58ZWhatever happened to the Zika virus?<figure><img src="https://images.theconversation.com/files/184898/original/file-20170906-9875-1cd666g.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://www.shutterstock.com/image-photo/mosquito-sucking-blood-human-hand-toned-588293429">Shutterstock</a></span></figcaption></figure><p>If I asked if you’d heard of the <a href="http://www.nhs.uk/Conditions/zika-virus/Pages/Introduction.aspx">Zika</a> virus before 2015, chances are the answer would be no. In fact, many scientists working in the field of mosquito-transmitted diseases probably wouldn’t have heard of it. If they had, it would have been regarded as something obscure from the history books.</p>
<p>First <a href="http://www.who.int/emergencies/zika-virus/timeline/en/">discovered in Uganda</a> in the late 1940s, documented infections were rare until 2007 when the first large outbreak in humans occurred on the Pacific Island of Yap in Micronesia. The team of scientists involved in the initial discovery included the University of Glasgow’s Professor <a href="http://www.universitystory.gla.ac.uk/biography/?id=WH2116&type=P">Alexander John Haddow</a>, and the university’s archives hold 25 years of Haddow’s data which is now being meticulously <a href="https://universityofglasgowlibrary.wordpress.com/2017/04/11/zika-cataloguing-project-first-bite/">catalogued</a> as part of project funded by the <a href="https://wellcome.ac.uk/what-we-do">Wellcome Trust</a>.</p>
<p>Further Zika virus outbreaks occurred during 2013-2014 on other Pacific islands – French Polynesia, Easter Island, the Cook Islands and New Caledonia – before it reached the Americas in 2015. What exactly led to this explosive outbreak is still not completely understood, but the virus suddenly became a very real health concern requiring urgent research.</p>
<h2>Caught on the hop</h2>
<p>The outbreak in 2015 caught researchers and public health officials on the back foot as very little had been done to understand it since its initial discovery. However, the rate at which it spread, coupled with its association with neurological conditions like <a href="http://www.nhs.uk/conditions/guillain-barre-syndrome/Pages/Symptoms.aspx">Guillain-Barré syndrome</a> (muscle weakness caused by the immune system attacking the <a href="http://www.bbc.co.uk/science/humanbody/body/factfiles/peripheralnervoussystem/peripheral_nervous_system.shtml">peripheral nervous system</a>), and birth defects such as <a href="https://www.cdc.gov/zika/hc-providers/infants-children/zika-syndrome-birth-defects.html">congenital Zika syndrome</a> (disorders caused by the infection) and <a href="https://www.cdc.gov/ncbddd/birthdefects/microcephaly.html">microcephaly</a> (decreased brain development and smaller head size in babies) made it a frightening disease.</p>
<p>Currently, the most effective method of preventing virus transmission is sustainable control of mosquito populations. This is achieved by eradicating standing water sources used as breeding sites and the use of insecticides and repellents, combined with public education programmes.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/184899/original/file-20170906-8282-1jcyel.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/184899/original/file-20170906-8282-1jcyel.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/184899/original/file-20170906-8282-1jcyel.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/184899/original/file-20170906-8282-1jcyel.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/184899/original/file-20170906-8282-1jcyel.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/184899/original/file-20170906-8282-1jcyel.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/184899/original/file-20170906-8282-1jcyel.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The most effective way of dealing with the Zika virus at the moment is destroying mosquito breeding grounds with insecticides.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/korat-thailand-march-22-2016-unidentified-394662079">Shutterstock</a></span>
</figcaption>
</figure>
<p>Recent outbreaks of Zika virus and <a href="https://www.cdc.gov/chikungunya/index.html">chikungunya virus</a> (which causes rash, fever and severe joint pain) – both transmitted by the <a href="http://www.who.int/denguecontrol/mosquito/en/">Aedes mosquito</a> – have raised concern in the US. Like other mosquito-transmitted viruses, these infections are seasonal and cases rise and fall with the activity of mosquito populations.</p>
<p>In southern American states like Florida and Texas, mosquito season begins in early February/March and peaks at the height of the summer during July/August. With high humidity and temperatures, the tropical climate in these states is particularly conducive to mosquito breeding and egg laying.</p>
<p>Brownsville, Texas, and Miami-Dade County, Florida, have previously been designated “<a href="https://www.cdc.gov/zika/geo/domestic-guidance.html">cautionary areas</a>” where local mosquito-borne Zika virus transmission has been identified, although this status was lifted last month, meaning there are no longer any precautionary travel recommendations in place for these areas.</p>
<p>Further north, many eastern and midwestern cities have seen an increase in the average annual length of their mosquito season over the last couple of decades due to increasing local temperatures. The growing number of days suitable for mosquito breeding increases the risk of cases of several mosquito-transmitted diseases.</p>
<h2>Sex and other routes of transmission</h2>
<p>However, the concern over Zika virus infections is not limited to mosquito bites, as <a href="https://www.cdc.gov/zika/prevention/sexual-transmission-prevention.html">sexual contact</a> is also a viable route of transmission, as are blood transfusions, organ transplants and mother-to-baby transmission.</p>
<p>Sexual transmission has not previously been reported for other mosquito-transmitted viruses and is yet another twist for experts trying to get a handle on this virus. Although these are not the main routes of transmission, they increase the risk of virus infections in areas where mosquitoes are absent.</p>
<p>In November 2016, the <a href="http://www.who.int/about/en/">World Health Organisation</a> (WHO) declared an end to the Zika <a href="http://www.who.int/ihr/procedures/pheic/en/">Public Health Emergency of International Concern</a> which had been in place since February 2016. It stated that downgrading the response did not reduce the importance of the virus and pledged a long-term response to Zika virus control, emphasising that the crisis was not over.</p>
<p>Local surveillance is still ongoing and precautions should still be taken when travelling to and from areas were the virus is being transmitted, in particular by pregnant women. Wearing long-sleeved clothing and insect repellent is prudent in endemic areas and consistent and careful condom use or sexual abstinence will prevent spread by sexual contact.</p>
<p>A significant sum of research money has been made available to scientists across the globe to figure out as much as possible about this extraordinary virus. To facilitate the rapid generation of information, multiple cross-discipline collaborations have been formed and previously untapped alliances established, allowing fundamental advances such as disease modelling, virus evolution tracking and epidemiological surveillance to be made with unprecedented speed.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/184901/original/file-20170906-9871-1m3faky.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/184901/original/file-20170906-9871-1m3faky.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/184901/original/file-20170906-9871-1m3faky.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/184901/original/file-20170906-9871-1m3faky.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/184901/original/file-20170906-9871-1m3faky.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/184901/original/file-20170906-9871-1m3faky.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/184901/original/file-20170906-9871-1m3faky.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The gravest effect of Zika is children born with microcephaly – small heads and reduced brain development.</span>
</figcaption>
</figure>
<h2>A safe and effective vaccine</h2>
<p>Leading researchers and public health organisations from around the world have joined forces on a unique scale to better understand Zika virus and the clinical symptoms resulting from infection. Prime among their tasks has been the development of a safe and effective vaccine – particularly to protect an unborn child against infection. </p>
<p>Several potential vaccines are currently under development, with some showing promise in phase one human trials. Single dose, live-virus vaccines are proving effective but are not suitable for pregnant women, while non-replicating virus vaccines may be safer for expectant mothers, but multiple doses are required.</p>
<p>Unfortunately, to make matters more complicated, vaccine development needs to take other Aedes mosquito-transmitted viruses, <a href="http://www.nhs.uk/Conditions/dengue/Pages/Introduction.aspx">dengue fever</a> and chikungunya, into account. These have similar symptoms, circulate in the same areas and are often confused, resulting in misdiagnosis.</p>
<p>Previous infections can have an effect on the efficacy of a vaccine and need to be taken into account. A suitable product for market is still a good way off and it will take more time and effort to develop sufficient pharmaceuticals that can be delivered to the vulnerable populations that need them most.</p>
<p>Thanks to increased <a href="http://geography.org.uk/resources/videocasts/urbanisation/">urbanisation</a> and <a href="http://www.economicsonline.co.uk/Global_economics/Globalisation_introduction.html">globalisation</a>, including widespread travel and transport of goods and a changing climate, it is likely that mosquito-transmitted diseases will continue to have the means to spread.</p>
<p>The growing links between societies around the globe makes universal public health an important worry for developed, as well as developing countries. A coordinated response at local community level is vital to limit the global spread of emerging and reemerging mosquito-borne diseases.</p>
<p>So long as socio-economic conditions facilitate mosquito life cycles, the risk of importing viruses from endemic areas is a viable threat we should all be prepared for.</p><img src="https://counter.theconversation.com/content/82618/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Claire Donald receives funding from the Medical Research Council of the UK. </span></em></p>The World Health Organisation has pledged a long-term response to controlling the Zika virus because the threat is far from overClaire Donald, Post-doctoral Research Assistant, University of GlasgowLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/803432017-07-05T11:03:42Z2017-07-05T11:03:42ZUnderstanding Zika’s silent presence in Africa is key to tackling the next epidemic<figure><img src="https://images.theconversation.com/files/176799/original/file-20170704-808-78ov9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Finding Zika's roots can help contain the virus.</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>The Zika virus emerged in northeast Brazil in early 2015. By September the first cases of infants born with microcephaly had been <a href="https://www.cdc.gov/mmwr/volumes/65/wr/mm6503e2.htm">reported in 8 of 26 Brazilian states</a>. Microcephaly is a birth defect where the baby’s head is smaller compared with babies of the same age and sex. Babies with this condition often have smaller and usually have less <a href="https://www.cdc.gov/ncbddd/birthdefects/microcephaly.html">developed brains</a>. </p>
<p>The virus spread rapidly throughout South and Central America and the Caribbean. <a href="http://www.who.int/emergencies/zika-virus/situation-report/25-august-2016/en/">By 2016</a>, 20 countries or territories had reported microcephaly and other central nervous system malformations potentially associated with the Zika virus infection. This included Guillain-Barré Syndrome, a rare sickness of the nervous system which has been shown to be strongly <a href="http://www.who.int/emergencies/zika-virus/situation-report/25-august-2016/en/">associated with Zika</a>.</p>
<p>Zika came to global attention as a dangerous transmissible disease following the Brazil and South American outbreak of 2013. But the Zika virus didn’t originate in Brazil or even Micronesia where the <a href="http://apps.who.int/iris/bitstream/10665/249534/1/zikasitrep18Aug16-eng.pdf?ua=1">2007 outbreak</a> occurred. In fact, the virus was recognised in Africa in the 1940s although there were only sporadic reports on the continent after its discovery. </p>
<p>The question about whether the Zika virus was still present in Africa has continued to worry scientists. A recent study led by researchers from Harvard T.H. Chan School of Public Health answers this question and fills in a gap in the Zika history. It shows that the virus has been circulating silently in West Africa for the <a href="https://academic.oup.com/jid/article/doi/10.1093/infdis/jix182/3200349/Continued-Transmission-of-Zika-Virus-in-Humans-in?guestAccessKey=a76bf23c-8265-4410-b5f3-12394d1501b6">past two decades</a>.</p>
<p>This knowledge is important because the history of how a disease emerges, its incidence and distribution is necessary in determining the best possible treatment and control systems. It’s therefore critical that as much as possible is known about Zika in Africa before the next epidemic occurs. As we’ve learnt from the devastating West Africa Ebola outbreak, the threats of global health pathogens cannot be readily predicted. </p>
<h2>African and Asian Zika strains</h2>
<p>One of the questions that’s perplexed scientists is why the distinct features and abnormalities seen in the Zika epidemic in Latin America haven’t been seen in Africa. This despite the fact that for some time it’s been suspected that the Zika and related mosquito-borne viruses have been present on the continent.</p>
<p>Earlier genetic analysis has distinguished African and <a href="http://www.biorxiv.org/content/biorxiv/early/2016/09/19/075747.full.pdf">Asian Zika lineages</a> of the virus. One theory is that the Asian lineage was different from the African lineage, with the <a href="http://www.sciencedirect.com/science/article/pii/S1995764516307350">Asian Zika linked</a> to the more dramatic transmissibility and unique disease association seen in the 2015-16 epidemic of the Americas. </p>
<p>Recognition that the two lineages are distinct led scientists to begin to compare them. What they’ve found so far is that both viruses cause damage to <a href="https://www.elsevier.com/connect/why-does-zika-virus-infect-brain-cells-in-fetuses-but-not-adults">primitive brain cells</a>, induce brain injury <a href="http://www.nature.com/nature/journal/vnfv/ncurrent/full/nature18296.html">in mice</a> and in <a href="https://www.ncbi.nlm.nih.gov/pubmed/27162029">cerebral organoids</a> that mimic the early human brain. </p>
<h2>History of discovery</h2>
<p>The Zika virus was discovered in the Zika forest of Uganda during a study of the yellow fever virus which used sentinel <a href="http://www.who.int/emergencies/zika-virus/timeline/en/">rhesus monkeys in 1947</a>. The virus was later also found in a species of mosquitoes called Aedes africanus which was collected from the same site in 1948.</p>
<p>The <a href="http://www.who.int/emergencies/zika-virus/timeline/en/">first human Zika infections</a> occurred in Uganda, Tanzania and Nigeria between 1952 and 1954. Sporadic studies of mosquito and human infection were reported in West Africa in the 1960s-1970s but the clinical significance of the virus wasn’t appreciated at the time. </p>
<p>Between 1969 and 1983 Zika <a href="http://www.who.int/emergencies/zika-virus/timeline/en/">spread</a> to Asia, including India, Indonesia, Malaysia and Pakistan. In 2007 Zika emerged outside of Asia and Africa with an epidemic on Yap Island in the Pacific Ocean followed by a larger epidemic in French Polynesia in 2013-14 which spread to other countries in Oceania. An increase in Guillain-Barré Syndrome was also reported and linked to the Zika infection. </p>
<p>The classic clinical disease of Zika resembles that of other flaviviruses such as <a href="http://www.who.int/mediacentre/factsheets/fs117/en/">dengue virus</a>. Symptoms include fever, headache, conjunctivitis and a skin rash although distinguishing the multiple causes of fever can be difficult. </p>
<h2>Our research findings</h2>
<p>During our <a href="https://academic.oup.com/jid/article/doi/10.1093/infdis/jix182/3200349/Continued-Transmission-of-Zika-Virus-in-Humans-in?guestAccessKey=a76bf23c-8265-4410-b5f3-12394d1501b6">research</a> we surveyed samples from 387 febrile patients in Senegal and Nigeria collected over 24 years – from 1992-2016. The Nigerian samples were from HIV-infected patients cared for at the University of Jos Teaching Hospital. The Senegalese samples came from multiple HIV and malaria collaborative studies conducted by professors from Université Cheikh Anta Diop, in Dakar, Senegal. </p>
<p>The early response to Zika virus was found in 6.2% of the blood samples that were tested. The genetic code of the viruses from some patients was determined and it was found that they belonged to the African lineage, grouping with either the Nigerian or 1947 Ugandan sub-lineages. </p>
<p>Evidence that Zika has been silently circulating in West Africa for several decades is important because we need to know if the virus is also responsible for outbreaks and associated microcephaly in infants, or for other neurological diseases. </p>
<p>It’s possible that microcephaly and Guillain-Barré Syndrome aren’t being detected in Africa because virus infection levels are low and health care systems are poor. In the future better recognition of the associated disease and improved laboratory tests may plug this gap. In the meantime, studying the Zika virus in Africa will help us better understand its current status, the diseases it may cause and how we can prepare for the next outbreak.</p><img src="https://counter.theconversation.com/content/80343/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Phyllis Kanki receives research funding from the Centers for Disease Control and Prevention, Department of the Defense and the NIH. </span></em></p>The 2015 Zika outbreak in South America brought the virus to global attention. But tracing the history of the virus in West Africa can give clues to tackling future outbreaks.Phyllis Kanki, Professor of Immunology and Infectious Diseases, Harvard UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/724602017-02-09T09:11:52Z2017-02-09T09:11:52ZThe campaign to eradicate Zika has trampled over women’s rights<figure><img src="https://images.theconversation.com/files/156031/original/image-20170208-17341-hui0a0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Fumigation against the Zika-carrying mosquito in Guatemala. </span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/conred/24660687272/in/album-72157663537821689/">Coordinadora Nacional para Reducción de Desastres via Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span></figcaption></figure><p>The World Health Organisation <a href="http://www.bbc.co.uk/news/health-35459797">declared</a> that the Zika epidemic was an international emergency in February 2016. While the WHO <a href="http://www.who.int/mediacentre/news/statements/2016/zika-fifth-ec/en/">lifted the declaration</a> nine months later, the crisis is far from over. Zika, which <a href="https://theconversation.com/proving-that-the-zika-virus-causes-microcephaly-53716">has been linked</a> to various neurological and developmental conditions such as microcephaly and Guillain-Barré syndrome, has morphed into a long-term disease that the world will continually need to manage. </p>
<p>Zika has shown that in addition to causing death and suffering, epidemics cause enormous economic and social upheaval, and that public health crises often expose longstanding human rights crises, too. </p>
<p>The speed with which the Zika virus spread from its outbreak in Brazil on to <a href="http://reliefweb.int/report/world/zika-virus-outbreak-continues-one-year-after-global-emergency">over 70 countries</a> has been alarming. We know that Zika is transmitted by <em>aedes aegypti</em> mosquitoes, the same mosquitoes that transmit yellow fever, dengue and chikungunya. These mosquitoes breed where poor people lack adequate sanitation systems, for instance <a href="https://cdn2.sph.harvard.edu/wp-content/uploads/sites/13/2014/12/Barcellos-final.pdf">in much of Latin America</a>,</p>
<p>We also know that not all adults are exposed in the same way but that pregnant mother-to-child transmission poses high risks to the infant, including microcephaly. Economically disadvantaged segments of the population are at higher risk of exposure to Zika, of being infected, and of their children being born with microcephaly or other genetic conditions that require special care in the long term.</p>
<p>In Brazil, <a href="http://www.who.int/emergencies/zika-virus/situation-report/who-zika-situation-report-12-02-2016.pdf">more than 1.5m</a> people have been affected in the epidemic, mostly in the north east of the country. Since the outbreak, Brazil has logged more than <a href="http://www.npr.org/sections/goatsandsoda/2016/11/18/502616422/zika-no-longer-global-health-emergency-who-declares">2,000</a> confirmed cases of microcephaly compared to 147 cases in <a href="http://portalsaude.saude.gov.br/index.php/cidadao/principal/agencia-saude/21890-ministerio-da-saude-investiga-3-448-casos-suspeitos-de-microcefalia">2014</a>. </p>
