tag:theconversation.com,2011:/ca-fr/topics/bats-and-coronavirus-81916/articlesBats and coronavirus – La Conversation2021-02-04T18:10:15Ztag:theconversation.com,2011:article/1544912021-02-04T18:10:15Z2021-02-04T18:10:15ZIn 2010, a virus similar to SARS-CoV-2 was already present in Cambodia<figure><img src="https://images.theconversation.com/files/382238/original/file-20210203-23-cnbn7h.jpg?ixlib=rb-1.1.0&rect=0%2C192%2C4288%2C2541&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A swarm of bats flies out of a cave near Phnom Sampeau, Cambodia.</span> <span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/Category:Phnom_Sampeau#/media/File:Nowhere_near_the_peak_now_(14452935885).jpg">S. Shankar/Wikipedia</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>In November and December 2010, UNESCO and Cambodian authorities invited researchers from the <em>Muséum National d'Histoire Naturelle</em> in Paris to explore several sites in northern Cambodia. The goal was to study the biodiversity of bats near the <a href="https://whc.unesco.org/en/list/1224/">Temple of Preah Vihear</a>, and a large number of bats species were caught during this survey, including eight types of horseshoe bat (genus <em>Rhinolophus</em>). They’re of great interest for virologists, as they are the reservoir of all Sarbecoviruses, the group of coronaviruses that includes SARS-CoV and SARS-CoV-2, respectively responsible for the <a href="https://doi.org/10.1515/mammalia-2020-0044">SARS epidemic in 2002-2004 and the current Covid-19 pandemic</a>.</p>
<p>In 2020, 10 years after the expedition, the samples stored in a freezer at -80°C were taken out and tested by the Institut Pasteur of Cambodia (IPC) to look for Sarbecoviruses. A PCR test showed two positive results and a full sequencing of their genome started. Two variants of a virus close to SARS-CoV-2 were discovered in two bats of the species <em>Rhinolophus shameli</em> we captured in 2010 in a cave in the province of Steung Treng.</p>
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<img alt="" src="https://images.theconversation.com/files/381759/original/file-20210201-17-164zxrj.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/381759/original/file-20210201-17-164zxrj.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/381759/original/file-20210201-17-164zxrj.PNG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/381759/original/file-20210201-17-164zxrj.PNG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/381759/original/file-20210201-17-164zxrj.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/381759/original/file-20210201-17-164zxrj.PNG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/381759/original/file-20210201-17-164zxrj.PNG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A <em>Rhinolophus shameli</em> bat, the entrance to the cave where a large colony of this species nested, and the forest clearing near the capture site.</span>
<span class="attribution"><span class="source">Alexandre Hassanin</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The results of this research are freely available on the <a href="https://www.biorxiv.org/content/10.1101/2021.01.26.428212v1">bioRxiv website</a> and pending peer review. (This practice is now widely used to rapidly transfer new knowledge about the Covid-19 pandemic.)</p>
<h2>SARS-CoV-2-like viruses are present in bats in the Yunnan province of China and in mainland Southeast Asia</h2>
<p>The discovery is important because the virus is the first found outside China that is close to SARS-CoV-2 – of the 29,913 <a href="https://en.wikipedia.org/wiki/Sequence_alignment">aligned bases</a> in the two viruses’ genomes, 93% are identical. All those previously described were detected in animals collected in China, including two viruses found in two species of <em>Rhinolophus</em> bats in southern China, and two more divergent viruses (90% and 85%) found in pangolins seized by Chinese customs in Guangdong and Guangxi provinces.</p>
<p>The new virus from Cambodia was detected in a bat species endemic to Southeast Asia that does not extend beyond Yunnan, where the two previous bat SARS-CoV-2-like viruses were found.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/382623/original/file-20210204-20-1gel4or.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/382623/original/file-20210204-20-1gel4or.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=437&fit=crop&dpr=1 600w, https://images.theconversation.com/files/382623/original/file-20210204-20-1gel4or.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=437&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/382623/original/file-20210204-20-1gel4or.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=437&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/382623/original/file-20210204-20-1gel4or.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=549&fit=crop&dpr=1 754w, https://images.theconversation.com/files/382623/original/file-20210204-20-1gel4or.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=549&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/382623/original/file-20210204-20-1gel4or.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=549&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Geographical distribution of the three bat species in which viruses close to SARS-CoV-2 have been sequenced. The colored dots indicate the localities of origin of the viruses RaTG13 (blue), RmYN02 (green), RshSTT182 and RshSTT200 (red).</span>
<span class="attribution"><span class="source">Alexandre Hassanin, iucnredlist.org</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The direct implication is that viruses similar to SARS-CoV-2 have been <a href="https://doi.org/10.1038/s41564-020-0771-4">circulating for several decades</a>, as revealed by molecular dating, throughout Southeast Asia and Yunnan, and that different species of bats could have exchanged these viruses in the caves they inhabit.</p>