<p>A large proportion of single parent families have been affected, the majority of which are headed by women. These households are more likely to experience perpetual cycles of poverty as a result of the economic shock of disease. In addition, where children are born with potentially disabling impairments they are often further isolated by limited support or social protection. In this context, Zika has also reinforced expectations that it will be women who will be responsibility for raising and caring for children affected by disabilities linked to the disease. This limits even further the opportunities women have to attend education programmes or look for formal employment. </p>
<h2>Rules of conception</h2>
<p>The UN <a href="https://academicimpact.un.org/content/human-rights-dimensions-zika#_ftnref2">High Commissioner for Human Rights</a> and the WHO reinforced the importance of women’s human rights in national responses to the Zika outbreak. Nevertheless, Zika gave way to a roll out of official declarations from ministries of health across Latin America telling women not to get pregnant. These echoed narrowly conceived and often ineffective public health campaigns of an earlier era in relation to <a href="http://www.npr.org/sections/goatsandsoda/2016/05/03/476601108/u-s-spent-1-4-billion-to-stop-hiv-by-promoting-abstinence-did-it-work">HIV/AIDS and abstinence</a> in Africa. </p>
<p>The US Center for Disease Control and Prevention, meanwhile, advised pregnant women to refrain from travelling to countries affected by the Zika virus. Most dramatically, health officials in El Salvador <a href="https://www.bostonglobe.com/magazine/2016/02/03/zika-and-trouble-with-public-health-directives/k9P4GIueJuQj3DImZDMmmO/story.html">urged women not to get pregnant until 2018</a>, while <a href="http://www.bbc.co.uk/news/world-latin-america-35388842">Colombia</a> called on women to delay pregnancy for six to eight months.</p>
<p>But shifting responsibility for the disease to women’s behaviour isolates the disease from other socio-economic factors that influence its transmission, such as sanitation or environmental issues. It means responses <a href="https://www.chathamhouse.org/publication/ia/gendered-human-rights-analysis-ebola-and-zika-locating-gender-global-health">have tended to focus</a> on the “immediate” healthcare problem, while the gender inequality that underpins the prevailing unhealthy conditions is considered “beyond” the capacity of public health interventions. </p>
<p>In Zika-affected countries, there are also high prevailing rates of <a href="http://www.paho.org/hq/index.php?option=com_content&view=article&id=8175%3Aviolence-against-women-in-latin-america-and-the-caribbean&catid=1505%3Asde-about-us&Itemid=1519&lang=en">sexual violence</a>, elusive contraception, teen pregnancies and lack of sexual education. <a href="https://www.guttmacher.org/media/nr/2014/09/17/sfp-sedgh-up.html">According to a study</a> published by the Guttmacher Institute in 2014, 56% of pregnancies in Latin American and the Caribbean are unintended, either because of lack of access to contraceptives or because of gender violence. </p>
<h2>Reproductive rights</h2>
<p>In a region where <a href="https://theconversation.com/zika-and-abortion-will-the-virus-prompt-latin-america-to-rethink-abortion-and-birth-control-55200">birth control is limited</a> and sexual violence is widespread, the debate on legalising abortion has also gained prominence during the Zika outbreak. Clandestine abortions are an unfortunate reality across Latin America. For poor women, this generally means unsafe abortions are a leading cause of maternal mortality. </p>
<p><a href="http://www.catholicnews.com/services/englishnews/2016/in-zika-outbreak-contraceptives-may-be-lesser-evil-pope-says.cfm">Pope Francis</a> hinted at softening the rigid stance of the Catholic Church on contraception because of the threat posed by the Zika virus. But in most Latin American countries affected by Zika, abortion is illegal or can only take place in exceptional situations. In <a href="http://www.telesurtv.net/english/news/El-Salvador-Fights-to-Preserve-Tourism-Amid-Zika-Virus-Outbreak-20160215-0025.html">El Salvador</a>, for instance, where more than 7,000 cases of Zika were reported between December 2015 and January 2016, abortions and miscarriages can even lead to homicide convictions if proven to be self-induced.</p>
<p>Citing principles set out in Brazil’s constitution, advocacy groups there have <a href="https://www.law.yale.edu/yls-today/news/petition-seeks-protect-zika-affected-women-and-families">filed a legal</a> petition to the Supreme Court calling for the protection of sexual and reproductive health rights and social protection for <a href="https://www.youtube.com/watch?v=j9tqt0jaoG0&list=PLf-Oz5dUh_njeIcx-40L99fCs31u7CmeL&index=2">women and families affected by Zika</a>. The <a href="http://anis.org.br/acao-sobre-zika-no-stf-vai-alem-do-aborto/">petition is yet to be heard</a> but if successful should lead to a review of current restrictive abortion laws, legalising abortion in cases where the fetus develops without a major part of its brain and skull. </p>
<p>Yet, this case faces opposition by the conservative and influential “<a href="http://www.reuters.com/article/us-brazil-politics-conservatives-idUSKCN0ZA2RT">bullets, beef and bible</a>” caucus, composed of evangelical Christians, the farm lobby and lawmakers, who support a right-wing social agenda, including tougher abortion restrictions. </p>
<p>In February 2016, the Obama administration asked Congress to sanction $1.8 billion in emergency funding to help prepare for and respond to the threat posed by the Zika virus. But abortion politics <a href="https://theconversation.com/how-congress-is-failing-on-zika-65459">sterilised these discussions</a> as Republican lawmakers leading a congressional hearing on the Zika outbreak made funding conditional on <a href="https://www.statnews.com/2016/02/10/zika-hearing-congress-abortion/">anti-abortion policies</a> in recipient countries. Eventually a $1.1 billion aid package <a href="http://www.npr.org/sections/health-shots/2016/09/28/495806979/congress-ends-spat-over-zika-funding-approves-1-1-billion">was agreed</a> in late September. However, Zika programmes supporting abortions have now been put in financial <a href="http://www.npr.org/sections/health-shots/2016/09/28/495806979/congress-ends-spat-over-zika-funding-approves-1-1-billion">jeopardy</a> following the Trump <a href="https://theconversation.com/trumps-global-gag-rule-will-cause-more-abortions-not-fewer-71881">administration’s order</a> to rule out funding for birth control programmes. </p>
<p>The delivery of health care programmes in Latin America should be anchored in an understanding of the inequalities, discrimination and power relations that prevent many people from accessing them. Governments should remember that they have legal and ethical obligations under international law to ensure the best possible provision of services for all.</p><img src="https://counter.theconversation.com/content/72460/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Pia Riggirozzi received funding from ESRC-DfID grant Poverty Reduction and Regional Integration: SADC and Unasur Health Policies (PRARI)</span></em></p>Zika is not gender neutral: women’s rights are at stake.Pia Riggirozzi, Associate Professor in Global Politics, University of SouthamptonLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/693432016-11-25T01:13:09Z2016-11-25T01:13:09ZZika ‘health emergency’ status removed but it’s sad news for reproductive health<p>The <a href="http://www.abc.net.au/news/2016-11-19/who-declares-end-to-zika-virus-emergency/8039566">recent announcement</a> the World Health Organisation (WHO) has <a href="http://www.who.int/mediacentre/news/statements/2016/zika-fifth-ec/en/">declared</a> Zika no longer a “public health emergency of international concern” is sad news. Rather than signalling a victory over this high profile global health threat, it is more a recognition the virus is <a href="https://blogs.scientificamerican.com/guest-blog/the-microbes-have-won-again/">here to stay</a>. </p>
<p>The announcement downgrades Zika to just another of the chronic, complex public health issues countries have to deal with. However, this one has a clear gender dimension. The losers will be women; poor, marginalised women who already have enormous threats to their reproductive health and the health of their babies.</p>
<p>Zika reached prominence in the past year as a <a href="https://theconversation.com/explainer-where-did-zika-virus-come-from-and-why-is-it-a-problem-in-brazil-53425">rapidly spreading outbreak</a> affecting Brazil and other parts of South America but now with active transmission in <a href="http://www.cdc.gov/zika/geo/active-countries.html">more than 60 countries and territories</a>. The particular features of Zika create a reproductive health nightmare that we now know is unlikely to end.</p>
<h2>Women will be disproportionately affected</h2>
<p>Zika in pregnancy has been linked to <a href="https://theconversation.com/explainer-what-is-microcephaly-and-what-is-its-relationship-to-zika-virus-54049">microcephaly</a> – a condition caused by the virus attacking brain cells and leading to small heads and brain damage in babies. </p>
<p>Zika infection often has no symptoms, so pregnant women may be silently infected, with potentially catastrophic outcomes for their child. Testing for mosquito-borne infections can be complex, making it difficult to be certain of infection on blood test alone. </p>
<p>This leaves pregnant women in an affected area unsure of their infection status and the impact on their baby. The only option is to monitor the baby by ultrasound and provide the choice of termination if the condition is detected early enough. An additional complexity for reproductive health is the fact that Zika has been transmitted <a href="https://theconversation.com/zika-via-sex-and-blood-how-worried-should-we-be-54174">sexually</a>.</p>
<p>Nearly 3000 babies have been born with microcephaly since the outbreak began. Although scientific investigations are still continuing, researchers conclude there is a <a href="http://www.cdc.gov/media/releases/2016/s0413-zika-microcephaly.html">link</a> with Zika infection. Although most microcephaly cases are in Brazil, there have been cases in other countries and the full extent of the problem is far from clear. </p>
<p>As a <a href="https://theconversation.com/zika-and-ebola-had-a-much-worse-effect-on-women-we-need-more-research-to-address-this-in-future-64868">recent article</a> highlighted, the gender dimensions of global health emergencies such as Zika and Ebola have not received enough attention. In both cases women of reproductive age have been particularly vulnerable to the effects of the outbreaks and tend to come from poor, marginalised communities where their access to reproductive health care is already limited. </p>
<p>In Sierra Leone, a country that already had one of the highest rates of maternal death, maternal and newborn deaths <a href="https://www.theguardian.com/world/2015/oct/07/baby-and-maternal-deaths-soar-in-sierra-leone-amid-ebola-fears-researchers">rose by a third</a> in the height of the Ebola outbreak. In Brazil, the areas most affected by Zika were those where women were <a href="https://www.chathamhouse.org/publication/ia/gendered-human-rights-analysis-ebola-and-zika-locating-gender-global-health#https://www.chathamhouse.org/publication/ia/gendered-human-rights-analysis-ebola-and-zika-locating-gender-global-health">least likely to have access to contraception</a> and medical care.</p>
<h2>Implications of the status downgrade</h2>
<p>When downgrading Zika’s emergency status WHO said its response would remain <a href="http://www.abc.net.au/news/2016-11-19/who-declares-end-to-zika-virus-emergency/8039566">robust</a>. However, this downgrade is a move from emergency response to long term development issue.</p>
<p>The decision is based on WHO’s assessment that the situation no longer meets criteria for a <a href="http://www.vox.com/2016/2/1/10871562/zika-health-emergency-who">public health emergency of international concern</a>. A WHO expert committee can declare such a public health emergency under legal structures set up to govern pandemics called the <a href="http://www.who.int/topics/international_health_regulations/en/">International Health Regulations</a>. </p>
<p>There have only been three previous declarations since the regulations began in 2007 (for swine flu, polio and Ebola). A declaration is a political tool that WHO uses to focus attention and expertise on “extraordinary” global health threats and can allow for trade and travel restriction. </p>
<p>The uncertainty around Zika and explosion of microcephaly cases in Brazil triggered the declaration to mobilise increased surveillance and global awareness. In removing the emergency status WHO has accepted this is not an acute situation that can be limited, that Zika is not going away, and that emergency structures are not the most appropriate framework for this now chronic situation. </p>
<p>WHO acknowledged Zika remains a “significant and enduring public health challenge”, one that should not be underestimated.</p>
<h2>Concerned about the announcement</h2>
<p>Public health experts have reacted with concern to the announcement. Global health expert <a href="https://www.law.georgetown.edu/faculty/gostin-lawrence-o.cfm">Lawrence Gostin</a> called the move <a href="https://www.washingtonpost.com/news/to-your-health/wp/2016/11/18/who-no-longer-considers-zika-a-global-health-emergency-2/">“quite worrying”</a> due to the possibility the international response could become “lethargic”. </p>
<p>The high-level attention, associated <a href="https://www.scientificamerican.com/article/congress-approves-1-1-billion-in-zika-funding/">mobilisation of funds</a>, and pressure for vaccine development, risk losing momentum if Zika is no longer seen as a crisis. </p>
<p>In the absence of a vaccine, which could be years away, women in affected areas face a devastating reproductive health crisis. Preventative measures to avoid mosquito bites have been unable to eliminate transmission in other mosquito-borne infections. </p>
<p>The advice to consider delaying pregnancy is not feasible long-term. Potential public health responses – sex education, access to contraception, access to ultrasound and antenatal care, access (and legal frameworks for) safe and accessible abortion – are already lacking or severely compromised in many areas affected. </p>
<p>The recent WHO announcement takes us into a new phase, one that is unknown and complex. Zika is now a reproductive health threat that is here to stay, another shadow of uncertainty hanging over thousands of women worldwide as they go through the vulnerable journey of pregnancy and childbirth.</p><img src="https://counter.theconversation.com/content/69343/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Catherine Bateman Steel receives funding from the National Health and Medical Research Council and the Royal Australasian College of Physicians to do a PhD in gender equity and global health </span></em></p>The World Health Organisation no longer sees Zika as a health emergency. But what does this downgrade mean for the health of mothers and babies?Catherine Bateman Steel, Adjunct Lecturer and PhD student, School of Social Sciences, UNSW SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/684462016-11-08T13:57:24Z2016-11-08T13:57:24ZZika has created a ‘lost generation’ – helping them is not just our duty, but their right<p>I recently sat with a mother and her baby in an intensive care unit in Rio de Janeiro, Brazil. The baby was tiny, with lots of dark hair and a beautiful name. He also had <a href="http://www.cdc.gov/ncbddd/birthdefects/microcephaly.html">microcephaly</a> – and the doctor euphemistically said that his face was disproportionate to his head. </p>
<p>To my untrained eye, his face looked distorted, and I found it extremely upsetting to look at him. His mother was obviously very anxious, and wondering how she was going to cope when they finally went home. She hadn’t known that she’d had <a href="https://www.cdc.gov/zika/">Zika</a> in pregnancy, so the diagnosis came as a shock to her. The father had blood-shot eyes – from fatigue or crying – and wanted to know whether this had happened because the mother had been vaccinated against rubella as a teenager, one of the rumours circulating in Brazil.</p>
<p>A few days later, I visited a hospital clinic in Recife treating babies affected by Zika. Not all the babies had microcephaly – many had normal-sized heads but other severe disabilities. In fact, microcephaly may actually be just the tip of the iceberg in the Zika crisis, and the focus is now shifting to <a href="http://www.who.int/bulletin/volumes/94/6/16-176990/en/">“Congenital Zika Syndrome”</a>, which covers the full range of conditions affecting these babies. </p>
<p>The shocking thing for me was the sheer number of children at the clinic – they were everywhere I looked. The babies were beautifully dressed and obviously well cared for. The mothers were going through the familiar parental activities of giving bottles of milk, rocking babies to sleep, wiping up baby mess and chatting. But still the atmosphere was anxious, and many of the babies were irritable and crying – common features of babies affected by Zika. </p>
<p>I was in Brazil to take part in a <a href="http://www.lshtm.ac.uk/newsevents/news/2016/school_eu_funding_zika_virus.html">research workshop</a>. I learned about plans to develop diagnostic tests for Zika, animal models to help understand how Zika is damaging the developing brain, new methods to control the vectors of Zika, and models to predict the different likely scenarios. </p>
<p>This new science is cutting edge and will help to prevent and control future Zika epidemics. But it may not do so much to help those babies already affected by Zika – <a href="http://apps.who.int/iris/bitstream/10665/250724/1/zikasitrep3Nov16-eng.pdf?ua=1">at least 2,000 so far in Brazil alone</a>. Without support, these babies are likely to grow up with serious and wide-ranging disabilities, which will severely restrict their ability to live normal lives. Public health messages may also not be much help yet. Most focus so far has been on avoiding infection with Zika and delaying pregnancy – difficult for women who are often very poor and not always in control of their fertility. </p>
<h2>A system overwhelmed</h2>
<p>Of course, some groups in Brazil are trying to help the babies affected by Zika and their families, whether through hospitals or non governmental organisations. Babies are getting some physiotherapy and early stimulation, but this is usually patchy and inconsistent. Some parent groups have been set up, including a very <a href="http://www.pbs.org/wgbh/frontline/article/how-brazilians-use-whatsapp-to-connect-on-zika/">active WhatsApp group</a>. But the few initiatives that try to provide holistic care, such as the <a href="http://www.fundacaoaltinoventura.com.br/site/">Altino Ventura Foundation in Recife</a>, are totally overwhelmed and cannot meet the demand. One clinic told me that for every child that they are treating there is another on their waiting list.</p>
<p>I left Brazil feeling that the world is letting down these babies and their families. Perhaps people feel that not much can be done for them as they will never have normal lives. A senior official in Brazil even called them a “lost generation”. I think there is also an emotional reason: just as I found it difficult to look at the baby in intensive care, we don’t want to confront the reality of these babies and their families. It is too distressing so we look away. </p>
<p>The premise that nothing can be done is also false. Early intervention and stimulation will help these babies to <a href="http://bit.ly/2fjQCEm">have the fullest possible lives</a>. Providing emotional and practical support to the families will also help them to cope better – which is particularly important as I was told time and time again that these mothers are among the poorest of the poor. Zika, after all, is a disease of the most disadvantaged. </p>
<p>Helping these families is not just our duty – it is also their right.</p><img src="https://counter.theconversation.com/content/68446/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Hannah Kuper receives funding from Wellcome Trust to investigate the Social and Economic Impact of Congenital Zika Syndrome. </span></em></p>A moving dispatch from the frontline in the fight against Zika.Hannah Kuper, Reader of Epidemiology, Co-director of International Centre for Evidence in Disability, London School of Hygiene & Tropical MedicineLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/648682016-10-19T19:10:27Z2016-10-19T19:10:27ZZika and Ebola had a much worse effect on women: we need more research to address this in future<figure><img src="https://images.theconversation.com/files/140679/original/image-20161006-20110-s4c85k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Pregnant women in Sierra Leone, Guinea and Liberia were faced with the double fear of dying from Ebola as well during childbirth. </span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/unmeer/16075719060/in/photolist-quygd1-qTRgVy-rdJgMa-q2bC8E-qjrA94-qBtyYD-qgVJhF-rghj2V-rbqLBd-rdznSk-pX9qSP-qjeqm3-rdCnRU-qYMv2i-qW9x4u-qNwU29-rbr83o-pV9LQX-oPRK3S-rgd93e-qMihHA-qBtwhM-qRVMVR-dtTWk9-qBtucz-qBtzcV-rg9v2d-rdznhH-oEq7Yu-oH6sAV-qzmww9-rdUTtm-rbqKZb-qgVFMv-pudFgi-pX9r6p-qRCJCd-pWVAtQ-rghiXg-qBmjFo-qBv2w4-pX9q9e-rghiKn-oTDnsX-qWifKt-qjvJUH-rgb17K-rdUUDh-piAso6-GFGPP3">UNMEER/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>Outbreaks of the Ebola virus – declared as a public health emergency in 2015 – and, more recently, Zika, had a disproportionate impact on women. In issuing emergency advice, international agencies acknowledged the different experiences of men and women during both crises. </p>