<p>Chinese researchers have been searching for Sarbecoviruses throughout the country for about 15 years. They found more than 100 SARS-CoV-like viruses but only two related to SARS-CoV-2. The new data thus validates the hypothesis that SARS-CoV-2-like viruses are present mostly in Southeast Asia, while SARS-CoV-like viruses are dominant in China.</p>
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<img alt="" src="https://images.theconversation.com/files/382624/original/file-20210204-14-1lt2ooe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/382624/original/file-20210204-14-1lt2ooe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=408&fit=crop&dpr=1 600w, https://images.theconversation.com/files/382624/original/file-20210204-14-1lt2ooe.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=408&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/382624/original/file-20210204-14-1lt2ooe.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=408&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/382624/original/file-20210204-14-1lt2ooe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=513&fit=crop&dpr=1 754w, https://images.theconversation.com/files/382624/original/file-20210204-14-1lt2ooe.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=513&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/382624/original/file-20210204-14-1lt2ooe.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=513&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Number of Covid-19 patients per million inhabitants (in blue) and deaths per million inhabitants (in red) for the different countries of Southeast Asia.</span>
<span class="attribution"><span class="source">Alexandre Hassanin, worldometers.info/coronavirus</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The data in the figure above indirectly support the hypothesis that the SARS-CoV-2 group actually originated in mainland Southeast Asia. Indeed, human populations in Cambodia, Laos, Thailand and Vietnam appear to be much less affected by the Covid-19 pandemic than other countries in the region, such as Bangladesh, Myanmar, Malaysia, the Philippines and Indonesia. This suggests that the populations of these four countries may be benefiting from a level of herd immunity to Sarbecoviruses.</p>
<h2>Pangolins contaminated by bats in Southeast Asia</h2>
<p>Apart from bats, the Malayan pangolin (<em>Manis javanica</em>) is the only wild animal in which SARS-CoV-2-like viruses have been found. The problem is that these discoveries were made in a rather special context, that of pangolin trafficking. Several sick animals were seized by Chinese customs in Guangxi province in 2017-2018 and in Guangdong province in 2019.</p>
<p>Even if the viruses sequenced in pangolins are not that close to SARS-CoV-2 (one was 85% identical and the other 90%), they indicate that at least two Sarbecoviruses could have been imported into China well before the Covid-19 epidemic. Indeed, it has been shown that pangolins from Southeast Asian countries have contaminated each other <a href="https://www.degruyter.com/view/journals/mamm/ahead-of-print/article-10.1515-mammalia-2020-0044/article-10.1515-mammalia-2020-0044.xml">while in captivity</a> on Chinese territory.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/382628/original/file-20210204-16-1u8zyoz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/382628/original/file-20210204-16-1u8zyoz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/382628/original/file-20210204-16-1u8zyoz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/382628/original/file-20210204-16-1u8zyoz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/382628/original/file-20210204-16-1u8zyoz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/382628/original/file-20210204-16-1u8zyoz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/382628/original/file-20210204-16-1u8zyoz.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">The pangolin, one of the most poached animals in the world, could have served as an intermediate host in the transmission of SARS-CoV-2 to humans.</span>
<span class="attribution"><span class="source">Wahyudi/AFP</span></span>
</figcaption>
</figure>
<p>The question remains on how the pangolins became infected initially. Could it have been in their natural Southeast Asian environment, before being captured? The discovery of a new virus close to SARS-CoV-2 in bats in Cambodia supports this hypothesis, as <em>Rhinolophus</em> bats and pangolins can meet, at least occasionally, in <a href="https://www.degruyter.com/view/journals/mamm/ahead-of-print/article-10.1515-mammalia-2020-0044/article-10.1515-mammalia-2020-0044.xml">caves in Southeast Asia</a>. This strengthens the hypothesis that <a href="https://theconversation.com/coronavirus-origins-genome-analysis-suggests-two-viruses-may-have-combined-134059">pangolin trafficking</a> is responsible for multiple exports of SARS-CoV-2-like viruses to China.</p>
<h2>The “snowballing” effect of breeding small carnivores</h2>
<p>In 2002-2004, <a href="https://www.degruyter.com/view/journals/mamm/ahead-of-print/article-10.1515-mammalia-2020-0044/article-10.1515-mammalia-2020-0044.xml">several small carnivores</a> kept in cages in Chinese markets or restaurants were found positive for SARS-CoV, such as the masked palm civet, the <a href="https://en.wikipedia.org/wiki/Raccoon_dog">raccoon dog</a> and the Chinese ferret-badger.</p>
<p>These small carnivores are solitary and nocturnal mammals – just like pangolins. In the wild, the occasional contamination of an individual of these species by a bat Sarbecovirus has very little chance of causing an epidemic. However, an infected individual placed in an intensive breeding facility can lead to a rapid and uncontrollable evolution of this type of virus.</p>
<p>In 2020, <a href="https://www.theguardian.com/world/2020/oct/11/utah-10000-minks-dead-from-coronavirus">American minks</a> bred for their fur were contaminated with the SARS-CoV-2 virus from humans in Europe and the United States. In November 2020, <a href="https://www.theguardian.com/environment/2020/nov/04/denmark-announces-cull-of-15-million-mink-over-covid-mutation-fears">millions of mink in Denmark were culled</a> after they became infected with Covid-19 and in turn passed a mutated form back to humans.</p>
<p>The Covid-19 crisis taught the world that keeping immense numbers of small carnivores in captivity is a <a href="https://science.sciencemag.org/content/371/6525/172">major health risk</a>: viruses can spread and evolve rapidly in breeding facilities, potentially producing more contaminating or more dangerous variants. As pangolins and small carnivore species were frequently stored and sold together in wet markets, a “snowballing effect” due to interspecies viral transmission could be the last step in starting the human Covid-19 pandemic.</p>
<p>This scenario is mot likely as nearly <a href="https://www.nationalgeographic.com/magazine/2019/06/pangolins-poached-for-scales-used-in-chinese-medicine/">1 million pangolins have been trafficked in the past decade</a> and millions of small carnivores are <a href="https://reporterre.net/Mounting-evidence-suggests-mink-farms-in-China-could-be-the-cradle-of-Covid-19-22020">bred in fur farms in China</a>.</p>
<p>To test this hypothesis and understand why epidemics are emerging in China and not elsewhere, it would be interesting to look for possible infection by Sarbecoviruses in samples from American minks and raccoon dogs bred for their fur in China. These samples exist, they have been collected in the last two decades to study the <a href="https://doi.org/10.1016/j.vetmic.2009.07.010">canine distemper virus</a> or avian flu viruses <a href="https://doi.org/10.1016/j.vetmic.2017.01.028">H5N1</a> and <a href="https://doi.org/10.1016/j.vetmic.2015.01.009">H9N2</a>.</p>
<hr>
<p><em>This article was translated from the original French by Elsa Couderc with help from DeepL.</em></p><img src="https://counter.theconversation.com/content/154491/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Alexandre Hassanin 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 bat virus discovered a decade ago in Cambodia indicates that pangolin trafficking remains a credible explanation for the origin of the Covid-19 pandemic.Alexandre Hassanin, Maître de Conférences (HDR) à Sorbonne Université, ISYEB - Institut de Systématique, Evolution, Biodiversité (CNRS, MNHN, SU, EPHE, UA), Muséum national d’histoire naturelle (MNHN)Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1439492020-08-18T14:24:54Z2020-08-18T14:24:54ZSome bats find their way around like people do: why this is useful to know<figure><img src="https://images.theconversation.com/files/351121/original/file-20200804-14-z9iltl.jpg?ixlib=rb-1.1.0&rect=20%2C59%2C743%2C469&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">An Egyptian Fruit Bat in flight.</span> <span class="attribution"><span class="source">Sherri and Brock Fenton</span></span></figcaption></figure><p>Flight makes bats unique among mammals and confers on them the potential to cover large distances. And yet, for most of the approximately 1,400 or so species of bats, we have little information about the extent and details of their travels. </p>
<p>Two <a href="https://science.sciencemag.org/content/369/6500/188">papers</a> <a href="https://science.sciencemag.org/content/369/6500/194">published</a> in <em>Science</em> in July 2020 have added to our understanding of how bats – specifically Egyptian Fruit bats – travel. Each paper was the work of a team of Israeli researchers who, using several kinds of technology including GPS tags, documented the movements of Egyptian Fruit bats from Israel’s Hula Valley. They showed that these bats, which weigh about 150 grams, have home ranges exceeding 60 km². They also discovered that, once they could fly, young bats took about 70 days to use home ranges as large as those of adults.</p>
<p>As an expert on bats who has published extensive research and <a href="https://books.google.co.za/books/about/Bats.html?id=4Ad-BwAAQBAJ&redir_esc=y">books</a> on these animals, I provided <a href="https://science.sciencemag.org/content/369/6500/142?rss=1">a commentary</a> in Science on these new findings. I pointed out that there was more to the papers than the extent to which these bats covered ground. Rather, the data reveal that bats used a <a href="https://www.sciencedirect.com/topics/neuroscience/cognitive-map">cognitive map</a> to navigate their home ranges. </p>
<p>This is a detailed inner ‘map’ in which information about our geographical and physical world is stored, analysed and altered as necessary. Here you might think of your own ‘home range’: how you move about in it to make the best use of your time, whether you are looking for food or to meet friends. Your cognitive map makes this second nature.</p>
<p>This important discovery demonstrates that such maps are not the exclusive domain of humans and a few other species. Documenting animals’ use of cognitive maps allows researchers to unravel the brain and sensory processes involved in navigation. It could also have positive implications for conservation, helping us to better understand the areas where these bats may travel and roost.</p>
<p>Another side to knowing about the distances covered by bats relates to public health and their association with some viral diseases that affect people. <a href="https://www.who.int/news-room/fact-sheets/detail/ebola-virus-disease">Ebola</a> is a grim example; <a href="http://scholar.google.co.za/scholar_url?url=https://www.facetsjournal.com/doi/full/10.1139/facets-2020-0028&hl=en&sa=X&scisig=AAGBfm1W57gy_SHL_zZ4zX43PQs9Vn7Bcw&nossl=1&oi=scholarr">COVID-19</a> another. <a href="https://www.idse.net/Covid19/Article/05-20/Why-Are-Bats-the-Perfect-Coronavirus-Reservoir/58486">Bats are reservoirs for SARS CoV-2</a>, which causes COVID-19. We do not yet know how this virus moves from bats to people. Learning more about how bats operate can only benefit us. </p>
<h2>Diverse and quite different</h2>
<p>Bats are diverse, distinctive, and quite different from other mammals. For example, they bear large young (about 25% of the mother’s body mass), and many live a long time – about 20 years in the wild. Most bats orient by biosonar or echolocation, allowing them to ‘see’ in the dark. </p>