<p>But as we found in our recently published article in <a href="https://www.chathamhouse.org/publication/ia/gendered-human-rights-analysis-ebola-and-zika-locating-gender-global-health#https://www.chathamhouse.org/publication/ia/gendered-human-rights-analysis-ebola-and-zika-locating-gender-global-health">International Affairs</a>, the advice they offered did not take into account women’s limited capacity to protect themselves from infection.</p>
<p>We found less than 1% of published research papers around the time of both outbreaks, and that related to the outbreaks, actually explored their gendered impact. Research that examines the gendered inequality of public health emergencies must be conducted to inform future international responses.</p>
<h2>Exacerbating existing inequality</h2>
<p>By the end of 2015, the three West African countries most affected by Ebola – Guinea, Liberia and Sierra Leone - <a href="http://apps.who.int/ebola/current-situation/ebola-situation-43-report-4-November-2015">had a total of 8,703 cases of the virus</a> in women compared to 8,333 in men. But the sex tally of those infected does not reveal the <a href="http://www.undp.org/content/dam/undp/library/crisis%20prevention/Recovering%20from%20the%20Ebola%20Crisis-Full-Report-Final_Eng-web-version.pdf">social impact</a> of the disease on local populations.</p>
<p>In October 2014, it was estimated more than 600,000 <a href="http://www.rhm-elsevier.com/article/S0968-8080(14)44820-1/abstract">women would be giving birth</a> in Liberia, Guinea and Sierra Leone over the next 12 months. In these countries, where maternal death rates are usually high, pregnant women <a href="http://www.rhm-elsevier.com/article/S0968-8080(14)44820-1/abstract">were said to now be facing</a> “the double fear of dying from Ebola and during childbirth”. </p>
<p>In addition, estimates published in the Lancet medical journal showed an extra 4,022 women <a href="http://www.thelancet.com/journals/langlo/article/PIIS2214-109X(15)00065-0/fulltext">would die annually in childbirth</a> in the three affected countries as a result of a shortage of health care workers who had died from the virus. </p>
<p>Although the outbreak is over, women <a href="http://thelancet.com/journals/langlo/article/PIIS2214-109X(16)30175-9/fulltext">continue to be at risk</a> of contracting the disease from unprotected sexual intercourse with men who were previously infected by Ebola.</p>
<p>Given Zika’s <a href="https://theconversation.com/explainer-what-is-microcephaly-and-what-is-its-relationship-to-zika-virus-54049">link to microcephaly</a> – a condition where babies of infected women are born with small heads – the outbreak more obviously affected pregnant women than did Ebola.</p>
<p>During the outbreak’s initial phase, there was open discussion about the links between the geographical location of microcephaly cases and the women most affected. These women were more likely to be Indigenous and come from either <a href="https://www.washingtonpost.com/news/world/wp/2016/02/24/zika-exposes-class-differences-in-brazil-where-most-victims-are-poor/">urban poor or remote locations</a>, as well as lack access to contraceptives and abortion.</p>
<p>The irony <a href="http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(16)00331-7/abstract">was noted</a>: already marginalised women were being asked by governments to avoid pregnancy. This was <a href="http://www.bbc.com/news/world-latin-america-35388842">without acknowledgement by these same governments</a> of their own role in hindering women’s access to contraceptives, sex education and safe abortion practices in the first place.</p>
<h2>Our study</h2>
<p>In the case of both outbreaks, we were concerned about the lack of international bodies’ early discussion on how to support women to take preventive measures again the diseases. We wondered if lessons had been learnt from the Ebola outbreak to enable a different gender experience during the Zika outbreak.</p>
<p>To answer our question, we searched articles published in the Scopus journal database (covering 29 million abstracts in over 15,000 peer-reviewed titles from more than 4,000 publishers) for Zika– and Ebola–related pieces.</p>
<p>Between 1 January 2015 and 15 May 2016, just 21 articles of 608 publications explored the relationship between “Zika” and “human rights”. Two articles explored “human rights”, “gender” and “Zika infection”. But only one article talked about women’s risk of Zika infection due to gender inequality.</p>
<p>In the case of the Ebola outbreak in West Africa, using a date range from 1 January 2014 to 15 May 2016, we searched “Ebola” and “human rights”; “Ebola” and “gender”; “Ebola” and “human rights” and “gender”. </p>
<p>Of 4,236 articles published on Ebola in Scopus during this period, 335 examined Ebola and human rights; 14 examined gender relations in the context of the Ebola outbreak; and one examined the relationship between human rights, gender relations and the outbreak. </p>
<h2>Why is this important?</h2>
<p>The social and economic conditions affecting women’s options and ability to control their risk of infection has received comparatively little attention to that of the overall consequences of both outbreaks. </p>
<p>Even if women adequately protect themselves from infection and survive Zika and Ebola, they are still unlikely to have improved equitable health opportunities after these emergencies. Indeed, they face the risk of worse health and inequality.</p>
<p>More research examining the effect of gendered inequality of public health emergencies must be conducted to inform future international advice and responses, so those affected can survive the crisis without compounding existing inequalities.</p><img src="https://counter.theconversation.com/content/64868/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Sara Davies receives funding from Australian Research Council.</span></em></p><p class="fine-print"><em><span>Belinda Bennett 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>We found that less than 1% of published research papers around the time of both outbreaks, that related to the outbreaks, actually explored their gendered impact.Sara Davies, ARC Future Fellow, Griffith UniversityBelinda Bennett, Professor of Health Law in the Australian Centre for Health Law Research, Queensland University of TechnologyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/624632016-08-05T15:28:17Z2016-08-05T15:28:17ZI’m an OB-GYN treating women with Zika: This is what it’s like<figure><img src="https://images.theconversation.com/files/133175/original/image-20160804-513-11plkej.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Talking with patients who've had Zika is tough.</span> <span class="attribution"><a class="source" href="http://www.shutterstock.com/pic-159741362/stock-photo-the-pregnant-woman-who-has-an-examination.html?src=YPd0wl-YeKuWW_3sd1XLZQ-5-37">Pregnant woman and doctor image via www.shutterstock.com.</a></span></figcaption></figure><p>As a medical student, I remember reading books about the early days of the HIV epidemic and wondering what it was like for doctors to take care of patients who had a new, unknown disease. It seemed to me like it would be frightening for both patients and doctors alike. I didn’t expect that early in my career as an OB-GYN, I would be caught in the middle of another new disease outbreak – Zika.</p>
<p>Most people who catch this virus feel fine. Some will end up with a fever, rash, aches and pains and red eyes (conjuntivitis), or rarely, a serious nerve disorder called <a href="http://www.cdc.gov/zika/about/gbs-qa.html">Guillain-Barre</a>. But in pregnancy there can be very serious consequences to the baby. As of July 28, the World Health Organization reports that nearly <a href="http://apps.who.int/iris/bitstream/10665/246261/1/zikasitrep28Jul2016-eng.pdf?ua=1">2,000 babies are affected</a> with <a href="http://www.cdc.gov/ncbddd/birthdefects/microcephaly.html">microcephaly</a> or central nervous system malformations associated with Zika worldwide.</p>
<p>I teach and practice obstetrics and gynecology at the University of Miami Hospital and Jackson Memorial Hospital, and I treat pregnant women who have been infected with Zika: so far over a dozen women. We began preparing to care for infected women in January. Now, it is part of the daily care we provide. And with first known cases of local mosquito-borne transmission <a href="http://www.nytimes.com/2016/07/30/health/zika-virus-florida-case.html">in the continental U.S.</a> reported in Wynwood, a neighborhood in Miami, the risk has become even more real.</p>
<p>How am I, and other doctors who care for pregnant women, dealing with this new disease? </p>
<h2>Confirming the diagnosis</h2>
<p>When I talk to patients these days, I ask them where they or family members have traveled recently. These are questions OB-GYNs across the country <a href="http://www.cdc.gov/mmwr/volumes/65/wr/mm6529e1.htm?s_cid=mm6529e1_e">may ask pregnant patients</a>. And since I practice in Miami, I might also ask patients if they have been in Wynwood, the neighborhood where local mosquito transmission has occurred. Since Zika is primarily spread by mosquitoes, I also talk with patients about avoiding mosquito bites and using bug repellent. Sexual transmission is also possible, and we talk about that, too.</p>
<p>The patients I worry about the most now are those who live or work in Wynwood and those who’ve traveled to countries where Zika is more widespread, or those who show the symptoms of Zika infection. We are being vigilant for evidence of spread to other parts of the Miami area.</p>
<p>If I am worried that a pregnant patient has been infected with Zika, I order tests to confirm the diagnosis. The state of Florida has announced that starting next week there will be free Zika testing for all pregnant women through the Department of Health. </p>
<p>If a Zika infection is confirmed, we then have to talk about the risks that she is willing to accept in her pregnancy. If a patient infected with Zika is in her first or second trimester, then we can talk about staying pregnant or having an abortion.</p>
<p>While we think that the first trimester is the time of greatest risk, we still don’t know if there is ever a safe point in pregnancy. So how much risk is she willing to accept? What would it mean to have a sick baby in her family? How would she get support no matter what options she chooses? Those answers will be different for everyone.</p>
<p>And these conversations are difficult, because there is still so much we don’t know about Zika.</p>
<p>For instance, we don’t know how many pregnant women who are infected with Zika will have babies with brain problems - there is no perfect percentage I can give her so she can weigh her options. </p>
<p>One study from Brazil found that of the women who were pregnant, had symptoms of Zika and had blood tests confirming infection, a startling <a href="http://dx.doi.org/10.1056/NEJMoa1602412">29 percent of the pregnancies</a> had some sort of issue, such as microcephaly or abnormal brain structure, for instance. But other computer modeling studies have put the risk for the general population of pregnant women who are infected in the first trimester at about <a href="http://dx.doi.org/10.1016/S0140-6736(16)00651-6">1 percent</a>. It’s these wide ranges in outcomes that makes counseling patients so difficult.</p>
<p>And that’s not the only unknown about Zika. </p>
<p>How does the virus get into the fetus? Researchers <a href="http://dx.doi.org/10.1016/j.chom.2016.07.002">are still figuring that out</a>. In which trimester does infection pose the highest risk? As with other infections in pregnancy, it seems that the <a href="http://dx.doi.org/10.1016/j.epidem.2016.03.001">first trimester is the most at risk</a>, but there are still plenty of unknowns. And do complications for the fetus vary by time of infection? It is going to take time to understand all of the risks.</p>
<p>To answer these questions, countries are creating registries of pregnant women with Zika to gather data about what happens to their pregnancies and the babies after birth. Departments of health in each state keep anonymized data on all pregnant women with Zika. This data gets fed into the CDC’s surveillance system, <a href="http://www.cdc.gov/zika/hc-providers/registry.html">the U.S. Zika Pregnancy Registry</a>.</p>
<p>As of July 28, the CDC was monitoring over <a href="http://www.cdc.gov/zika/geo/pregwomen-uscases.html">900 pregnant women</a> in the United States and U.S. territories with laboratory evidence of Zika infection based on blood testing. Researchers want to know if these babies have the same mental development and meet the same milestones as other infants, or if they have eye or ear problems that cannot be seen on ultrasound or immediately after birth. The CDC also reports <a href="http://www.cdc.gov/zika/geo/pregnancy-outcomes.html">15 babies with birth defects</a> from pregnancies with laboratory evidence of Zika infection and six pregnancy losses in the United States and District of Columbia, as of July 28.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/133168/original/image-20160804-481-vi82qo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/133168/original/image-20160804-481-vi82qo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=385&fit=crop&dpr=1 600w, https://images.theconversation.com/files/133168/original/image-20160804-481-vi82qo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=385&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/133168/original/image-20160804-481-vi82qo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=385&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/133168/original/image-20160804-481-vi82qo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=483&fit=crop&dpr=1 754w, https://images.theconversation.com/files/133168/original/image-20160804-481-vi82qo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=483&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/133168/original/image-20160804-481-vi82qo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=483&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">Ultrasounds are helpful, but can’t detect everything.</span>
<span class="attribution"><a class="source" href="http://www.shutterstock.com/pic-395886538/stock-photo-medical-images-collage-of-ultrasound-during-woman-pregnancy-showing-fetus-in-third-month.html?src=OSK7IPwaaTzXRkJ2QprP6w-1-6">Ultrasound image via www.shutterstock.com.</a></span>
</figcaption>
</figure>
<h2>Planning for birth</h2>
<p>If a woman is in her third trimester and has been infected with Zika, at each visit we focus on planning for birth, monitoring the baby by ultrasound and reviewing the latest research together. </p>
<p>Since this is such a fast-moving and public epidemic, we are sharing the research with our patients to keep them involved and help them understand why it is so important to collect as much information as possible. </p>
<p>We might also plan for monthly ultrasounds. It is possible that a baby that looks normal on one ultrasound may show problems on a later ultrasound. Some problems can develop over time and become obvious later. However, ultrasounds can’t detect every problem, and microcephaly isn’t the only problem Zika can cause. So, we plan her delivery at a hospital with pediatricians who know about Zika and can be prepared to care for the newborn, and look at the baby’s eyes and ears and in some cases do brain imaging tests after birth. </p>
<p>Even with planning, there are still many questions we can’t answer for our patients. For instance, if a baby is born with microcephaly, we don’t know the exact issues that the baby might have. This means the mother won’t know right away if her child will lead a normal life or will always need medical care. </p>
<h2>A dose of humility</h2>
<p>Physicians like me are learning about Zika along with our patients. This takes a dose of humility on our part and an understanding from our patients that we learn something new every single day. </p>
<p>With daily news and internet updates, patients are able to stay just as up-to-date as the doctors. I will have patients print out a news article or a research finding and bring it to their appointment, highlighted and with questions in the margins.</p>
<p>But this barrage of media can also lead to confusion and concern when the information is constantly changing. For this reason, it is so important to have open lines of communication with our patients, and be honest about the uncertainties.</p><img src="https://counter.theconversation.com/content/62463/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Christine Curry 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>Physicians like me are learning about Zika along with our patients. This takes a dose of humility on our part and an understanding from our patients that we learn something new every single day.Christine Curry, Assistant Professor of Obstetrics and Gynecology, University of MiamiLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/617762016-08-01T03:07:18Z2016-08-01T03:07:18ZIn Zika, echoes of US rubella outbreak of 1964-65<figure><img src="https://images.theconversation.com/files/132268/original/image-20160727-21564-16ebip6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A display used to educate the public on rubella vaccination and the mother-to-fetus transmission of this virus.</span> <span class="attribution"><a class="source" href="https://phil.cdc.gov/phil/details.asp">Centers for Disease Control and Prevention via Public Health Image Library</a></span></figcaption></figure><p>Just over 50 years ago, a highly contagious but seemingly harmless virus swept through the United States, infecting as many as <a href="http://www.cdc.gov/vaccines/pubs/pinkbook/rubella.html#congenital">12.5 million people</a>. In both adults and children, the virus presented as a mild illness, but caused birth defects in some babies born to women who were infected while pregnant.</p>
<p>Does this sound familiar? Though separated by time and place, there are surprising similarities in the social issues raised by the rubella outbreak of 1964-65 and the recent Zika outbreak in South America. </p>
<p>Both viruses can cause birth defects, a fact that ties them to social issues surrounding pregnancy, women’s health and the politics of abortion. </p>
<p>The rubella epidemic, with an estimated <a href="http://aje.oxfordjournals.org/content/92/3/162.full.pdf+html">20,000 affected newborns</a>, changed medical and public consciousness about the virus. Some have recently argued that it even <a href="http://news.nationalgeographic.com/2016/02/160205-zika-virus-rubella-abortion-brazil-birth-control-womens-health-history/">changed ideas about abortion</a>. </p>
<p>As a sociologist who studies medicine and science, I am interested in understanding the narratives we develop about disease. I examined the rubella outbreak in my 2008 book, <a href="https://books.google.ca/books/about/The_Vaccine_Narrative.html?id=9fqdGAAACAAJ&redir_esc=y&hl=en">“The Vaccine Narrative,”</a> and how perceptions of the disease interacted with stories about vaccination. </p>
<p>Unlike other vaccines, the rubella vaccine conferred no direct benefits to recipients. Instead, it promised to prevent possible future birth defects and to reduce rubella-related abortions; for rubella vaccine, the health of the woman mattered almost entirely in terms of her status as a potential mother.</p>
<h2>The rubella outbreak of 1964-65 – and access to abortion</h2>
<p>In the spring of 1964, doctors in North America confirmed that the <a href="http://www.cdc.gov/vaccines/pubs/surv-manual/chpt15-crs.html">deafness and blinding cataracts</a> they found in massive numbers of children had been caused by rubella. </p>
<p>Before the this outbreak, rubella was obscure, but not unknown. Unlike Zika, which is primarily transmitted by mosquitoes, rubella can spread through casual contact. In fact it was was endemic in Western populations, with <a href="http://archpedi.jamanetwork.com/article.aspx?articleid=503198">more than 80 percent of the population exposed to the disease</a> before rubella vaccination was introduced in 1969. </p>
<p>Health professionals had known <a href="https://books.google.ca/books?id=yiUrAAAAYAAJ&pg=RA1-PA168&lpg=RA1-PA168&dq=Congenital+Defects+in+Infants+Following+Infectious+Diseases+during+Pregnancy&source=bl&ots=3AddxjRWU4&sig=Lba4ti_sazcTTTibpZdBfWnIL18&hl=en&sa=X&ved=0ahUKEwiUq6qrp_jNAhXMHx4KHfUSCuIQ6AEINzAE#v=onepage&q&f=false">since 1943</a> that rubella sometimes caused birth defects, called Congenital Rubella Syndrome (CRS). In another parallel with Zika, people infected with rubella are often asymptomatic. Even when people do have symptoms, they are fairly mild.</p>
<p>Researchers isolated the rubella virus <a href="http://archpedi.jamanetwork.com/article.aspx?articleid=503144">only in 1962</a>, and there was <a href="http://query.nytimes.com/gst/abstract.html?res=9E06E1DF1F30E033A25752C2A9629C946491D6CF&legacy=true">no blood test until 1965</a>. </p>
<p>Before the blood test was available, a doctor’s clinical diagnosis of rubella could access a <a href="http://scholarlycommons.law.case.edu/cgi/viewcontent.cgi?article=4360&context=caselrev">medical exception</a> to the ban on abortions that existed in most states, called a “therapeutic abortion.” This exception considered the physical and mental health of the woman as medically relevant for whether an abortion could happen. Decisions about rubella-related abortion happened in the context of the doctor-patient relationship.</p>
<p>Because rubella was so common, and because an infected person could be asymptomatic, some physicians had argued as early as the 1950s that <a href="http://scholarworks.umb.edu/cgi/viewcontent.cgi?article=1205&context=nejpp">rubella served as a convenient way to circumvent the laws restricting abortion</a>. </p>
<p>In fact, prior to Roe v. Wade in 1973, a rubella diagnosis was <a href="http://scholarlycommons.law.case.edu/cgi/viewcontent.cgi?article=4360&context=caselrev">one of the main ways</a> for women to obtain safe abortions, performed by qualified doctors, without either physician or patient subject to prosecution. </p>
<p>Even when abortion was illegal throughout the U.S., the law recognized the primacy of the doctor-patient relationship, deferring to <a href="https://books.google.ca/books?id=FK4pBXGvQzoC&printsec=frontcover&source=gbs_ge_summary_r&cad=0#v=onepage&q&f=false">the authority of American medicine</a> and the privacy of women’s medical decisions. Roe v. Wade, which legalized abortion in the U.S., is built on the right to privacy.</p>
<h2>The development of the vaccine</h2>
<p>In the aftermath of the 1964-65 epidemic, epidemiologists predicted that another rubella epidemic – along with thousands of babies born deaf or blind – would begin in 1970. This spurred the effort to develop a rubella vaccine to prevent birth defects. However, another goal was to reduce what vaccine researchers at the time often referred to as “fetal wastage,” a euphemism for abortion. In fact, many in the medical profession at that time appeared to view women’s health as secondary to the importance of pregnancies brought to term with healthy babies and avoiding “<a href="http://scholarworks.umb.edu/cgi/viewcontent.cgi?article=1205&context=nejpp">unnecessary abortions</a>.”</p>
<p>A preventive vaccine became available in 1969, and versions are currently in wide use; it is the “R” in the trivalent childhood MMR vaccine. Today, the Centers for Disease Control and Prevention reports that rubella, once endemic, has been <a href="http://www.cdc.gov/vaccines/pubs/surv-manual/chpt15-crs.html">all but eliminated in the U.S.</a>, and rubella-related birth defects with it.</p>
<p>In 1970 when the predicted epidemic failed to materialize, credit went to mass vaccination <a href="http://www.nejm.org/doi/full/10.1056/NEJM197602052940604">(despite some uncertainties, as the population had already been largely immune)</a>. This meant that the underlying social issues that rubella had raised – the role of medicine in regulating access to abortion; whether the physical and mental effects of birth defects <em>on women</em> justified an abortion – would be deferred. </p>
<p>Still, the realization that birth defects were an important consideration in the politics of abortion <a href="http://digitalcommons.law.yale.edu/cgi/viewcontent.cgi?article=2089&context=fss_papers">made therapeutic abortion more available</a> between 1965 and the 1973 Roe v. Wade decision, as blood tests replaced clinical diagnoses, though the rate of rubella-related birth defects remained unknown. </p>
<h2>Parallels with Zika</h2>
<p>The rubella outbreak happened in a context where abortion was illegal – save for medical exceptions. In much of South America, where Zika’s effect has been greatest, access to <a href="https://theconversation.com/zika-and-abortion-will-the-virus-prompt-latin-america-to-rethink-abortion-and-birth-control-55200">safe abortion is severely restricted</a>. </p>
<p>As Zika has spread in Latin America, researchers have found that <a href="http://news.utexas.edu/2016/06/22/abortion-demand-increases-with-zika-virus-advisories">abortion requests have increased</a>, setting the stage for a replay of the history of rubella. As with rubella, in areas where Zika has become prevalent and abortion is almost always illegal, <a href="https://www.theguardian.com/global-development/2016/jul/19/zika-emergency-pushes-women-to-challenge-brazil-abortion-law">women have begun to demand access to therapeutic abortions</a>. </p>
<p>Perhaps, therefore, medical and public health measures will stop Zika, as they did rubella for North Americans. </p>
<p>But developing a vaccine for Zika or halting its spread will not address the social issues that the virus has raised: women’s right to control their own bodies, concerns about “fetal wastage” and the relative importance of healthy, live births versus women’s mental and physical health.</p><img src="https://counter.theconversation.com/content/61776/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jacob Heller 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>Though separated by time and place, there are surprising similarities in the the social issues raised by the rubella outbreak of 1964-65 and the recent Zika outbreak in South America.Jacob Heller, Associate Professor, SUNY Old WestburyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/628222016-07-25T21:04:14Z2016-07-25T21:04:14ZThe Olympics won’t spread Zika around the world<p>The opening ceremonies of the 2016 Olympics in Rio de Janeiro are just days away. But this year, fears of Zika have cast a shadow over festivities.</p>
<p>The Zika virus is the cause of an ongoing epidemic of birth defects first noticed in Brazil <a href="https://theconversation.com/explainer-where-did-zika-virus-come-from-and-why-is-it-a-problem-in-brazil-53425">in late 2015</a>. While the virus causes no symptoms in most people, infections of pregnant women can lead to <a href="http://www.cdc.gov/ncbddd/birthdefects/microcephaly.html">microcephaly</a>, blindness, spontaneous abortion or stillbirth of the fetus. Now affecting nearly all Latin American and Caribbean countries, the Zika outbreak has been declared a <a href="http://www.who.int/mediacentre/news/statements/2016/emergency-committee-zika-microcephaly/en/">public health emergency of international concern</a> by the World Health Organization (WHO).</p>
<p>As scientists and health agencies race to keep up with the epidemic, it’s no surprise that the threat of Zika during the Olympics has been in the news. </p>
<p>Over 200 international academics, led by Canadian law and medicine professor <a href="https://twitter.com/profamirattaran">Amir Attaran</a>, brought considerable attention to the issue in May, signing an open <a href="https://www.washingtonpost.com/news/to-your-health/wp-content/uploads/sites/26/2016/05/Zika-Olympics-Open-Letter-to-WHO-current2.pdf?tid=a_inl">letter</a> advocating that the Olympics should be postponed or relocated so that visitors do not import Zika virus to their home countries.</p>
<p>For its part, the WHO has maintained that canceling the Olympics or changing the location of the games <a href="http://www.who.int/mediacentre/news/releases/2016/zika-health-advice-olympics/en/">will not lessen the risk</a> of Zika spreading internationally. Meanwhile, the U.S. Centers for Disease Control and Prevention has pointed out that the Olympics will account for <a href="http://www.cdc.gov/mmwr/volumes/65/wr/mm6528e1.htm">less than 0.25 percent of all travel to Zika-affected countries</a> this year. Regular travel between the U.S., the Caribbean and Latin America has led to over <a href="https://www.cdc.gov/zika/geo/united-states.html">1,400 imported disease cases</a> within U.S. states this year. However, local mosquito-borne transmission has not yet been reported within the 50 states, and only 15 cases of domestic sexually transmitted cases are known to have occurred.</p>
<p>These assurances have done little, however, to relieve public perceptions of risk in a news cycle dominated by announcements that <a href="http://qz.com/682002/these-athletes-are-skipping-the-olympics-because-of-zika/">some athletes</a> will skip the Olympics over Zika fears.</p>
<p>As academic scientists working at the intersection of public health, medicine, operations research and human rights, my colleagues and I have been dismayed watching how this controversy played out over the airwaves. Policymakers and travelers need evidence to make sound decisions. Questions over Zika risk at the Olympics must be addressed scientifically.</p>
<p>To bring evidence into the Zika debate, we calculated how big a risk the virus poses for travelers visiting Rio for the Olympics as well as for the countries into which these individuals may import the virus. Our <a href="http://annals.org/article.aspx?articleid=2538663">findings were published today</a> in the Annals of Internal Medicine.</p>
<h2>How do the numbers play out?</h2>
<p>The state of Rio de Janeiro, Brazil saw <a href="http://combateaedes.saude.gov.br/images/sala-de-situacao/Microcefalia-Protocolo-de-vigilancia-e-resposta-10mar2016-18h.pdf">between 15,918 and 143,985</a> Zika virus infections in the year 2015, in a population of 16.5 million. The precise number of infections is uncertain because most people who get infected never show symptoms. Even among those who do, the rash, fever, headache or joint pain that typically occur may not be severe enough to warrant a visit to the clinic, meaning many cases won’t appear in health statistics.</p>
<p>August is winter in the Southern Hemisphere. While mosquitoes can still be active this time of year, their ability to transmit infections is weak. This is one of the reasons that dengue, which is also spread by the <em>Aedes aegypti</em> mosquito, mostly affects Rio <a href="http://portalsaude.saude.gov.br/images/pdf/2016/janeiro/07/2015-svs-be-pncd-se48.pdf">between March and June</a>, when temperatures are higher and rain is more frequent. Having seen many seasons of dengue transmission, we’d expect the risk of acquiring Zika from a mosquito to go down about 60 percent in August relative to the annual average.</p>
<p>Accounting for these factors, we estimate that between 6 and 80 infections will occur among the 350,000 to 500,000 athletes, delegates, spectators and vendors descending on Rio for the Olympics. Since only one to 16 of these individuals would be expected to show symptoms, we are unlikely to hear about many reported Zika cases among travelers.</p>
<h2>What about the risk to other countries?</h2>
<p>Because most people clear Zika virus from their blood <a href="http://www.who.int/bulletin/online_first/16-174540.pdf">in less than 10 days</a>, many travelers who become infected in Brazil are likely to be free of the virus before or shortly after returning home. Accounting for this rate of clearing the virus, we anticipate only 3 to 37 travelers – roughly half those who become infected in Brazil – importing Zika virus to their home countries.</p>
<p>Based on the <a href="http://www.turismo.gov.br/images/pdf/anuario_estatistico_de_turismo_2015_ano_base_2014_pdf.pdf">breakdown of travelers</a> who visited Brazil for the 2014 FIFA World Cup, over half the visitors will likely return to U.S. states, Canada, Oceania and temperate European and Asian countries, where the risk of local mosquito-borne transmission is low. A further 30 percent of travelers will be going back to Latin American countries where transmission is already established.</p>
<p>This leaves under 20 percent of the 3 to 37 infected travelers at risk of introducing Zika to African, Asian and Middle East countries where we worry about the virus taking hold. In fact, the projected delegation of athletes and travelers from Chad, Djibouti, Eritrea and Yemen – the only four countries where the CDC projects the Olympics <a href="http://www.cdc.gov/mmwr/volumes/65/wr/mm6528e1.htm">pose a unique threat</a> of Zika introduction – amounts to 76 travelers.</p>
<h2>Reality check</h2>
<p>Based on our calculations, a visitor’s chance of becoming infected with Zika at the Olympics and then importing the virus to his or her home country is low. Our outcomes support the position of the WHO that canceling the Olympics, or relocating the games, is not going to alter the international spread of Zika. In a world connected by travel and migration, opportunities for the virus to cross borders extend far beyond sporting events.</p>
<p>The controversy over the Olympics should not distract us from the global threat Zika poses. But we should keep fears about the Olympics in perspective. </p>
<p>The domestic chaos over Ebola in 2014 is all it takes to remind us what happens when our reactions are guided by fear, rather than by evidence.</p>
<p>As West Africa reeled under its epidemic, U.S. governors forcibly quarantined travelers from West Africa – even those <a href="http://www.nytimes.com/2015/12/03/health/ebola-crisis-passes-but-questions-on-quarantines-persist.html">who had not been exposed to Ebola cases</a> – against the advice of public health experts. Students and teachers were <a href="http://www.huffingtonpost.com/2014/10/23/africa-ebola_n_6031204.html">barred from entering schools</a> after traveling to countries like South Africa and Kenya, thousands of miles from the epidemic. At best, these reactionary responses to epidemics are costly and <a href="http://www.nejm.org/doi/full/10.1056/NEJMe1413139#t=article">counterproductive</a>. At worst, they <a href="http://www.nejm.org/doi/full/10.1056/NEJMp1413425">stigmatize affected countries and their populations</a>.</p><img src="https://counter.theconversation.com/content/62822/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Joseph Lewnard 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 chance the someone at the Rio games will import the virus to their home country is low.Joseph Lewnard, PhD candidate, Yale UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/618102016-07-07T02:26:34Z2016-07-07T02:26:34ZNews of Zika vaccine might be reassuring, but it’s too late for Rio, and do we really need it anyway?<p>Recently, two events concerning the Zika epidemic coincided: two potential vaccines against the virus were <a href="http://www.nature.com/nature/journal/vaap/ncurrent/full/nature18952.html#main">declared a success</a> when used in mice, and Australian golfer <a href="http://www.abc.net.au/news/2016-06-29/jason-day-hopes-golf-stays-in-the-olympics-despite-rio-withdraw/7552788">Jason Day withdrew</a> from the Olympic Games, purportedly because of his concern about the possibility of getting infected. </p>
<p>The number of media reports of these events highlight the sensationalism around Zika and the challenges faced by scientists and public health professionals in translating science to policy.</p>
<p>Zika captured global public attention partly through the spectacle of the birth deformities it has been linked to, particularly <a href="https://theconversation.com/explainer-what-is-microcephaly-and-what-is-its-relationship-to-zika-virus-54049">microcephaly</a> and <a href="https://theconversation.com/explainer-what-is-guillain-barre-syndrome-and-is-it-caused-by-the-zika-virus-53884">other neurological disorders</a>, but partly also because of the Olympic Games. Without the economics of international sport, the virus may well have been ignored.</p>
<p>Zika was first identified in humans in Uganda some 70 years ago. By early July 2016, the current epidemic was prevalent throughout the Americas and in Asia and the Western Pacific region.</p>
<p>It is a comparatively benign virus: many people do not know they are infected, in contrast with other viruses in the same family (flaviviruses). Yellow fever is now largely controlled through vaccination and medical surveillance. Dengue fever and dengue haemorrhagic fever, and chikungyna are virulent, but are considered neglected diseases of poverty. </p>
<p>The diseases affect poor people in poor countries with limited capacity to manage the environment, control the carrier, or provide accessible and affordable health care.</p>
<p>Zika virus infection was <a href="https://theconversation.com/zika-emergency-status-a-cause-for-alert-not-alarm-54042">declared a public health emergency</a> of international concern in February 2016. This followed an increase in infections in Brazil and its suspected link with congenital anomalies. The number of people who have contracted the Zika virus is imprecise – in part because those who are infected may have no obvious signs, compared with the more deadly flaviviruses – dengue fever, chikungunya and yellow fever. </p>
<p>All are transmitted by the mosquito species <em>Aedes aegypti</em> and <em>Aedes albopictus</em>. The prevalence of these species varies with topography, precipitation, population density, the management of hard waste, and the built environment.</p>
<h2>What do we know about the vaccine so far?</h2>
<p>The <a href="http://www.nature.com/nature/journal/vaap/ncurrent/full/nature18952.html#main">success of two novel vaccines</a> against Zika in mice is a remarkable achievement, especially given the lack of vaccines against dengue and chikungunya. But the roll-out of either of these vaccines is too far off to impact the Olympic Games. </p>
<p>We know nothing of the efficacy of the vaccines in the short or long term; their effect on people who have already been infected or are subsequently exposed to other flaviviruses; or their effect on women in pregnancy. Is the vaccine stable in varying temperatures? How resistant is the vaccine to mutation of the virus? How long before the vaccine ceases to be effective?</p>
<p>The next step for the vaccines is to conduct clinical trials in humans. These are usually conducted among poor populations in poor countries not only because of the greater prevalence of the targeted infection, but also because it can be easier to get past their ethics committees to conduct the studies.</p>
<p>Assuming the vaccine is successful, then globally and at country levels we will need to address health systems and service problems. </p>
<p>Who should receive the vaccine, and at what cost? If it is not free, then the vaccine will likely only protect people who are at low risk (tourists, for instance). If it is provided free to poor countries where health systems are weak, then who will cover the high cost of the vaccine roll-out, procurement, storage, local distribution, community education and monitoring across populations?</p>
<h2>So what about Rio?</h2>
<p>While Zika has been reported in around 60 countries, almost all of the <a href="http://www.who.int/emergencies/zika-virus/situation-report/23-june-2016/en/">1,655 cases of microcephaly confirmed by WHO</a> (as at June 22) have occurred in Brazil. The vast majority of these have been in the impoverished states of Pernambuco and Paraiba, over 1,600 kilometres northeast of Rio.</p>
<p>The concentration of cases in this region, predating the rise in the transmission of Zika, has yet to be explained. And only a small proportion of these cases of microcephaly <a href="http://www.paho.org/hq/index.php?_option=com_content&view=article&id=11599:regional-zika-epidemiological-update-americas&Itemid=41691&lang=en">have been shown to be linked to Zika</a>.</p>
<p>The mosquito carrier, or “vector”, is active in Rio de Janeiro, but biting rates are low in August – the month of the Olympics. This means the risk of any disease transmitted by <em>Aedes</em> mosquitoes during the Games will be low. The vector is not especially efficient in transmitting Zika as it’s harder to transmit than some other viruses.</p>
<p>The risk of infection through sex is <a href="https://theconversation.com/zika-via-sex-and-blood-how-worried-should-we-be-54174">infinitely lower</a>: the promotion of so-called <a href="https://theconversation.com/antiviral-condoms-will-help-protect-australian-olympians-from-stis-heres-how-59467">“Zika-proof” condoms</a> (special HIV-proof condoms have not been marketed) is an extraordinary example of capitalising on fear.</p>
<p>Sex and birth deformities make news, and so do medical breakthroughs. Mosquito control rarely does. Mosquito control for Zika is difficult, because <em>Aedes aegypti</em> prefers to graze on humans at dawn, late afternoon and early evenings; it is therefore perfectly adapted to spread any virus. </p>
<p>Images in the media of militarised mosquito-control programs evoke the successful campaigns against the same vectors in the Americas from the 1920s to 1950s to fight yellow fever, But fogging and spraying breeding sites is expensive and requires quick action before the vector develops insecticide resistance and so outwits the strategy. </p>
<p>The most effective intervention is to prevent exposure by reducing breeding sites in urban areas – getting rid of old spare tyres, removing water in the saucers of houseplants, and so on – and by humans reducing the likelihood of being bitten through wearing protective clothing and mosquito repellent. So rather than avoiding Rio, we can probably follow the logic of the epidemiology and take the risk.</p>
<img src="https://counter.theconversation.com/content/61810/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>Recently two events concerning the Zika epidemic coincided: two potential vaccines against the virus were declared a success when used in mice, and Jason Day withdrew from the Olympic Games.Lenore Manderson, Visiting Distinguished Professor of Environmental Studies, Brown University, USA, and Distinguished Professor, Public Health and Medical Anthropology, University of the WitwatersrandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/603962016-06-03T09:28:27Z2016-06-03T09:28:27ZShould Zika really stop you going to the Rio Olympics? Here are the facts<figure><img src="https://images.theconversation.com/files/124997/original/image-20160602-23270-cxexrd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Cidade maravilhosa.</span> <span class="attribution"><a class="source" href="http://www.shutterstock.com/cat.mhtml?lang=en&language=en&ref_site=photo&search_source=search_form&version=llv1&anyorall=all&safesearch=1&use_local_boost=1&autocomplete_id=&searchterm=Rio&show_color_wheel=1&orient=&commercial_ok=&media_type=images&search_cat=&searchtermx=&photographer_name=&people_gender=&people_age=&people_ethnicity=&people_number=&color=&page=1&inline=328110866">Aleksandar Todorovic/Shutterstock.com</a></span></figcaption></figure><p>Over 200 academics from around the world have now signed <a href="http://rioolympicslater.org/">an open letter</a> to the Director-General of the World Health Organisation (WHO) calling for the Olympics and Paralympics in Rio de Janeiro to be postponed or moved to another venue, owing to the threat posed by the ongoing Zika virus pandemic. The evidence concerning Zika virus so far, however, does not justify this course of action. The <a href="http://rioolympicslater.org/">RioOlympicsLater.org</a> authors misunderstand the nature of Zika virus, its history since its discovery in 1947, and also the relative risk posed by Zika virus versus other risks affecting any large event in a tropical country. </p>