<p>Africa has <a href="https://www.awf.org/wildlife-conservation/bat#:%7E:text=Over%20200%20species%20of%20African,percent%20of%20the%20world's%20bats.&text=Varies%20by%20species%20%E2%80%94%20the%20largest,840%20mm%20(33%20inches).">more than 200 species</a> of bats, ranging in body mass from about 3g to around 300g. African bats play different roles in ecosystems, but most eat mainly insects and other arthropods. Some African species eat fruit and disperse seeds, while others visit flowers and are important as pollinators. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/351122/original/file-20200804-20-1s7ttzk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/351122/original/file-20200804-20-1s7ttzk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=273&fit=crop&dpr=1 600w, https://images.theconversation.com/files/351122/original/file-20200804-20-1s7ttzk.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=273&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/351122/original/file-20200804-20-1s7ttzk.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=273&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/351122/original/file-20200804-20-1s7ttzk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=343&fit=crop&dpr=1 754w, https://images.theconversation.com/files/351122/original/file-20200804-20-1s7ttzk.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=343&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/351122/original/file-20200804-20-1s7ttzk.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=343&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A bushveld bat emerging from a cave.</span>
<span class="attribution"><span class="source">Sherri and Brock Fenton</span></span>
</figcaption>
</figure>
<p>As their name implies, the Egyptian Fruit bat that was the subject of these two studies occurs mainly in Africa, from Cape Town northwards, and into some areas in the Middle East. They eat fruit and are common zoo animals, well known to many people well beyond Africa. </p>
<p>Bats are mainly nocturnal and their survival means having a safe place to spend the day. They roost in a wide variety of places, from underground hollows (caves and mines), to hollows in trees and in buildings. Some roost in foliage; others out in plain sight. Some roosts contain thousands of bats, but many others shelter only a few individuals. </p>
<p>In different parts of the world, banding studies – in which bands are used to mark and identify the animals – have revealed that individual bats return to the same roosts year after year, over decades. One banded Brandt’s myotis returned to the same site each year for <a href="https://pubmed.ncbi.nlm.nih.gov/16339320/">over 40 years</a>. We now know that many bats use a variety of roosts and this repertoire provides appropriate shelter and access to other group members. Use of cognitive maps explains this behaviour. Detailed knowledge of their home ranges, whether places to roost or to find food, are vital to the survival of bats – whether of individuals or species. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/353047/original/file-20200816-20-1rr0j83.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/353047/original/file-20200816-20-1rr0j83.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=702&fit=crop&dpr=1 600w, https://images.theconversation.com/files/353047/original/file-20200816-20-1rr0j83.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=702&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/353047/original/file-20200816-20-1rr0j83.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=702&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/353047/original/file-20200816-20-1rr0j83.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=882&fit=crop&dpr=1 754w, https://images.theconversation.com/files/353047/original/file-20200816-20-1rr0j83.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=882&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/353047/original/file-20200816-20-1rr0j83.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=882&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">A mother epauletted fruit bat with her almost independent young. They occur widely in African savannahs.</span>
<span class="attribution"><span class="source">Sherri and Brock Fenton</span></span>
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<p>Some bats lead very social lives and being with group members can be important to them. Contact with others allows many bats to save energy; they huddle to keep warm. It can also improve their chances for reproductive success. Such detailed knowledge is central to our lives as well – and, as with bats, involves cognitive maps. We know where to find shelter, food, our friends. This new research shows that bats know the same things. </p>
<h2>Why it matters</h2>
<p>Bats’ use of cognitive maps raises interesting questions about their conservation. Bats’ small size, low reproductive output, and longevity make them vulnerable. Destruction of roosts and foraging areas puts many bats at risk. Too often, the situation is exacerbated by bats’ negative image. </p>
<p>Effective conservation plans mean protecting bats’ home ranges. Most lists of bats occurring in an area, for example a national park, indicate where species have been reported, and perhaps the locations of some roosts.</p>
<p>To effectively protect areas vital to a species, we also must know how far they range, as well as why and how they use different features and areas. Knowing that bats likely have cognitive maps makes it easier for us to appreciate the areas they cover and to plan accordingly.</p>