<p>The letter begins by referring to the movement of the <a href="http://www.fifa.com/news/y=2003/m=5/news=sars-fifa-executive-decides-relocate-fifa-women-world-cup-2003-87152.html">2003 Women’s World Cup</a> from China to the USA owing to the outbreak of SARS, and the disruption of the <a href="http://www.nytimes.com/2014/11/12/sports/soccer/morocco-wont-host-africa-cup-of-nations-because-of-ebola-fears.html?_r=0">African Cup of Nations</a> schedule during the Ebola epidemic. Neither of these is, however, a valid comparison. </p>
<p>Both <a href="http://onlinelibrary.wiley.com/doi/10.1046/j.1365-3083.2003.01302.x/abstract;jsessionid=5EC933F85FDD4A286A7376B1DEE53824.f02t03">SARS</a> and <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4870382/">Ebola</a> were high-mortality diseases. Also, SARS was a completely new pathogen. Mortality in Zika is very low, and where deaths occur they are often due to complications of <a href="http://www.nhs.uk/Conditions/Guillain-Barre-syndrome/Pages/Introduction.aspx">Guillain-Barre Syndrome</a> rather than a direct result of the virus’s usual symptoms.</p>
<p>The real concern with Zika is <a href="https://theconversation.com/explainer-what-is-microcephaly-and-what-is-its-relationship-to-zika-virus-54049">microcephaly</a> and other damaging effects on foetuses via infection in pregnant women. But the authors’ statement that “Zika virus harms health in ways that science has not observed before” is not correct. <a href="http://www.ncbi.nlm.nih.gov/pubmed/27180225">Recent experiments</a> on laboratory mice, on brain <a href="http://www.ncbi.nlm.nih.gov/pubmed/27118425">organoids</a> (small balls of nervous cells that have <a href="https://www.technologyreview.com/s/535006/brain-organoids/">some of the structure and properties of developing brains</a>) and in brain tissue culture, as well as <a href="http://www.ncbi.nlm.nih.gov/pubmed/27028667">detailed observation</a> of the signs and symptoms of Zika-associated microcephaly in foetuses and infants, show that Zika <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4878297/">can be categorised with other TORCH-syndrome pathogens</a>. </p>
<p>TORCH is an acronym for “TOxoplasma, Rubella, Cytomegalovirus, Herpes”, <a href="http://rarediseases.org/rare-diseases/torch-syndrome/">all agents which cause similar defects in foetuses</a> when the mothers are exposed in pregnancy. Zika is the only TORCH-like pathogen that is spread by mosquito bites, but based on what we have seen so far, there is no reason to think that Zika is particularly virulent. If one insists on drawing comparisons with other diseases, Zika is not the new Ebola, but the new <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4316306/">rubella</a>. </p>
<p>The letter also claims that “most of South Asia and Africa” are “as yet unaffected places”. That is not true either. Many <a href="http://jgv.microbiologyresearch.org/content/journal/jgv/10.1099/jgv.0.000381#tab2">studies</a>, going back to the 1940s, have shown that humans, and often also monkeys, in several African and Asian countries have antibodies to the Zika virus, and we have direct evidence of Zika circulating in both <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3321795/">West Africa</a> and <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4866850/">South East Asia</a> within the last ten years. These studies need to be repeated to determine the current levels, but it is very likely that many parts of the tropical world have already seen Zika virus in the past and there will probably be considerable herd immunity to the local Zika variant in the human population. </p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/124999/original/image-20160602-23291-35owpc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/124999/original/image-20160602-23291-35owpc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/124999/original/image-20160602-23291-35owpc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/124999/original/image-20160602-23291-35owpc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/124999/original/image-20160602-23291-35owpc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/124999/original/image-20160602-23291-35owpc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/124999/original/image-20160602-23291-35owpc.jpg?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">The rubella virus.</span>
<span class="attribution"><a class="source" href="http://www.shutterstock.com/pic-208188670/stock-photo-rubella-german-measles.html?src=fLi9iCGaqf9D3L15SdAqTQ-1-0">decade3d - anatomy online/Shutterstock.com</a></span>
</figcaption>
</figure>
<p>Will that previous exposure be protective against more exotic strains of Zika? The likely answer is “yes”. The Brazilian and African varieties of Zika are about 12-13% different in terms of the <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3289602/">genetic variants accumulated</a> since their last common ancestor. The <a href="http://www.ncbi.nlm.nih.gov/pubmed/25545072">corresponding figure</a> for yellow fever virus, another member of the flavivirus family that includes Zika, is just under 22%. Yet a single <a href="http://www.nhs.uk/Conditions/yellow-fever/Pages/prevention.aspx">yellow fever vaccination</a> will protect against all variants of yellow fever and for a long period of time, so it would be very unusual if exposure to African or South-East Asian Zika did not similarly generate immunity against Brazilian Zika.</p>
<p>Brazil has many of the typical diseases found in the tropical world, including <a href="http://www.who.int/malaria/travellers/en/">malaria</a> and <a href="http://www.nhs.uk/Conditions/dengue/Pages/Introduction.aspx">dengue</a> as well as <a href="http://www.avert.org/professionals/hiv-around-world/latin-america/brazil">levels of HIV</a> about <a href="http://www.avert.org/professionals/hiv-around-world/western-central-europe-north-america/uk">three times higher</a> than the UK. These are things that travellers and athletes need to prepare for. All are clinically more serious than Zika, but none has been proposed as a reason to cancel the event.</p>
<p>There is no major event that is ever 100% safe, and that especially applies to major events in tropical countries. When Zika is seen as it should be, as an insect-borne rubella-like agent, the proper perspective for prevention becomes evident. </p>
<p>Pregnant women, those planning pregnancy and those predisposed to Guillain-Barre syndrome perhaps would be best advised to stay away. Other groups simply need to monitor their health carefully during their visit, use insect repellent and avoid risky sexual behaviour – and thereby also reduce their risk of catching HIV in the process. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/125002/original/image-20160602-23270-1x1gkji.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/125002/original/image-20160602-23270-1x1gkji.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/125002/original/image-20160602-23270-1x1gkji.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/125002/original/image-20160602-23270-1x1gkji.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/125002/original/image-20160602-23270-1x1gkji.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/125002/original/image-20160602-23270-1x1gkji.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/125002/original/image-20160602-23270-1x1gkji.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">
<figcaption>
<span class="caption">Go, but take the precautions.</span>
<span class="attribution"><a class="source" href="http://www.shutterstock.com/dl2_lim.mhtml?src=NSfsObRvTSMfWCGAbjYbaA-1-11&clicksrc=download_btn_inline&id=295527683&size=medium_jpg&submit_jpg=">lazyllama / Shutterstock.com</a></span>
</figcaption>
</figure>
<p>The <a href="https://www.gov.uk/foreign-travel-advice/brazil/health">travel advice</a> for the topics has not changed much because of Zika, unless you are pregnant or starting a pregnancy soon. The one new important point is that all travellers should <a href="http://apps.who.int/iris/bitstream/10665/204421/1/WHO_ZIKV_MOC_16.1_eng.pdf">abstain from unprotected sex for 60 days</a> following their return, since a Zika infection often does not have symptoms. Everyone who has been in a Zika area needs to assume that they may have been infected. </p>
<p>More importantly, all travellers with a fever or rash, or both, during or after their trip need to go to their doctor. But the first test will be for malaria rather than Zika, because the really important and dangerous tropical diseases must take priority. If these principles are observed, there is no reason why the Olympics cannot take place.</p><img src="https://counter.theconversation.com/content/60396/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Derek Gatherer is affiliated with the WHO Expert Committee On Biological Standardization as a participant in their project "WHO collaborative study to assess the suitability of an interim standard for antibodies to Ebola virus"</span></em></p>Academics have sent an open letter to the World Health Organisation calling for the Olympics to be postponed or moved because of the Zika threat. They’re overreacting.Derek Gatherer, Lecturer, Lancaster UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/594052016-05-16T10:37:46Z2016-05-16T10:37:46ZIs the Zika panic over?<p>Towards the end of last year, and over the first months of 2016, there were alarming reports of the <a href="http://www.bbc.co.uk/news/world-us-canada-35425731">explosive spread</a> of Zika virus infection in South America. As many as <a href="http://apps.who.int/iris/bitstream/10665/204348/1/zikasitrep_5Feb2016_eng.pdf">1.5m Brazilians</a> were thought to have contracted the virus. More, worrying still, there were reports of <a href="http://www.reuters.com/article/us-health-zika-brazil-idUSKCN0WV2I3">thousands of cases</a> of congenital microcephaly – infants born with abnormally small heads because of brain damage in the womb. Each week there appeared to be more reports and larger numbers of infants affected.</p>
<p>But the latest estimates from Brazil have reversed this trend. Last week, the total number of confirmed and suspected cases of Zika microcephaly is <a href="http://uk.reuters.com/article/us-health-zika-brazil-idUKKCN0Y22U4">reported to be 4,759</a>, 500 less than two months ago.</p>
<p>Why are the numbers of cases falling? Does this mean that earlier reports about Zika were wrong? Is the Zika panic over?</p>
<h2>Missed diagnosis</h2>
<p>One possibility is that microcephaly previously was underdiagnosed in Brazil. Prior to 2015, there were <a href="http://www.thelancet.com/pb/assets/raw/Lancet/pdfs/S0140673616002737.pdf">around 200 cases</a> reported per year in Brazil. However, this rate appears strikingly low. International studies suggest that microcephaly (in the absence of Zika virus) occurs in approximately <a href="http://news.nationalgeographic.com/2016/03/160307-zika-virus-microcephaly-brazil-science/">six out of every 10,000</a> newborn infants. Based on Brazil’s birth rate of 2.9m babies per year, we would expect there to be 1,700 cases per year.</p>
<p>So part of the initial surge in cases may have been due to recognition of cases of microcephaly that weren’t necessarily related to Zika infection. </p>
<h2>Confirming cases</h2>
<p>Did the intense attention on microcephaly lead to overdiagnosis?</p>
<p>The <a href="http://combateaedes.saude.gov.br/images/sala-de-situacao/informe_microcefalia_epidemiologico25.pdf">latest document</a> from the Brazilian health ministry shows that 7,438 cases of microcephaly had been notified up to May 7. Of the half that have been investigated so far, only about one third (about 1,300 cases) were confirmed as real cases of Zika microcephaly.</p>
<p>This points to the challenge of getting the diagnosis right. Babies can have small heads for a number of reasons, so it isn’t surprising that some cases turned out not to be due to Zika.</p>
<h2>Shifting cut-offs</h2>
<p>Next, the definition of microcephaly in Brazil has <a href="http://www.thelancet.com/pb/assets/raw/Lancet/pdfs/S0140673616002737.pdf">changed</a>. Before December 2015, microcephaly was defined as a head circumference at birth of less than 33cm. In December, experts decided that this was too generous: it would classify <a href="http://www.thelancet.com/pb/assets/raw/Lancet/pdfs/S0140673616002737.pdf">more than 600,000</a> newborn infants in Brazil a year as microcephalic, even though most of these children will be functionally normal. Subsequently, the Pan-American Health Organisation has recommended smaller cut-offs for female babies (who are usually smaller at birth), while another group has recommended the use of newly developed growth standards, the <a href="https://intergrowth21.tghn.org">Intergrowth charts</a>. So another reason that cases might have fallen is because criteria for diagnosing microcephaly have become tighter.</p>
<h2>Statistically normal</h2>
<p>The question of which cut-off we should use to define microcephaly overlaps with a wider philosophical issue – how do we <a href="http://plato.stanford.edu/entries/health-disease/">define disease</a> or disability? Some conditions are defined by reference to what is <a href="http://philpapers.org/rec/BOOOTD">statistically normal</a> for a population. But does it make sense to say that infants whose head is smaller than usual have a “disease”? What we want to know is whether a baby has brain problems that might have been caused by the Zika virus. But some babies with a normal head size may have brain problems from Zika, while other infants may just have small heads because it <a href="http://patients.aan.com/news/?event=read&article_id=8273">runs in their family</a>. Determining what is statistically normal or out of the normal range may be useful for researchers, but <a href="http://www.bep.ox.ac.uk/__data/assets/pdf_file/0019/9307/Welfarist_Account.pdf">what matters ethically</a> is whether something affects our well-being.</p>
<p>There is also a trade-off with the use of different cut-offs for identifying medical conditions. Most cases identified using a strict definition will actually have a problem. But these strict definitions may also miss some cases. So it depends on whether we are more worried about healthy babies being wrongly diagnosed with microcephaly or babies with microcephaly not being diagnosed.</p>
<p>If we are conducting research into Zika it would be useful to have an initial generous case definition. That will identify as many cases as possible and enable the most information to be gained about the effects of the infection.</p>
<p>However, if we are concerned about the individual babies, it may be better to have a much stricter definition. One reason is because babies who have microcephaly in Brazil will potentially need further tests, particularly CT brain scans, that can have side effects for the babies. In a health system with limited resources it may be important to focus efforts on the most severe cases.</p>
<h2>Zika on the wane?</h2>
<p>We don’t know yet whether the reduced reports of Zika microcephaly means that the epidemic is tailing off. Some <a href="http://www.sciencedirect.com/science/article/pii/S1755436516300093">models of the illness</a> have predicted a fall in cases over the beginning of 2016. Reduced cases might be because of <a href="https://www.washingtonpost.com/world/the_americas/spread-of-zika-virus-appears-to-be-slowing-in-parts-of-latin-america/2016/03/31/9cbb4fc2-f5c2-11e5-958d-d038dac6e718_story.html">rising levels of immunity</a> to the virus. </p>
<p>However, there are also concerns about the spread of the virus to new areas, and new populations who aren’t immune, particularly with the Rio Olympics later this year and large numbers of travellers to Brazil. The other unanswered question is whether the cases of microcephaly are the tip of the iceberg. It is possible that Zika infection in pregnant women might cause more subtle brain problems in babies (for example causing deafness) that won’t be apparent for some time. So while the news about reduced cases of Zika microcephaly is reassuring, it is too early to relax. </p>
<hr>
<p><em>In conjunction with Oxford University’s <a href="http://blog.practicalethics.ox.ac.uk/">Practical Ethics</a> blog</em></p><img src="https://counter.theconversation.com/content/59405/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Dominic Wilkinson receives research funding from the Wellcome Trust.</span></em></p>The number of new Zika-related microcephaly cases in Brazil is falling. But it’s too early to relax.Dominic Wilkinson, Consultant Neonatologist and Director of Medical Ethics, University of OxfordLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/541912016-03-30T14:52:53Z2016-03-30T14:52:53ZEbola and Zika epidemics are driven by pathologies of society, not just a virus<figure><img src="https://images.theconversation.com/files/115593/original/image-20160318-4456-nrf54r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">An Ebola training exercise at Madigan Army Medical Center's Andersen Simulation Center, in the US.</span> <span class="attribution"><span class="source">John Liston/Army Medicine/ flickr</span></span></figcaption></figure><p><em>This article is a foundation essay. These are longer than usual and take a wider look at a key issue affecting society.</em></p>
<p>The global health threats posed by recent viral epidemics, such as avian flu, <a href="http://www.webmd.com/cold-and-flu/flu-guide/h1n1-flu-virus-swine-flu">H1N1</a>, <a href="http://www.who.int/mediacentre/factsheets/fs103/en/">Ebola</a> and <a href="http://www.cdc.gov/zika/about/index.html">Zika</a>, have been happening too frequently to be dismissed as coincidental. </p>
<p>Unless the global public health community invests in and develops better health systems that provide for the poor, such viruses will continue to spread and have severe effects.</p>
<p>The mosquito-borne Zika virus was declared a global public health <a href="http://www.who.int/mediacentre/news/statements/2016/emergency-committee-zika-microcephaly/en/">emergency</a> by the World Health Organisation in February 2016 due to an increase in the number of microcephaly cases in areas where the virus was found. Microcephaly is a birth defect where babies are born with abnormally small heads. A <a href="http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(16)00273-7/fulltext">causal link</a> between in-utero exposure to the Zika virus and microcephaly has not yet been proven.</p>
<p>This is the first time since the <a href="http://www.reuters.com/article/us-health-ebola-emergency-idUSKBN0G80M620140808">Ebola epidemic</a> hit Africa in 2014 that the World Health Organisation has declared a global health emergency. Although the speed with which the organisation reacted has been welcomed, mounting an emergency response is not sufficient to manage the spread of viral epidemics like that of Zika. </p>
<p>In the case of the <a href="http://apps.who.int/ebola/en/ebola-situation-report/situation-reports/ebola-situation-report-18-february-2015">Ebola outbreak</a>, after a long delay, the World Health <a href="http://www.who.int/dg/speeches/2015/executive-board-ebola/">Organisation</a> called for an urgent change in three main areas. These included: </p>
<ul>
<li><p>rebuilding and strengthening national and international emergency preparedness and response;</p></li>
<li><p>addressing the way new medical products are brought to market; and </p></li>
<li><p>strengthening the way in which the World Health Organisation operates during emergencies.</p></li>
</ul>
<p>But the response has not been far-reaching enough to prevent similar viral outbreaks. The Zika virus is proof of this. Environmental, social and economic factors cause populations not previously affected by a particular disease to be exposed to its virus. To tackle such outbreaks in future, these factors must be addressed. </p>
<h2>Containing the spread of a virus</h2>
<p>Outbreaks happen for two reasons: the daily conditions that negatively affect the health of a country’s inhabitants have not been addressed; and there are weak national health systems in place. There are several structural drivers that influence these, resulting in outbreaks and determining their severity. These include:</p>
<ul>
<li><p>the way populations move and migrate. This is compounded by generally poor access to (weak) health-care services, especially for migrant populations. </p></li>
<li><p>hybrid viruses that appear in food processing factories and increase the chances of human-animal interactions. </p></li>
<li><p>increased interaction between human and forest animals. This happens as indigent populations are forced deeper into forested areas to look for food.</p></li>
</ul>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/115594/original/image-20160318-4450-1ji6ct4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/115594/original/image-20160318-4450-1ji6ct4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=468&fit=crop&dpr=1 600w, https://images.theconversation.com/files/115594/original/image-20160318-4450-1ji6ct4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=468&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/115594/original/image-20160318-4450-1ji6ct4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=468&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/115594/original/image-20160318-4450-1ji6ct4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=588&fit=crop&dpr=1 754w, https://images.theconversation.com/files/115594/original/image-20160318-4450-1ji6ct4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=588&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/115594/original/image-20160318-4450-1ji6ct4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=588&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A transmission electron micrograph of the Ebola virus.</span>
<span class="attribution"><span class="source">Frederick A Murphy/ CDC Global/ flickr</span></span>
</figcaption>
</figure>
<p>This increased interaction is thought to be behind the spread of Ebola. Human beings were never the primary target of the virus. It is believed the virus was primarily found in a few species of <a href="http://www.theguardian.com/society/2014/aug/23/ebola-outbreak-blamed-on-fruit-bats-africa">fruit bats</a>, which live in the tropical rainforests of central Africa. </p>
<p>Although central Africa has been the site of all earlier major Ebola outbreaks, it is hundreds of kilometres from the epicentre of the latest epidemic, which took place in West Africa. The geographic spread may be explained by poverty forcing people deeper into the forests in search of food, where they came into contact with the fruit bats or other animals infected by the bats.</p>
<p>How is the recent explosive Ebola outbreak explained? The answer lies not in the pathology of the disease but in the pathology of society, and the global political and economic architecture. </p>
<h2>Economic exploitation is partly to blame</h2>
<p>The spread of the Ebola epidemic was the result of poverty and the ruthless exploitation of the region’s natural resources. Those afflicted, at least initially, were typically the poorest – those forced, by scarcity, to look for food in the forests, where they came into contact with animals harbouring the virus. </p>
<p>Economic exploitation also resulted in under-resourced and weak health systems that could not contain the spread of the virus.</p>
<p>Take Sierra Leone, for instance. Its iron ore mining industry has rapidly expanded, fuelling economic growth in the country of 20% in 2013, according to the <a href="http://www.imf.org/external/pubs/ft/scr/2013/cr13330.pdf">International Monetary Fund</a>. Interest in its largely untapped mineral resources sparked a flood of investment a decade after the end of the devastating 1991 to 2002 civil war. The country’s economic growth rate is ranked among the highest in the world. </p>
<p>Yet in 2010 the country’s mining industry contributed almost 60% of exports but only 8% of government revenue. In 2011, only one of the major mining firms in the country was paying corporate income tax, while none of the top five was reporting profits despite a boom in mineral exports. </p>
<p>Similarly, both Liberia and Guinea have been heavily targeted by foreign companies. Liberia currently has the highest ratio of <a href="http://globaledge.msu.edu/countries/liberia/economy">foreign direct investment</a> to gross domestic product in the world. This largely is the result of foreign ownership of rubber production companies. </p>
<p>In Guinea, the area affected by Ebola attracted agribusiness shortly before the outbreak. In 2010, the British-backed <a href="http://www.farmlandgrab.org/post/view/18263">Farm Land of Guinea Limited</a> bought huge tracts of land for maize and soybean cultivation. And an Italian energy company has bought more than <a href="https://farmingpathogens.wordpress.com/2014/04/23/neoliberal-ebola/">700,000 hectares</a> for biofuel crops.</p>
<p>These countries’ dependence on extractive industries such as mining and logging, and financial losses due to tax evasion have left them impoverished and contributed to under-investment in – and the severe weakness of – their health systems. </p>
<h2>Weak health systems</h2>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/115595/original/image-20160318-4450-16ezpf2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/115595/original/image-20160318-4450-16ezpf2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/115595/original/image-20160318-4450-16ezpf2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/115595/original/image-20160318-4450-16ezpf2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/115595/original/image-20160318-4450-16ezpf2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/115595/original/image-20160318-4450-16ezpf2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/115595/original/image-20160318-4450-16ezpf2.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">Volunteer burial teams in Guinea disinfect themselves after carrying the body of an Ebola victim.</span>
<span class="attribution"><span class="source">UN Photo/Martine Perret</span></span>
</figcaption>
</figure>
<p>It is no accident that the Ebola epidemic affected three of the poorest countries in the world. </p>
<p>Liberia, Guinea and Sierra Leone number 175, 179 and 183, respectively, out of 187 countries on the United Nations’ <a href="http://hdr.undp.org/sites/default/files/hdr14-report-en-1.pdf">Human Development Index</a>. Their health systems are ineffective and almost nonexistent in many regions, affecting management of diseases. </p>
<p>In Sierra Leone, for example, in the four months following the outbreak of Ebola, 848 people were infected by the virus and 365 died. And in an <a href="http://www.bloomberg.com/bw/articles/2014-08-11/the-ebola-outbreak-shows-why-the-global-health-system-is-broken">average four months</a>, the country sees about 650 deaths from meningitis, 670 from tuberculosis, 790 from HIV/AIDS, 845 from diarrhoea and more than 3,000 from malaria. </p>
<p>Such deaths have been occurring for decades, but with no previous focus on these countries. </p>
<p>Furthermore, in these three countries there is a persistent crisis of human resources, with a serious deficit of health workers, especially in rural areas. This is a result of long-term underproduction and continuing migration. More Liberian and Sierra Leonean medical doctors work in the US and UK than in their home countries. </p>
<h2>How to solve the problem</h2>
<p>As a start, it is important to focus on crisis response. The World Health Organisation had a feeble initial response to Ebola, in part, because of cuts of more than 50% in its outbreak and response budget – the very budget line needed to respond to Ebola. This dropped from US$469 million in 2012/2013 to <a href="https://www.washingtonpost.com/news/monkey-cage/wp/2014/08/08/can-the-world-health-organization-lead-do-we-want-it-to/">US$228 million</a> in 2014/2015, mainly because member states, particularly rich ones, failed to pay their financial contributions.</p>
<p>But managing viral epidemics requires that authorities look beyond the immediate crisis response. A major and sustained investment in human resources is required. Initially, this will require greatly increased donor assistance. </p>
<p>In the medium term, there is an urgent need to strengthen health systems in the region. Although talk of “health systems strengthening” has become commonplace there is little evidence of this in several African countries.</p>
<p>But the most sustainable solution requires fundamental changes to economic and power relations between these countries and the capitalist economies and enterprises that continue to bleed them dry, often with the collusion of local officials and elites. </p>
<p><em>Amit Sengupta, associate co-ordinator of the People’s Health Movement, was involved in the formulation of this article.</em></p><img src="https://counter.theconversation.com/content/54191/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>David Sanders receives funding from the South African National Research Foundation. He is affiliated with the People's Health Movement, a global social movement. </span></em></p>To tackle Zika and other viral outbreaks, we need to focus not only on the pathology of the disease, but also on the global political and economic architecture.David Sanders, Emeritus Professor, School of Public Health, University of the Western CapeLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/563502016-03-28T19:08:07Z2016-03-28T19:08:07ZNew mosquito threats shift risks from our swamps to our suburbs<figure><img src="https://images.theconversation.com/files/116011/original/image-20160322-32291-14rwta1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A new arrival in Australian backyards may increase the risks of mosquito-borne disease outbreaks.</span> <span class="attribution"><span class="license">Author provided</span></span></figcaption></figure><p>The outbreak of <a href="http://www.cdc.gov/zika/">Zika virus</a> has refocused the attention of health authorities on mosquito-borne disease. The virus has now been reported from almost 40 countries and the list is growing with imported cases of the disease popping up across the globe, from Norway to north Queensland.</p>
<p>Notwithstanding the millions of cases of disease predicted to occur this year, the <a href="http://www.nytimes.com/2016/03/16/health/zika-virus-microcephaly-rate.html?smid=tw-share&_r=0">ever strengthening link</a> between Zika virus and birth defects is cause for ongoing concern.</p>
<p>Zika virus may be in the headlines but the burden of other mosquito-borne diseases, such as <a href="http://www.who.int/topics/dengue/en/">dengue fever</a>, should not be overlooked.</p>
<p>Mosquito bites are the critically important route of transmission of Zika and other viruses but when it comes to spreading these pathogens, not all mosquitoes are equal. The secret is in the spit.</p>
<h2>Why do mosquitoes suck?</h2>
<p>Only female mosquitoes bite. Blood provides a perfect nutritional boost for egg development but who or what mosquitoes bite varies with species. Many mosquitoes opportunistically bite whatever warm blooded creature is about. That includes people. <a href="https://theconversation.com/health-check-why-mosquitoes-seem-to-bite-some-people-more-36425">Some people more than others</a>.</p>
<p>Mosquitoes aren’t “dirty syringes”. They don’t pass on pathogens through infected droplets of blood. When mosquitoes insert their mouthparts into our skin, it’s not like they’re sticking in a drinking straw. There are some tubes that suck and some tubes that spit. The spit they inject contains a mix of chemicals, some help get the blood flowing and some make their bite a little less noticeable. Unfortunately, that spit may also contain virus.</p>
<p>If a mosquito sucks up a virus-filled blood meal, that virus must then escape the gut and spread throughout the body of the mosquito until the salivary glands are infected. This process can take from a few days to over a week. But time isn’t all that matters.</p>
<p>There is no malicious intent in mosquitoes transmitting viruses. The viruses are simply taking advantage of the mosquitoes’ evolutionary initiative to exploit vertebrate blood. The viruses don’t make the mosquito sick, that wouldn’t make sense as the virus wants to make sure it makes it to the next host. Unfortunately, humans can fall ill following the injection of a mouthful of virus filled mozzie spit.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/116013/original/image-20160322-32327-1krj7mi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/116013/original/image-20160322-32327-1krj7mi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/116013/original/image-20160322-32327-1krj7mi.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/116013/original/image-20160322-32327-1krj7mi.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/116013/original/image-20160322-32327-1krj7mi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/116013/original/image-20160322-32327-1krj7mi.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/116013/original/image-20160322-32327-1krj7mi.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">Mosquitoes can be relentless in their pursuit of blood! Source: Author Provided.</span>
</figcaption>
</figure>
<h2>Many different mosquitoes, many different risks</h2>
<p>There are dozens of mosquitoes in Australia that can transmit local pathogens such as <a href="http://journals.plos.org/plospathogens/article?id=10.1371/journal.ppat.1005070">Ross River virus</a>. Most of these <a href="http://www.publish.csiro.au/pid/6391.htm">mosquitoes</a> are found in our local wetlands. But when it comes to Zika virus, there is only one mosquito that poses a threat of <a href="https://theconversation.com/does-zika-virus-pose-a-threat-to-australia-53557">local transmission</a>. That mosquito is <em>Aedes aegypti</em>, commonly known as the Yellow Fever mosquito, and it loves water-holding containers in suburban backyards in northern Queensland.</p>
<p>There is little doubt <em>Aedes aegypti</em> is playing the critical role in the spread of Zika virus in South America. Currently, it poses the biggest threat of an outbreak in Australia too. Not just for Zika but other viruses, <a href="http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0134975">including chikungunya</a>.</p>
<p>The absence of <em>Aedes aegypti</em> from Australia’s major metropolitan regions greatly reduces the risk of a major outbreak but a risk still exists where this mosquito is present. Local authorities have been on alert following the detection of infected travellers in <a href="http://www.townsvillebulletin.com.au/news/first-case-of-zika-confirmed-in-townsville/news-story/6c04724b0fe3df71223de8e999b3e07b">Townsville</a> and <a href="http://www.abc.net.au/news/2016-02-24/zika-virus-man-positive-rockhampton-queensland-health/7197722">Rockhampton</a> but there have still not been any confirmed cases of local transmission in Australia.</p>
<h2>More mosquitoes on the way</h2>
<p>Mosquitoes capable of spreading Zika virus are knocking on the doors of our major cities. <em>Aedes aegypti</em> has been detected by the <a href="http://www.agriculture.gov.au/about/media-centre/media-releases/managing-exotic-mosquitoes-at-the-border">Department of Agriculture and Water Resources</a> at <a href="http://www.couriermail.com.au/news/queensland/aedes-aegypti-mosquito-detected-at-brisbane-airport/news-story/ea6b6c743a8c991107a5728d908870d5">Brisbane</a>, <a href="http://www.dailytelegraph.com.au/news/nsw/zika-virus-mosquitoes-found-in-sydney-airport-increases-insecticide-spraying-of-incoming-passengers/news-story/997365490643371ee6cea1578e0522d5">Sydney</a>, <a href="http://www.theage.com.au/victoria/mosquitoes-that-spread-dengue-and-yellow-fever-found-at-melbourne-airport-20140315-34tno.html">Melbourne</a> and <a href="http://www.dailymail.co.uk/news/article-3041370/Exotic-mosquitoes-South-East-Asia-carrying-crippling-diseases-discovered-Australian-airports-three-times-past-two-months.html">Perth</a> international airports in recent years. Although mosquitoes are sneaking onto flights out of tropical destinations they’ve never escaped our local airports and into surrounding suburbs. Even if they did, winter would likely <a href="https://www.mja.com.au/journal/2009/190/5/dengue-and-climate-change-australia-predictions-future-should-incorporate">stop them in their tracks</a>.</p>
<p>But while the limited distribution and intolerance of cold climates of <em>Aedes aegypti</em> may protect Australia from major outbreaks, this buffer could be dramatically eroded should a new mosquito species make its way to mainland Australia. That mosquito is the Asian Tiger Mosquito, <em>Aedes albopictus</em>.</p>
<p><em>Aedes albopictus</em> is one of the most <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2212601/">pestiferous mosquitoes</a> on the planet. It is widespread in many parts of the world, commonly found in and around urban areas, can spread a range of pathogens and is a severe nuisance biting pest. Most importantly, unlike <em>Aedes aegypti</em>, it is not restricted to tropical regions and can thrive in cooler climates. It is this mosquito that has caused outbreaks of <a href="https://cameronwebb.wordpress.com/2014/09/15/what-can-the-outbreak-of-dengue-in-japan-tell-us-about-future-mosquito-borne-disease-risk/">dengue in Japan</a> and <a href="http://www.eurosurveillance.org/ViewArticle.aspx?ArticleId=3260">chikungunya virus in Europe</a>. It may also play a role in the <a href="http://www.thelancet.com/journals/laninf/article/PIIS1473-3099%2816%2900176-6/fulltext">spread of Zika virus</a>.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/116101/original/image-20160322-32291-qeoyk4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/116101/original/image-20160322-32291-qeoyk4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/116101/original/image-20160322-32291-qeoyk4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/116101/original/image-20160322-32291-qeoyk4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/116101/original/image-20160322-32291-qeoyk4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/116101/original/image-20160322-32291-qeoyk4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/116101/original/image-20160322-32291-qeoyk4.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">Water-holding containers of various shapes and sizes could be a home of mosquitoes such as Aedes aegypti and Aedes albopictus. Source: Author Provided.</span>
</figcaption>
</figure>
<h2>Asian tigers and Australian backyards</h2>
<p>The mosquito has never been established on mainland Australia but it’s been buzzing about our borders for over a decade. A <a href="http://www.sciencedirect.com/science/article/pii/S2352771415300161">newly published review</a> shares insights from ten years of research and management of this mosquito. First discovered in the <a href="http://www.bioone.org/doi/abs/10.2987/8756-971X%282006%2922%5B358%3ADOAWIO%5D2.0.CO%3B2">Torres Strait in 2005</a>, authorities have been working hard to stop its spread to the mainland. Eradication was tried but proved impractical and risks of reintroduction required a different approach. Containment, particularly focused on potential pathways of movement into the mainland, is now the critical objective of current management strategies.</p>
<p>If the mosquito does make it to one of our major cities, could it become established? International experience suggests it will eventually. Research is critical to assess the local importance of this mosquito in driving outbreaks of disease.</p>
<p>Laboratory studies have shown the mosquito can transmit <a href="http://jme.oxfordjournals.org/content/51/3/661">local and exotic pathogens</a>. Cool climates of southern cities will be <a href="http://onlinelibrary.wiley.com/doi/10.1111/aec.12105/abstract">no barrier to the mosquito</a> and native mosquitoes that share the same types of habitats <a href="http://jme.oxfordjournals.org/content/52/3/375.abstract">won’t put up much of a fight</a> either. Local authorities must face the threat that this mosquito could become established in our major metropolitan regions. This has the potential to shift the playing field of mosquito control from our swamps to our suburbs.</p>
<p>Existing mosquito control and surveillance programs are generally directed towards local pathogens and mosquitoes mostly associated with local wetlands. These programs are not easily adapted to monitoring activity of exotic mosquitoes such as <em>Aedes aegypti</em> and <em>Aedes albopictus</em> and what works in controlling wetland mosquito populations is not easily applied to backyard habitats.</p>
<p>There is little doubt mosquito-borne disease will remain a concern into the future. Just last year New South Wales and Queensland experienced one of the <a href="https://theconversation.com/is-climate-change-to-blame-for-outbreaks-of-mosquito-borne-disease-39176">biggest outbreaks of Ross River virus disease</a> on record. But the risk of this disease is greatest at our city’s edges. </p>
<p>If <em>Aedes albopictus</em> finds a home here, there may well be greater risk in the heart of our suburbs and, significantly, from pathogens that pose far greater health risks. The last thing Australian authorities would want to battle with is outbreaks of dengue and chikungunay virus. Zika virus would just be another risk in the mix.</p><img src="https://counter.theconversation.com/content/56350/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Cameron Webb and the Department of Medical Entomology, NSW Health Pathology and University of Sydney, have been engaged by a wide range of insect repellent and insecticide manufacturers to provide testing of products and provide expert advice on mosquito biology. Cameron has also received funding from local, state and federal agencies to undertake research into mosquito-borne disease surveillance and management.</span></em></p>Zika virus may be in the headlines but the burden of other mosquito-borne diseases, such as dengue fever, should not be overlooked.Cameron Webb, Clinical Lecturer and Principal Hospital Scientist, University of SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/552002016-03-16T10:10:22Z2016-03-16T10:10:22ZZika and abortion: will the virus prompt Latin America to rethink abortion and birth control?<p>The Zika virus outbreak and its probable association with microcephaly in newborns are prompting <a href="http://www.theguardian.com/world/2016/feb/05/zika-virus-epidemic-abortion-birth-control-access-latin-america-united-nations">calls to loosen</a> Latin America’s strict abortion laws and make birth control more readily available. </p>
<p>Abortion is fully criminalized in six countries in the region. In El Salvador, for instance, <a href="http://prospect.org/article/what-happens-when-abortion-outlawed">women who have abortions can face prison</a>. In many other countries, including Brazil and Colombia, abortion is permitted only in cases of rape, incest or fetal impairment.</p>
<p>As Zika raises anxieties about babies born with significant medical problems, some physicians and reproductive health advocates think the virus should <a href="http://www.wired.com/2016/01/abortion-and-zika-south-america/">create another legal exception</a> for abortion.</p>
<p>Even though abortion is outlawed in much of Latin America, women still seek it out at legal and physical risk. In fact, <a href="http://dx.doi.org/10.1016/j.ijgo.2014.03.011">13 percent of maternal deaths</a> (the fourth highest cause) in the region can be attributed to unsafe abortions.</p>
<p>Concern about Zika could lead to real change for reproductive health for millions of women in the region. But this can happen only if the expansion of abortion and contraception is based on human rights and reproductive health equity, not driven primarily by fears of defective babies. </p>