<p>There are possible benefits for public health, too. Almost everywhere in the world, bats coexist with people. Learning more about how they operate – for example how they <a href="https://elifesciences.org/articles/48401">neutralise viruses</a> that are potentially fatal to us – can benefit us.</p><img src="https://counter.theconversation.com/content/143949/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Melville (Brock) Fenton 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>This important discovery demonstrates that cognitive maps are not the exclusive domain of humans and a few other species.Melville (Brock) Fenton, Emeritus Professor of Biology, Western UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1433522020-08-11T20:08:47Z2020-08-11T20:08:47ZCoronavirus misinformation is a global issue, but which myth you fall for likely depends on where you live<p>In February, major social media platforms attended a <a href="https://www.reuters.com/article/us-health-coronavirus-technology/white-house-to-meet-large-tech-companies-to-discuss-ways-to-control-coronavirus-outbreak-idUSKBN20X3CH">meeting hosted by the World Health Organisation</a> to address coronavirus misinformation. The aim was to catalyse the fight against what the United Nations has called an “<a href="https://www.un.org/en/un-coronavirus-communications-team/un-tackling-%E2%80%98infodemic%E2%80%99-misinformation-and-cybercrime-covid-19">infodemic</a>”. </p>
<p>Usually, misinformation is focused on specific regions and topics. But COVID-19 is different. For what seems like the first time, both misinformation and fact-checking behaviours are coordinated around a common set of narratives the world over. </p>
<p>In our <a href="https://esoc.princeton.edu/publications/esoc-covid-19-disinformation-tracking-report">research</a>, we identified the key trends in both coronavirus misinformation and fact-checking efforts. Using Google’s <a href="https://toolbox.google.com/factcheck/explorer">Fact Check Explorer computing interface</a> we tracked fact-check posts from January to July – with the first checks appearing as early as January 22. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/352176/original/file-20200811-23-8q2s3q.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/352176/original/file-20200811-23-8q2s3q.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/352176/original/file-20200811-23-8q2s3q.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/352176/original/file-20200811-23-8q2s3q.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/352176/original/file-20200811-23-8q2s3q.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/352176/original/file-20200811-23-8q2s3q.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/352176/original/file-20200811-23-8q2s3q.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/352176/original/file-20200811-23-8q2s3q.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Google’s Fact Check Explorer database is connected with a range of fact-checkers, most of which are part of the Poynter Institute’s International Fact-Checking Network.</span>
<span class="attribution"><span class="source">Screenshot</span></span>
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<h2>A uniform rate of growth</h2>
<p>Our research found the volume of fact-checks on coronavirus misinformation increased steadily in the early stages of the virus’s spread (January and February) and then increased sharply in March and April – when the virus <a href="https://www.nature.com/articles/d41586-020-00758-2">started to spread globally</a>.</p>
<p>Interestingly, we found the same pattern of gradual and then sudden increase even after dividing fact-checks into Spanish, Hindi, Indonesian and Portuguese. </p>
<p>Thus, misinformation and subsequent fact-checking efforts trended in a similar way right across the globe. This is a unique feature of COVID-19. </p>
<p>According to our analysis, there has been no equivalent global trend for other issues such as elections, terrorism, police activity or immigration.</p>
<h2>Different nations, different misconceptions</h2>
<p>On March 16, the Empirical Studies of Conflict Project, in collaboration with Microsoft Research, <a href="https://esoc.princeton.edu/publications/esoc-covid-19-disinformation-tracking-report">began cataloguing COVID-19 misinformation</a>. </p>
<p>It did this by collating news articles with reporting by a wide range of local fact-checking networks and global groups such as Agence France-Presse and NewsGuard.</p>
<p>We analysed this data set to explore the evolution of specific COVID-19 narratives, with “<a href="https://drive.google.com/file/d/1AEE9TjqPjuUeTtZzyEAGHi5Mmu2V5P1N/view">narrative</a>” referring to the type of story a piece of misinformation pushes. </p>
<p>For instance, one misinformation narrative concerns the “origin of the virus”. This includes the false claim the virus jumped to humans as a result of <a href="https://www.theguardian.com/world/2020/jan/31/bat-soup-dodgy-cures-and-diseasology-the-spread-of-coronavirus-bunkum">someone eating</a> <a href="https://www.health.com/condition/infectious-diseases/coronavirus-bat-soup">bat soup</a>.</p>
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Read more:
<a href="https://theconversation.com/the-conversations-factcheck-granted-accreditation-by-international-fact-checking-network-at-poynter-74363">The Conversation's FactCheck granted accreditation by International Fact-Checking Network at Poynter</a>
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<p>We found the most common narrative worldwide was related to “emergency responses”. These stories reported false information about government or political responses to fighting the virus’s outbreak.</p>
<p>This may be because, unlike narratives surrounding the “nature of the virus”, it is easy to speculate on (and hard to prove) whether people in power have good or ill intent.</p>
<p>Notably, this was also the most common narrative in the US, with an early example being a <a href="https://edition.cnn.com/2020/03/14/tech/twitter-coronavirus-new-york-misinformation/index.html">false rumour</a> the New York Police Department would immediately lock down New York City. </p>
<p>What’s more, a major motivation for spreading misinformation on social media is politics. The US is a <a href="https://www.pewresearch.org/topics/political-polarization/">polarised political environment</a>, so this might help explain the trend towards political misinformation.</p>
<p>We also found China has more misinformation narratives than any other country. This may be because China is the world’s most populous country. </p>