<h2>Abortion is restricted in most of Latin America</h2>
<p>Abortion is fully criminalized, with no exceptions, in El Salvador, Chile, Dominican Republic, Haiti, Nicaragua and Suriname. In El Salvador, 30 to 40 women are serving prison sentences <a href="http://www.reproductiverights.org/sites/crr.civicactions.net/files/documents/IAD9794%20Repro%20Rights_web.pdf">for seeking abortions</a>. </p>
<p>In many other countries, including Argentina, Costa Rica, Bolivia, Brazil and Colombia, <a href="https://www.guttmacher.org/pubs/IB_AWW-Latin-America.pdf">abortion is permitted under certain circumstances</a>.</p>
<p>In Brazil, for instance, <a href="http://www.pri.org/stories/2016-01-28/zika-virus-has-reignited-brazil-s-abortion-debate">abortion has been allowed since 1940</a> in instances of <a href="http://dx.doi.org/10.1016/S0968-8080(12)40657-7">rape or endangerment to the woman</a>. Women who seek abortions outside these exceptions and the physicians who perform the procedure can be imprisoned. </p>
<p>In 2012, Brazil’s Supreme Court upheld anencephaly (the absence of parts of the brain and skull in the fetus) as a <a href="http://www.pri.org/stories/2016-01-28/zika-virus-has-reignited-brazil-s-abortion-debate">justifiable condition for the termination of a pregnancy</a>, creating a new exception. </p>
<p>Health officials in Brazil have suggested that women <a href="https://www.bostonglobe.com/news/world/2016/01/26/officials-brazil-urge-women-avoid-pregnancy-due-zika-virus/Ask7wAjozV0G6SCv80uK8N/story.html">avoid pregnancy until the Zika crisis is over</a>. While Brazilian women are using contraception at a slowly increasing rate, <a href="http://dx.doi.org/10.1016/S0968-8080(12)40657-7">up to 81 percent in 2006 from 78 percent in 1996</a>, there are significant class and regional divides when it comes to access.</p>
<p>In 2006, Colombia’s Constitutional Court issued <a href="http://dx.doi.org/10.1016/S0968-8080(14)44803-1">Decision C-355</a>, guaranteeing three health exceptions for abortion: when the woman’s health is endangered, when serious malformations make the fetus unviable or when the pregnancy has resulted from criminal acts such as rape or incest. The decision was based, in part, on action from two groups called Women’s Link Worldwide and <em>La Mesa</em>. </p>
<p>Now that <a href="http://www.nytimes.com/2016/02/16/world/americas/zika-virus-in-colombia-presents-complicated-choice-about-abortion.html?_r=0">Zika is spreading in Colombia</a>, affecting as many as <a href="http://www.npr.org/sections/goatsandsoda/2016/02/24/467983166/pregnant-women-whove-had-zika-and-their-doctors-watch-and-wait">6,300 pregnant women</a>, some physicians and women’s health advocates are eyeing the possibility of another exception. </p>
<p>While that possibility is debated, officials are urging women of childbearing age to avoid pregnancy, a suggestion as problematic as it is unrealistic. Colombia has <a href="http://www.guttmacher.org/pubs/Unintended-Pregnancy-Colombia.html">high levels of unplanned pregnancy</a>, and birth control is expensive. </p>
<p>El Salvador, Ecuador and Jamaica have made similar calls for <a href="http://www.bbc.com/news/world-latin-america-35388842">women to delay pregnancy</a>. </p>
<h2>Why is access to birth control and abortion so restricted?</h2>
<p>Up to one-half of sexually active women in Latin America <a href="http://rhrealitycheck.org/article/2012/01/25/what-is-state-abortion-rights-in-latin-america-and-caribbean/">have an unmet need for contraception</a>. <a href="https://www.guttmacher.org/pubs/journals/3704611.html">Up to 58 percent of pregnancies in Latin America</a> <a href="http://www.motherjones.com/politics/2016/01/latin-america-zika-virus-women-pregnancy-abortion">are unintended</a> (compared <a href="https://www.guttmacher.org/pubs/FB-Unintended-Pregnancy-US.html">to 45 percent</a> in the United States).</p>
<p>Many factors <a href="http://www.reproductiverights.org/sites/crr.civicactions.net/files/documents/IAD9794%20Repro%20Rights_web.pdf">explain why birth control is out of reach</a> for so many Latin American women. Cost can be a significant barrier to access, but it’s not the only one.</p>
<p>The Catholic Church and evangelical religions are stalwart opponents to abortion and contraception. Even when there is <a href="http://dx.doi.org/10.1016/S0968-8080(11)38597-7">growing public support of birth control and abortion</a>, legislatures have been exceedingly slow to enact change. </p>
<p>For instance, in the mid-2000s, <a href="http://dx.doi.org/10.1080/13876988.2013.785669">then-President Luiz Inácio Lula da Silva sought to expand abortion in Brazil</a>, casting it as an important public health issue. Despite rising public support, he could not obtain enough support from his own left-wing Worker’s Party (PT) to change existing law. </p>
<p>Judicial interpretation frequently invokes moral law about protecting the right to life from conception. For example, both Argentina’s Civil Code and Brazil’s Penal Code and Constitution uphold that <a href="http://dx.doi.org/10.1016/j.ijgo.2008.05.002">life commences at conception</a>. This has been invoked in a range of abortion cases.</p>
<p>Finally, mainstream media coverage of abortion tends to be negative and <a href="http://www.reproductiverights.org/sites/crr.civicactions.net/files/documents/IAD9794%20Repro%20Rights_web.pdf">reflects patriarchal values around motherhood and reproduction</a>.</p>
<p>These obstacles are why women’s rights groups and reproductive health advocates, like those who argued for exceptions in Colombia, have strategically used harm reduction and exception rationales to open wedges in ironclad abortion policies. </p>
<h2>Where is abortion legal in Latin America?</h2>
<p>Abortion is legal and accessible in just a few places in Latin America. </p>
<p>In 1979, Cuba fully legalized abortion and made it available as part of <a href="https://books.google.com/books?id=Du1nAwAAQBAJ&pg=PT74&dq=cuba+abortion+history&hl=en&sa=X&ved=0ahUKEwj40b7hkaXLAhWJ6yYKHQ70DhIQ6AEIMjAC#v=onepage&q=abortion&f=false">overall health services</a>. </p>
<p>In 1995, Guyana allowed women to <a href="http://www.cesruc.org/uploads/soft/130301/1-130301215449.pdf">obtain abortions on request</a> in the first eight weeks of pregnancy. After that, abortion is available under certain circumstances.</p>
<p>In 2007, following campaigns that involved women’s groups, supportive legislators and NGOs, Mexico City bucked national policy and <a href="http://dx.doi.org/10.2105/AJPH.2012.301202">decriminalized abortion in the first trimester</a>. The decision was based on <a href="http://dx.doi.org/10.1080/13876988.2013.785669">human rights, reproductive health and even sympathetic theological arguments</a>. </p>
<p>In 2012, Uruguay made abortion available upon request in the first 12 weeks of pregnancy, following a five-day period of reflection for the woman considering termination. Later-term abortions are permitted in instances of rape and when a women’s health is endangered. </p>
<p>The seeds for this change were planted in the mid-2000s with the implementation of a “harm reduction model,” which allowed women to induce abortions using drugs like Mifeprex. Although this law depended on the logic of health exception, it was passed amid increasing emphasis on health equity. Since its passage, maternal deaths due to abortion have decreased markedly in the country. Uruguay now has <a href="http://www.reproductiverights.org/sites/crr.civicactions.net/files/documents/IAD9794%20Repro%20Rights_web.pdf">the third lowest maternal death rate in the Americas</a> after Canada and the United States. </p>
<p>Not surprisingly, contraception also is more accessible and accepted in countries where abortion laws are less restrictive. For example, a 2014 Pew Research Center poll found that only <a href="http://www.pewforum.org/2014/11/13/chapter-5-social-attitudes/">five percent of people in Uruguay believe contraception is morally wrong, compared to 45 percent in El Salvador</a>. </p>
<h2>Underground abortions are a major public health problem</h2>
<p>Zika is a public emergency in Latin America, forcing nations to devote resources to halting its continued spread. But unsafe abortion is another public health crisis the region faces.</p>
<p>Latin America has the highest incidence of unsafe abortion in the world, resulting in <a href="http://apps.who.int/iris/bitstream/10665/75173/1/WHO_RHR_12.01_eng.pdf">approximately 1,100 maternal deaths per year</a>. According to the Guttmacher Institute, of the 4.4 million abortions performed in all of Latin America in 2008, <a href="https://www.guttmacher.org/pubs/IB_AWW-Latin-America.pdf">95 percent were unsafe</a>. About <a href="https://www.guttmacher.org/pubs/IB_AWW-Latin-America.pdf">760,000 women are hospitalized</a> for complications from these substandard procedures each year. </p>
<p>Many of the women harmed by lack of access to abortion are indigenous, low-income or live in rural areas. They may not have money nor the legal resources to obtain abortions in private clinics or to make a case for an exception based on rape or incest. </p>
<p>Indeed, <a href="http://www.motherjones.com/politics/2016/01/latin-america-zika-virus-women-pregnancy-abortion">1.6 million women are raped each year in Latin America</a>, making access to emergency contraception and abortion all the more critical. </p>
<p>The Zika outbreak has the potential to promote change in abortion and birth control policies across Latin America. Yet these reproductive health options should not be framed simply as solutions to the latest health crisis or the specter of babies with deformities. Women need contraception and access to safe, legal abortion whether they are living in an area where Zika is active, or not. </p>
<p>Following the lead of Uruguay and Mexico City, framing abortion and contraception in terms of human rights and reproductive health equity could help expand access to these critical services for millions of women.</p><img src="https://counter.theconversation.com/content/55200/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Alexandra Minna Stern 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>Better access to birth control and safe, legal abortions in Latin America could save lives. But carving out Zika-related exceptions in existing restrictions might not go far enough to achieve this.Alexandra Minna Stern, Professor of American Culture, Obstetrics and Gynecology, and Women's Studies; Director of the Center for Latin American and Caribbean Studies and the Brazil Initiative, University of MichiganLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/541132016-02-10T05:42:27Z2016-02-10T05:42:27ZWhat are the real risks of Zika?<figure><img src="https://images.theconversation.com/files/110920/original/image-20160210-3271-1g5vo2t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Even if Zika sometimes causes pregnant mothers to have babies with microcephaly, this does not necessarily mean every infected mother would have an affected baby. </span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/conifer/14951771097/">coniferconifer/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>Zika has raised alarm bells worldwide, prompting the World Health Organisation’s (WHO) <a href="https://theconversation.com/zika-emergency-status-a-cause-for-alert-not-alarm-54042">declaration</a> of a “public health emergency”, El Salvador’s dramatic recommendation that women delay pregnancy for two years, and the US Centres for Disease Control’s (CDC) recommendation that pregnant women <a href="http://www.cdc.gov/media/releases/2016/s0315-zika-virus-travel.html">consider postponing travel</a> to Zika-affected countries. </p>
<p>The concern is that Zika may cause microcephaly, a birth defect that leaves infants with smaller heads and/or incomplete brain development. </p>
<p>But despite all the hype, crucial scientific and ethical questions about the virus remain unanswered. Exactly how great is the risk that Zika infection during pregnancy would result in a baby with microcephaly? And what can or should be done to prevent this? </p>
<h2>Need for more and better data</h2>
<p>The belief that Zika might cause microcephaly is largely based on a recent spike in reported numbers of cases in Brazil. The virus has been detected in the amniotic fluid of pregnant women with microcephalic babies. There is also an apparent <a href="http://www.who.int/bulletin/online_first/16-170639.pdf">increase</a> in the severity of microcephaly (smaller head sizes) in Brazil. </p>
<p>However, estimates of microcephaly cases in Brazil are in the process of being <a href="http://www.usnews.com/news/world/articles/2016-01-27/brazil-270-of-4-120-suspected-microcephaly-cases-confirmed">revised down</a>. This suggests there may have been a transition from under-counting to over-counting of cases.</p>
<p>Other possible causes of increased microcephaly – infections such as rubella and <a href="https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/cytomegalovirus-cmv">cytomegalovirus</a> (a member of the herpes family), as well as malnutrition and heavy alcohol consumption – should also be considered. </p>
<p>The World Health Organisation admits it <a href="http://www.who.int/mediacentre/news/statements/2016/emergency-committee-zika-microcephaly/en/">has not yet been scientifically proven</a> that Zika causes microcephaly.</p>
<h2>Assessing the risk</h2>
<p>Even if Zika sometimes causes pregnant mothers to have babies with microcephaly, this does not necessarily mean every infected mother would have an affected baby. </p>
<p>Assessing the risks of Zika thus requires knowing the percentage of infected pregnant women who give birth to babies with microcephaly. If this percentage is higher than the percentage of uninfected women (which has not, to date, been shown), it might be safe to conclude that Zika increases the relative risk of microcephaly. </p>
<p>Even then, the absolute risk that an infected pregnant woman will give birth to an affected infant might still be quite low. </p>
<p>Microcephaly usually affects only a <a href="http://www.nature.com/news/zika-virus-brazil-s-surge-in-small-headed-babies-questioned-by-report-1.19259">tiny number of newborn children</a>, perhaps around 0.02% (or 2 in 10,000). </p>
<p>If, hypothetically, it turns out that infection with Zika makes a pregnant woman 100 times more likely (than the average uninfected pregnant woman) to give birth to a baby with microcephaly, only (around) 2% of infected women would be expected to have affected babies. This could have significant public health impacts.</p>
<p>It is questionable, however, whether a 2% chance that infected pregnant women would end up with affected fetuses would provide a good reason for all women in countries such as El Salvador or Brazil to delay pregnancy. </p>
<p>It remains to be seen, but the absolute risk that an infected pregnant mother gives birth to an affected baby might turn out to be (much) lower or higher than 2%.</p>
<h2>Selective abortion</h2>
<p>Regardless of how high the absolute risk of Zika turns out to be, prenatal ultrasound testing could enable the detection and termination of severely affected fetuses. </p>
<p>However, such services are often not available. For religious reasons, abortion laws are especially <a href="https://www.hrw.org/legacy/backgrounder/wrd/wrd0106/">restrictive</a> in Latin America, where Zika is most prevalent. </p>
<p>The poor are often less likely to have easy access to prenatal ultrasound testing. Even with ultrasound, microcephaly is <a href="http://www.huffingtonpost.com.au/entry/zika-virus-us-abortion-disability_us_56b2601be4b04f9b57d83192?section=australia">difficult to detect in early pregnancy</a>, which means abortion, if used, would need to be in the second or third trimester.</p>
<p>Abortion, of course, is ethically controversial. In addition to cases of rape and when pregnancy threatens the life or health of the mother, however, abortion to prevent birth of severely disabled offspring is one of the cases where it is most commonly considered to be ethically acceptable. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/110921/original/image-20160210-3265-6f02tn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/110921/original/image-20160210-3265-6f02tn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=398&fit=crop&dpr=1 600w, https://images.theconversation.com/files/110921/original/image-20160210-3265-6f02tn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=398&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/110921/original/image-20160210-3265-6f02tn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=398&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/110921/original/image-20160210-3265-6f02tn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/110921/original/image-20160210-3265-6f02tn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/110921/original/image-20160210-3265-6f02tn.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">
<figcaption>
<span class="caption">Though declared a public health emergency, Zika is not expected to cause many deaths, and need not affect many births.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/agenciabrasilia/23200815303/">Agência Brasília/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Abortion to prevent microcephaly, on the other hand, is not a decision to be taken lightly. Microcephaly varies widely in severity: some microcephalic children develop severe intellectual impairment, some are moderately affected, and a small proportion have few, if any, impairments. </p>
<p>Inclusive social policies should aim to provide a high quality of life for all children. But, equally, all women should have access to prenatal care (including testing for microcephaly, Zika and other infections) and be free to make their own decisions regarding termination of pregnancy. It’s time for Brazil to revise its highly restrictive <a href="http://www.nytimes.com/2016/02/04/world/americas/zika-virus-brazil-abortion-laws.html">abortion policy</a>.</p>
<h2>Protecting the vulnerable</h2>
<p>The rates of Zika, like those of many infections and other risk factors for microcephaly, are highest in disadvantaged populations. These people already lack access to health care and disease control. Even simple measures to avoid mosquitoes (and sexual transmission) are often unavailable to those living in poverty. </p>
<p>Improved public health data collection (surveillance) and increased access to prenatal care (including testing for microcephaly, Zika and other infections) would help clarify the risks of Zika, enable prevention of birth of affected babies (for those who might choose abortion) and remedy unjust health outcomes more generally. </p>
<p>The most worrying aspect of the Zika crisis is arguably that it might be a sign of things to come. The same dynamics that are driving this outbreak also contribute to emergence and re-emergence of other infectious diseases. Urbanisation, deforestation, globalisation, inequality between rich and poor, and climate change all play a role. </p>
<p>Climate change <a href="https://theconversation.com/is-climate-change-to-blame-for-outbreaks-of-mosquito-borne-disease-39176">promotes</a> mosquito-borne diseases such as dengue and chikungunya, which has recently spread to the continental United States. Other climate-sensitive mosquitoes carry malaria, which causes hundreds of thousands of childhood deaths every year. </p>
<p>Increased rates of mosquito-borne disease should compel stronger international action on climate change and investment in infectious disease surveillance, research, treatment and prevention. The World Health Organisation’s declaration of a public health emergency will hopefully lead to such outcomes.</p><img src="https://counter.theconversation.com/content/54113/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Euzebiusz Jamrozik receives funding from an Australian Postgraduate Award (PhD Scholarship). </span></em></p><p class="fine-print"><em><span>Michael Selgelid 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>Despite all the hype around Zika, crucial questions remain unanswered. How great is the risk that infection during pregnancy would result in a baby with microcephaly? And what can be done to prevent this?Michael Selgelid, Director, Centre for Human Bioethics; Director, World Health Organization Collaborating Centre for Bioethics, Monash UniversityEuzebiusz Jamrozik, PhD Candidate, Centre for Human Bioethics, Monash UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/537162016-02-05T15:57:20Z2016-02-05T15:57:20ZProving that the Zika virus causes microcephaly<p>When the Zika virus was first discovered in Uganda in the 1940s, it was thought to be harmless. It caused a rash and, in some cases, a slightly elevated temperature. But in the past few months in Brazil, it has been linked with something far worse: <a href="http://www.cdc.gov/mmwr/volumes/65/wr/mm6503e2.htm">microcephaly</a> (an abnormally small brain and head) in newborn babies. In adults an increased incidence of a rare neurological disorder called <a href="http://www.nytimes.com/2016/01/22/world/americas/zika-virus-may-be-linked-to-surge-in-rare-syndrome-in-brazil.html?_r=0">Guillan-Barre syndrome</a> has also been linked with Zika infection. This is associated with muscles weakness, paralysis and <a href="http://www.cbsnews.com/news/zika-virus-guillain-barre-syndrome-paralysis/">can be fatal</a>. Zika is anything but harmless.</p>
<p>The World Health Organisation (WHO) has declared <a href="http://www.who.int/emergencies/zika-virus/en/">Zika a global emergency</a> and predicted up to <a href="http://www.who.int/topics/zika/en/">4m Zika infections</a> in the Americas alone in 2016. Infection rates of Zika in Brazil have skyrocketed and so too has the incidence of microcephaly. Microcephaly rates in Brazil were about five cases per 100,000 live births before the Zika outbreak, but in the past six to nine months this has reached <a href="http://www.cdc.gov/mmwr/volumes/65/wr/mm6503e2.htm">200 per 100,000</a>. Microcephaly can lead to a wide range of disabilities which includes learning problems, physical problems, such as difficulties with balance and coordination, hearing and visual problems, and epilepsy.</p>