<p>However, it’s worth noting the <a href="https://www.reuters.com/article/us-china-internet/china-launches-platform-to-stamp-out-online-rumors-idUSKCN1LF0HL">main fact-checking website</a> used by the Empirical Studies of Conflict Project for misinformation coming out of China is run by the Chinese Communist Party. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/349615/original/file-20200727-29-tdwmlm.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/349615/original/file-20200727-29-tdwmlm.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=392&fit=crop&dpr=1 600w, https://images.theconversation.com/files/349615/original/file-20200727-29-tdwmlm.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=392&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/349615/original/file-20200727-29-tdwmlm.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=392&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/349615/original/file-20200727-29-tdwmlm.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=492&fit=crop&dpr=1 754w, https://images.theconversation.com/files/349615/original/file-20200727-29-tdwmlm.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=492&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/349615/original/file-20200727-29-tdwmlm.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=492&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">This chart shows the proportion of total misinformation narratives on COVID-19 by the top ten countries between January and July, 2020.</span>
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<p>When fighting misinformation, it is important to have as wide a range of <a href="https://www.poynter.org/ifcn-fact-checkers-code-of-principles/">independent and transparent</a> fact-checkers as possible. This reduces the potential for bias.</p>
<h2>Hydroxychloroquine and other (non) ‘cures’</h2>
<p>Another set of misinformation narratives was focused on “false cures” or “false preventative measures”. This was among the most common themes in both China and Australia. </p>
<p>One example was a <a href="https://www.nytimes.com/2020/07/28/technology/virus-video-trump.html">video</a> that went viral on social media suggesting hydroxychloroquine is an effective coronavirus treatment. This is despite <a href="https://theconversation.com/hydroxychloroquine-for-covid-19-a-new-review-of-several-studies-shows-flaws-in-research-and-no-benefit-137869">experts stating</a> it is <em>not</em> a proven COVID-19 treatment, and can actually have harmful side effects.</p>
<p>Myths about the “nature of the virus” were also common. These referred to specific characteristics of the virus – such as that it can’t spread on surfaces. We know this <a href="https://www.health.gov.au/sites/default/files/documents/2020/03/coronavirus-covid-19-environmental-cleaning-and-disinfection-principles-for-health-and-residential-care-facilities.pdf">isn’t true</a>. </p>
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Read more:
<a href="https://theconversation.com/we-know-how-long-coronavirus-survives-on-surfaces-heres-what-it-means-for-handling-money-food-and-more-134671">We know how long coronavirus survives on surfaces. Here's what it means for handling money, food and more</a>
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<h2>Narratives reflect world events</h2>
<p>Our analysis found different narratives peaked at different stages of the virus’s spread. </p>
<p>Misinformation about the nature of the virus was prevalent during the outbreak’s early stages, probably spurred by an initial lack of scientific research regarding the nature of the virus. </p>
<p>In contrast, theories relating to emergency responses surfaced later and remain even now, as governments continue to <a href="https://www.theguardian.com/australia-news/audio/2020/aug/11/life-under-covid-19-lockdown-in-melbourne">implement measures</a> to fight COVID-19’s spread. </p>
<h2>A wide variety of fact-checkers</h2>
<p>We also identified greater diversity in websites fact-checking COVID-19 misinformation, compared to those investigating other topics.</p>
<p>Since January, only 25% of 6,000 fact-check posts or articles were published by the top five fact-checking websites (ranked by number of posts). In comparison, 68% of 3,000 climate change fact-checks were published by the top five websites. </p>
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<strong>
Read more:
<a href="https://theconversation.com/5-ways-to-help-stop-the-infodemic-the-increasing-misinformation-about-coronavirus-137561">5 ways to help stop the 'infodemic,' the increasing misinformation about coronavirus</a>
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<p>It seems resources previously devoted to a wide range of topics are now homing in on coronavirus misinformation. Nonetheless, it’s impossible to know the total volume of this content online.</p>
<p>For now, the best defence is for governments and online platforms to increase awareness about false claims and build on the robust fact-checking infrastructures at our disposal.</p>
<img src="https://counter.theconversation.com/content/143352/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jacob Shapiro has received funding for work relevant to this topic from the Bertelsmann Foundation and Microsoft.</span></em></p><p class="fine-print"><em><span>Jan Oledan is affiliated with the World Bank Group.</span></em></p><p class="fine-print"><em><span>Jason Weismueller and Paul Harrigan do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>When it comes to COVID-19 misinformation, not all nations are the same. Some are peddling a larger variety of myths than others - and each seems to have its own personal favourite.Jason Weismueller, Doctoral Researcher, The University of Western AustraliaJacob Shapiro, Professor of Politics and International Affairs, Princeton UniversityJan Oledan, Research Specialist, Princeton UniversityPaul Harrigan, Associate Professor of Marketing, The University of Western AustraliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1343002020-03-24T12:15:29Z2020-03-24T12:15:29ZIt’s wrong to blame bats for the coronavirus epidemic<figure><img src="https://images.theconversation.com/files/322085/original/file-20200321-22636-jhqji4.jpg?ixlib=rb-1.1.0&rect=8%2C8%2C1982%2C1416&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A small colony of Townsend's big eared bats at Lava Beds National Monument, Calif.</span> <span class="attribution"><a class="source" href="https://flic.kr/p/CCGniR">Shawn Thomas, NPS/Flickr</a></span></figcaption></figure><p>Genomic research showing that the COVID-19 coronavirus <a href="https://doi.org/10.1038/s41591-020-0820-9">likely originated in bats</a> has produced <a href="https://www.thedailybeast.com/fox-news-host-jesse-watters-claims-chinese-people-eating-raw-bats-to-blame-for-coronavirus">heavy media coverage</a> and widespread concern. There is now danger that frightened people and misguided officials will try to curb the epidemic by <a href="https://www.youtube.com/watch?v=VqfNSx8O0wg">culling</a> these remarkable creatures, even though this strategy has <a href="http://dx.doi.org/10.1007/s10393-015-1075-7">failed in the past</a>. </p>
<p>As an <a href="https://www.researchgate.net/profile/Peter_Alagona2">environmental historian</a> focusing on endangered species and biological diversity, I know that bats provide valuable services to humans and need protection. Instead of blaming bats for the coronavirus epidemic, I believe it’s important to know more about them. Here’s some background explaining why they carry so many viruses, and why these viruses only jump infrequently to humans – typically, when people hunt bats or intrude into places where bats live.</p>
<h2>The challenges of life as a bat</h2>
<p>It’s not easy being the world’s only flying mammal. Flying requires a lot of energy, so bats need to consume nutritious foods, such as fruits and insects. </p>
<p>As they forage, bats pollinate <a href="http://dx.doi.org/10.1093/aob/mcp197">around 500 plant species</a>, including mangoes, bananas, guavas and agaves (the source of tequila). Insect-eating bats may consume the equivalent of their body weight in bugs each night – including mosquitoes that carry diseases like Zika, dengue and malaria. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/322086/original/file-20200321-22610-5l8t0o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/322086/original/file-20200321-22610-5l8t0o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/322086/original/file-20200321-22610-5l8t0o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/322086/original/file-20200321-22610-5l8t0o.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/322086/original/file-20200321-22610-5l8t0o.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/322086/original/file-20200321-22610-5l8t0o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/322086/original/file-20200321-22610-5l8t0o.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/322086/original/file-20200321-22610-5l8t0o.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Grey-headed flying fox feeding on flower nectar, Queensland, Australia. Its face is covered with yellow pollen, which it will spread to other flowers.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Grey-headed_Flying_Fox_(IMG0526).jpg">Andrew Mercer/Wikipedia</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
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<p>Bats convert these foods into droppings called guano, which nourish entire ecosystems, have been harvested for centuries as <a href="https://homeguides.sfgate.com/benefits-bat-guano-fertilizer-71115.html">fertilizer</a>, and have been used to make <a href="http://dx.doi.org/10.1128/CMR.00017-06">soaps and antibiotics</a>.</p>
<p>Since fruits and insects tend to follow seasonal boom-and-bust cycles, most bats hibernate for long periods, during which their core body temperatures may fall as low as 43 degrees Fahrenheit (6 degrees Celsius). To conserve warmth, they gather in insulated places like caves, use their wings as blankets and huddle together in colonies.</p>
<p>When fruits ripen and insects hatch, bats wake up and flutter out of their roosts to forage. But now they have a different problem: Flying requires so much energy that their metabolic rates may spike as high as 34 times their resting levels, and their core body temperatures can exceed 104 degrees F. </p>
<p>To stay cool, bats have wings filled with blood vessels that radiate heat. They also lick their fur to simulate sweat and pant like dogs. And they rest during the heat of the day and forage in the cool of night, which makes their ability to navigate by <a href="https://www.britannica.com/science/echolocation">echolocation</a>, or reflected sound, handy.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/YwWGvf38TVM?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">The Congress Avenue Bridge in Austin, Texas, houses the largest urban bat colony in the world.</span></figcaption>
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<h2>Diverse and unique</h2>
<p>Humans are more closely <a href="https://research.amnh.org/paleontology/perissodactyl/node/55">related</a> to bats than we are to dogs, cows or whales. But bats seem more alien, which can make it harder for people to relate to them. </p>
<p>Bats are the most unusual of the world’s 26 <a href="https://www.ck12.org/c/life-science/classification-of-mammals/lesson/Mammal-Classification-MS-LS/">mammal orders</a>, or large groups, such as rodents and carnivores. They are the only land mammals that navigate by echolocation, and the only mammals capable of true flight. </p>
<p>Many bats are small and have rapid metabolisms, but they reproduce slowly and live long lives. That’s more typical of large animals like sharks and elephants.</p>
<p>And a bat’s internal body temperatures can fluctuate by more than 60 degrees Fahrenheit in response to external conditions. This is more typical of cold-blooded animals that take on the temperature of their surroundings, like turtles and lizards.</p>