<p>The first Zika virus pregnancy case has now been <a href="http://www.bbc.co.uk/news/world-europe-35490524">confirmed in Europe</a>.</p>
<h2>Zika’s family</h2>
<p>Zika is from the flavivirus family, a group of viruses that cause yellow fever, Nile fever and dengue fever. Some of these viruses cause encephalitis, inflammation of the brain in adults, and can be life threatening. </p>
<p>We already know that some viral infections during pregnancy can cause birth defects. Perhaps the best example is German measles (rubella), which in early pregnancy can cause damage to the heart, ears and brain.</p>
<p>We know that flaviviruses related to Zika cause <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4581091/">microcephaly in newborn animals</a> following an infection during pregnancy. What is frightening is the huge increase in numbers of microcephaly cases in Brazil since the Zika outbreak. There is a strong correlation between the spread of Zika in Brazil and the <a href="http://www.cdc.gov/mmwr/volumes/65/wr/mm6503e2.htm">growing number of babies born with microcephaly</a>. </p>
<p>While this does not prove that the Zika virus is the direct cause of the microcephaly, genetic material from the virus has been detected in both mothers and in their amniotic fluid (a pregnant woman’s “waters”), indicating Zika has the potential to <a href="http://onlinelibrary.wiley.com/doi/10.1002/uog.15831/abstract;jsessionid=FB004D96989AC9954386E8DA15E07BED.f04t04">infect an unborn baby while in the womb</a>.</p>
<p>Given that other members of this virus family cause microcephaly in newborn animals, there is good reason to believe that <a href="http://www.cdc.gov/mmwr/volumes/65/wr/mm6503e2.htm">microcephaly and the Zika virus epidemic</a> are <a href="http://www.sciencedirect.com/science/article/pii/S1286457916000083">linked</a>.</p>
<h2>How could Zika virus cause microcephaly?</h2>
<p>Microcephaly is rare in humans. In some cases it’s caused by chromosomal abnormalities (such as Down syndrome). It can also be caused by viral infections, for example, if the mother has German measles or chickenpox while pregnant. In other instances, microcephaly <a href="http://www.medicinenet.com/microcephaly/article.htm">can occur</a> if the foetus is exposed to alcohol, drugs or certain toxic chemicals in the womb.</p>
<p>Of course, the simultaneous increase in the rate of Zika infections and the rate of microcephaly could be coincidental. Yet scientists know that there is a strong association between the Zika virus and microcephaly and there is the evidence of Zika transmission between mother and foetus. </p>
<p>However, to definitively prove that Zika virus causes microcephaly requires several more pieces of information. This includes determining if the affected children have other developmental problems which could associate the microcephaly with a genetic or chromosonal disorder, and monitoring women throughout their pregnancy to determine when the damage to the foetus is caused, as well as ruling out other causes. </p>
<p>Researchers will also need to carry out “case-control” studies that look at babies born with microcephaly in a Zika virus affected area (the “cases”) and compares them with children that don’t have microcephaly from the same area (the “controls”). Presence of the Zika virus will be determined in each of the groups. If the children with microcephaly all have the Zika virus but the unaffected children don’t, then this will suggest Zika virus does cause microcephaly. Sadly, this will take time.</p><img src="https://counter.theconversation.com/content/53716/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Neil Vargesson receives or has received funding for his research group from the Royal Society, Wellcome Trust, Imperial College London, University of Aberdeen. </span></em></p><p class="fine-print"><em><span>Lavinia Faccini receives funding from Brazilian National Research and Technology Council (CNPQ - Conselho Nacional de Pesquisa e Desenvolvimento Tecnológico). </span></em></p>Zika virus and microcephaly are firmly linked, but scientists are still trying to prove that it has caused the condition.Neil Vargesson, Senior Lecturer in Developmental Biology, University of AberdeenLavinia Faccini, Universidade Federal do Rio Grande do Sul (UFRGS)Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/540492016-02-05T03:11:44Z2016-02-05T03:11:44ZExplainer: what is microcephaly and what is its relationship to Zika virus?<p>This week the <a href="http://www.who.int/mediacentre/news/statements/2016/emergency-committee-zika-microcephaly/en/">World Health Organisation</a> declared Zika virus a public health emergency of international concern. </p>
<p>Despite high rates of infection, the outbreak would not have been particularly alarming – since the infection is usually asymptomatic (80% of cases) or mild and self-limiting – had it not been for the sudden and (apparently associated) <a href="http://www.cdc.gov/zika/hc-providers/qa-pediatrician.html">increase</a> in numbers of infants born with microcephaly.</p>
<h2>What is microcephaly?</h2>
<p>Microcephaly is a condition in which the infant’s head is smaller than “normal” for the infant’s age and gender, because of delayed or arrested brain growth. There is no universally agreed definition. Most authorities suggest it should be defined by a head circumference of two – but some say three – standard deviations or more below the average. </p>
<p>It is often first diagnosed by ultrasound examination during pregnancy. The incidence of microcephaly – in the absence of Zika virus infection – is difficult to determine. </p>
<p>Apart from the lack of an agreed definition or definitive diagnostic test, there is probably significant <a href="http://www.nature.com/news/zika-virus-brazil-s-surge-in-small-headed-babies-questioned-by-report-1.19259">under-reporting</a> of the condition. State-based surveillance in the United States – where Zika virus is not endemic – <a href="http://www.nbdpn.org/docs/DataDirectory2013_NBDPN_AR.pdf">suggests it occurs</a> in between two and 12 infants per 10,000 live births. Rates vary from 0.5 to 19 in 10,000 live births in different states. </p>
<p>If the incidence were similar in Brazil, where about three million infants are born each year, this would represent 600-3,600 cases a year. This is more than estimates based on <a href="http://www.cdc.gov/mmwr/volumes/65/wr/mm6503e2.htm">recent review of birth certificates</a> – approximately 0.5 per 10,000 live births. </p>
<p>Some of the <a href="http://www.nature.com/news/zika-virus-brazil-s-surge-in-small-headed-babies-questioned-by-report-1.19259">approximately 4,000 cases</a> reported in Brazil during 2015 may have been due to increased awareness and reporting – although there appears to have been a real increase also.</p>
<p>Microcephaly <a href="http://www.cdc.gov/ncbddd/birthdefects/microcephaly.html">is often associated with</a> other developmental abnormalities and with varying degrees of intellectual and developmental delay, seizures, and visual and hearing loss. In severe cases it can be life-threatening.</p>
<h2>Causes</h2>
<p>There are many recognised causes of microcephaly including a number of <a href="http://www.cdc.gov/ncbddd/birthdefects/microcephaly.html">other infections</a> in pregnant women. These include rubella, cytomegalovirus (a common virus that causes asymptomatic infection or a mild glandular fever-like illness in otherwise healthy people and severe disease in people with severe immune suppression such as AIDS), herpes simplex virus infections, syphilis and toxoplasmosis (a parasitic disease). </p>
<p>Chikungunya, a virus spread by the same mosquito responsible for spreading Zika (the Aedes aegypti, or yellow fever mosquito), <a href="http://www.ncbi.nlm.nih.gov/pubmed/25033077">has also been shown</a> to cause brain damage in infants of women infected during pregnancy in a naïve population (one without previous exposure to the virus).</p>
<p>Noninfective causes of microcephaly <a href="http://www.cdc.gov/ncbddd/birthdefects/microcephaly.html">include</a> a variety of genetic disorders, maternal exposure to drugs, alcohol, chemical toxins and radiation and severe malnutrition.</p>
<h2>Is Zika to blame?</h2>
<p>Although Zika virus has not yet been definitively proven to be the cause of the increased numbers of infants with microcephaly in Brazil, there is strong circumstantial and epidemiological evidence that it is, at least partly, responsible. </p>
<p>Many of the mothers of affected babies in Brazil reported an illness consistent with Zika virus infection in early pregnancy. However, this was often mistaken for dengue and not confirmed by laboratory tests. </p>
<p>The <a href="http://www.paho.org/hq/index.php?option=com_content&view=article&id=11623%3Apaho-directors-statement-on-zika-virus-in-the-americas-at-the-138th-who-executive-board&Itemid=135&lang=en">peak incidence</a> of microcephaly occurred in the same geographic region (northeastern Brazil) about a year after an outbreak of dengue-like illness, with fever and rash, started. Six months later Zika virus was identified as the cause.</p>
<p>There have been <a href="http://www.eurosurveillance.org/ViewArticle.aspx?ArticleId=20751">several reports of detection</a> of Zika virus genetic material (nucleic acid) in amniotic fluid, placentas, tissues of infants who have died with microcephaly and in live-born infants, with or without microcephaly, of mothers who have had Zika virus infection during pregnancy. It is highly likely that maternal Zika virus infection can damage the developing foetal brain. But the level of risk is unknown.</p>
<p>The other major uncertainly about Zika virus infection and microcephaly is the level of risk at different stages of pregnancy. Because the infection is so frequently asymptomatic or easily mistaken for other viral infections, the number of pregnant women infected and the stage of pregnancy at which infections occur are unknown.</p>
<p>For most intrauterine (within the uterus) infections that cause foetal damage (such as rubella or cytomegalovirus, for which these risks are well-known), the risk of the foetus being infected from the mother is relatively low in early pregnancy and increases with increasing gestation. </p>
<p>However, if foetal infection does, in fact, occur early in pregnancy, the foetus is more likely to be severely affected than if it occurs in the later stages of pregnancy. This is yet to be determined for Zika virus infection.</p>
<p>Hopefully, studies and enhanced surveillance of Zika virus infection and birth defects will provide answers to these questions. These are underway in Brazil.</p>
<p>In the meantime, while overall rates of Zika virus remain high, pregnant women are being advised to defer travel to Zika-affected countries if possible. Those who live there are advised to defer pregnancy or take extra precautions to avoid mosquito bites.</p><img src="https://counter.theconversation.com/content/54049/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Lyn Gilbert 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>Despite high rates of infection, the Zika outbreak would not have been particularly alarming had it not been for the sudden and – apparently associated – increase in the numbers of infants born with microcephaly.Lyn Gilbert, Clinical Professor in Medicine and Infectious Diseases, University of SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/537052016-02-04T14:28:01Z2016-02-04T14:28:01ZZika: what Brazil is doing to tackle the virus<p>The <a href="http://www.who.int/dg/speeches/2016/zika-situation/en/">“explosive” spread</a> of the Zika virus has prompted health officials to predict <a href="https://www.youtube.com/watch?v=s20MXMwRGXw">up to 4m cases</a> this year and 26 countries and territories <a href="http://www.paho.org/hq/index.php?option=com_content&view=article&id=11644%3Apaho-director-to-brief-ministers-of-health-on-microcephalyzika-in-the-americas&Itemid=1926&lang=en">have already been affected</a> in the Americas. Brazil has been particularly hit by Zika – and microcephaly, the condition that causes smaller heads in newborns that is being linked to the virus. </p>
<p>Zika is a global health problem and action to counter the threat needs to reflect this – but Brazil is key to understanding the nature of the virus and possible solutions to it. In the next few weeks the tendency will be to demand decisive leadership internationally – as well as a greater involvement of the world’s most powerful nations. But tackling Zika will ultimately come down to learning from what is happening on the ground – not around the tables of Geneva or New York. </p>
<p>The first case of this Zika virus outbreak was reported in Brazil in May 2015. Since then, an estimated 1.5m people have been infected. Healthcare officials have also reported a 20-fold increase in incidence of microcephaly. As of <a href="http://portalsaude.saude.gov.br/images/pdf/2016/fevereiro/03/COES-Microcefalias---Informe-Epidemiol--gico-11---SE-04-2016---02FEV2016---18h51-VDP.pdf">January 30</a>, 404 cases of microcephaly had been linked to an infection-related cause, with Zika virus confirmed to be present in 17 cases. A further 3,670 cases are still under investigation.</p>
<p>Brazilian health authorities face an uphill struggle. One of the difficulties is the tropical weather in which mosquitoes thrive – including the rainy season that is expected to last until April. Another difficulty is poverty and Brazil’s <a href="http://www.who.int/bulletin/volumes/86/4/08-030408/en/">working but fragile</a> health system.</p>
<p>The <em>Aedes aegypti</em> mosquito does not discriminate between rich and poor, but it reproduces in societies where poverty is endemic, where there is no reliable access to water and families use tanks and makeshift receptacles, where sanitation is inadequate or non-existent, and where rainwater and sewage run or accumulate in the open air. </p>
<p>The mosquito spreads havoc in countries where health systems are underfunded and unable to reach communities in the deprived areas of sprawling cities; where illiteracy is high and false rumours spread like wildfire; and where the efforts of health workers are stifled by corruption, bureaucracy and political point-scoring. </p>
<p>Zika is a health problem, but it is also a political one. It’s a problem of inequality, but one that will end up affecting everyone, including the wealthy. Mosquitoes may not care about politics, but politics certainly affects mosquitoes.</p>
<h2>Communities on the frontline</h2>
<p>While Brazil showcases some of the underlying social, economic and political conditions that have allowed this outbreak to become such an urgent problem, this country is also taking steps in the right direction. These should not be dismissed as international actors step in.</p>
<p>In places like Pernambuco and Paraíba (two states that are among the poorest and most heavily affected by Zika), professionals from Brazil’s Unified Health System (SUS) are working alongside the military and community health agents who give advice and collect data in remote areas and hard-to-reach favelas. The work of these community workers is essential: mosquito control is more than simply fumigation “from above” and in order to be sustainable it requires persistent work on the ground. </p>
<p>In institutions such as the <a href="http://portal.fiocruz.br/en/content/home-ingl%C3%AAs">Fundação Oswaldo Cruz</a>, cutting-edge, publicly-funded research into Zika and other neglected tropical diseases is underway. Civil society has mobilised in “Sábados de Faxina” (Cleaning-up Saturdays) and even “anti-Zika” carnival parades. This is happening amid <a href="https://www.abrasco.org.br/site/2016/02/carta-de-alerta-da-abrasco-cidades-saudaveis-e-sustentaveis-este-e-o-desafio-urgente/">calls</a> for a greater emphasis on improving sanitation as a long-term solution for Zika and other diseases affecting Brazil.</p>
<p>Despite the contested political terrain and the difficult circumstances, Brazil is showing how health workers, community representatives, researchers, civilian and military leaders can collaborate.</p>
<p>Brazil certainly needs the assistance of international partners, as is demonstrated by president Dilma Rousseff’s <a href="http://blog.planalto.gov.br/dilma-e-obama-acertam-cooperacao-para-criar-vacina-contra-o-zika-virus/">phone call to Barack Obama</a> on January 29, in which she sought to further Brazil-US cooperation in vaccine development. But it would be a mistake to see Brazil as a helpless victim, needing to be saved by outside intervention.</p>
<h2>Everyday emergencies</h2>
<p>There is much to learn from Brazil. First, considering the complex political, social and economic context of this country allows us to understand more clearly what the problem is. While the world is only now beginning to see Zika as an <a href="http://www.who.int/mediacentre/news/statements/2016/emergency-committee-zika-microcephaly/en/">emergency</a>, the conditions that have enabled the spread of the virus and hindered response are “everyday emergencies” for millions of Brazilians.</p>
<p>The second is that addressing the problem of Zika requires a long-term effort that goes beyond crisis management – and that should not stop at mosquito control and vaccine development. These responses will certainly be important, but a sustainable solution also requires addressing the social and economic determinants of health, improving sanitation and housing infrastructure, and involving civil society in the definition and implementation of policies. </p>
<p>Brazil has taken some important steps in this direction, and international actors should support this agenda rather than imposing their own.</p><img src="https://counter.theconversation.com/content/53705/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>João Nunes is currently working on a project funded by the Wellcome Trust, which looks at community health workers in Brazil and their role in promoting universal health coverage.</span></em></p>Brazil faces an uphill struggle with Zika – here’s what’s happening on the ground already.João Nunes, Lecturer, University of YorkLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/540422016-02-02T01:39:13Z2016-02-02T01:39:13ZZika emergency status a cause for alert, not alarm<p>Overnight, World Health Organisation Director-General Margaret Chan <a href="http://www.who.int/mediacentre/news/statements/2016/emergency-committee-zika-microcephaly/en/">declared</a> the outbreak of Zika virus a public health emergency. So what does this mean?</p>
<p>This is the fourth time the WHO has declared a state of emergency. The first was in 2009 for the H1N1 virus. The second and third were in 2014 for outbreaks of polio and Ebola. </p>
<p>Headlines declaring this news might sound alarmist but this is not the WHO’s intention. The alert is a political tool, to bring attention to people all over the world that this is an issue of concern.</p>
<p>It’s estimated there are more than four million people living in areas populated by the <a href="https://theconversation.com/does-zika-virus-pose-a-threat-to-australia-53557">Yellow Fever mosquito</a>, which is responsible for spreading the disease. We need to communicate the risks to these people. We need the global community to get on board to aid in control efforts in South America and the other areas affected by the Zika virus. </p>
<p>In particular, this is an opportunity for expertise to be shared across the globe, for research money to be directed to diagnostics and vaccine development and for an increase in international aid money required to control mosquito populations in some of the poorer affected countries. </p>
<p>Declaring Zika virus a public health emergency has happened relatively early in the outbreak compared to the comparable declaration for Ebola virus. But this simply reflects the acknowledged need by the world community to deal with these emergencies more quickly.</p>
<p>The emergency alert is also a call to arms to focus on research in this area, particularly to establish a causal link between the Zika virus and the reported subsequent birth defects, especially microcephaly (reduced head size and brain damage).</p>
<p>The WHO’s briefing overnight made clear that the emergency of international concern is not for Zika itself, but for the cluster of microcephaly cases and its suspected link to the Zika virus. </p>
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<p>As the WHO pointed out, Zika itself is not a clinically serious condition.</p>
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<p>The US has added Zika virus to its research agenda. The affected countries within the <a href="http://www.glopid-r.org/">Global Research Collaboration for Infectious Disease Preparedness</a>, a body of infectious disease experts and funders, are meeting this evening to discuss what resources can be diverted to help in diagnostic and vaccine development.</p>
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<blockquote>
<p>Read more: <a href="https://theconversation.com/does-zika-virus-pose-a-threat-to-australia-53557">Does Zika pose a threat to Australia?</a></p>
<p><a href="https://theconversation.com/love-in-the-time-of-zika-53866">Love in the time of Zika</a></p>
</blockquote>
<hr><img src="https://counter.theconversation.com/content/54042/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Grant Hill-Cawthorne 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>Overnight, World Health Organisation Director-General Margaret Chan declared the outbreak of Zika virus a public health emergency. So what does this mean?Grant Hill-Cawthorne, Lecturer in Communicable Disease Epidemiology, University of SydneyLicensed as Creative Commons – attribution, no derivatives.