<p>Bats carry a range of viruses that can sicken other mammals when they jump species. These include at least 200 coronaviruses, some of which cause human respiratory diseases like <a href="http://dx.doi.org/10.3201/eid1212.060401">SARS</a> and <a href="http://dx.doi.org/10.3201/eid1911.131172">MERS</a>. Bats also host several <a href="https://www.cdc.gov/vhf/virus-families/filoviridae.html">filoviruses</a>, including some that in humans manifest as deadly hemorrhagic fevers like <a href="https://doi.org/10.1038/s41564-018-0328-y">Marburg and probably even Ebola</a>.</p>
<p>Normally, these viruses remain hidden in bats’ bodies and ecosystems without harming humans. People raise the risk of transmission between species when they <a href="https://doi.org/10.1038/s41598-017-08065-z">encroach on bats’ habitats</a> or <a href="https://doi.org/10.1007/978-3-319-25220-9_12">harvest bats for medicine or food</a>. In particular, humans <a href="https://theconversation.com/re-creating-live-animal-markets-in-the-lab-lets-researchers-see-how-pathogens-like-coronavirus-jump-species-130773">pack live bats into unsanitary conditions</a> with other wild species that may serve as intermediate hosts. This is what happened at the Wuhan wet market where many experts believe <a href="https://doi.org/10.3390/v12020135">COVID-19 emerged</a>.</p>
<p>With a few exceptions, such as rabies, bats <a href="https://theconversation.com/why-dont-viruses-make-their-original-hosts-sick-5-questions-answered-131030">host their pathogens without getting sick</a>. Recent media coverage attempting to explain this riddle has focused on a 2019 study suggesting that bats carry a gene mutation, which may enable them to <a href="https://doi.org/10.1038/s41586-020-2012-7">remain healthy while harboring such viruses</a>. But while the mutation may be of interest from a public health perspective, understanding where this novel coronavirus came from requires understanding what makes a bat a bat.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/322087/original/file-20200321-22618-1on44nr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/322087/original/file-20200321-22618-1on44nr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/322087/original/file-20200321-22618-1on44nr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/322087/original/file-20200321-22618-1on44nr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/322087/original/file-20200321-22618-1on44nr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/322087/original/file-20200321-22618-1on44nr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/322087/original/file-20200321-22618-1on44nr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/322087/original/file-20200321-22618-1on44nr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The blood vessels in bats’ wings (shown: fruit bats, Northern Territory, Australia) radiate some of the heat they generate while flying.</span>
<span class="attribution"><a class="source" href="https://flic.kr/p/9UYR9M">shellac/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Why do bats carry so many diseases but seem unaffected by them? Genetic mutations that boost their immune systems may help. But a better answer is that bats are the only mammals that fly.</p>
<p>With thousands of bats crowded together licking, breathing and pooping on one another, bat caves are ideal environments for breeding and transmitting germs. But when bats fly, they generate so much internal heat that, according to many scientists, their bodies are able to fight off the germs they carry. This is known as the “<a href="http://dx.doi.org/10.3201/eid2005.130539">flight as fever hypothesis</a>.”</p>
<h2>Bats at risk</h2>
<p>Bats may not always be around to eat insect pests, pollinate fruit crops and provide fertilizer. According to the <a href="https://www.iucn.org/">International Union for the Conservation of Nature</a> and <a href="http://www.batcon.org/why-bats/bats-are/bats-are-threatened">Bat Conservation International</a>, at least 24 bat species are critically endangered, and 104 are vulnerable to extinction. For at least 224 additional bat species, scientists lack the data to know their status.</p>
<p>Overharvesting, persecution and habitat loss are the greatest threats that bats face, but they also suffer from their own novel diseases. Since it was first documented in upstate New York in 2007, the fungal pathogen <em>Pseudogymnoascus destructans</em> (Pd), which causes <a href="https://www.whitenosesyndrome.org/">white-nose syndrome</a>, has infected 13 North American bat species, including two listed as endangered.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1235582947182473216"}"></div></p>
<p>Nobody knows where Pd came from, but the fact that several bat species seem never to have encountered it before suggests that people probably introduced or spread it. The fungus thrives in cool, damp places like caves. It grows on bats while they’re hibernating, causing such irritation that they become restless, wasting precious energy during seasons when little food is available. White-nose syndrome has killed millions of bats, including <a href="http://dx.doi.org/10.1371/journal.pone.0038920">more than 90%</a> of the bats in some populations.</p>
<p>Bats are extraordinary creatures that benefit people in myriad ways, and our world would be a poorer, duller and more dangerous place without them. They need protection from the cruel treatment and wasteful exploitation that also threatens human health. </p>
<p>[<em><a href="https://theconversation.com/us/newsletters?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=upper-coronavirus-daily">Our newsletter explains what’s going on with the coronavirus pandemic. Subscribe now</a>.</em>]</p><img src="https://counter.theconversation.com/content/134300/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Peter Alagona has received funding from the National Science Foundation, Mellon Foundation, Haynes Foundation, National Oceanic and Atmospheric Administration, and the University of California. </span></em></p>The value that bats provide to humans by pollinating crops and eating insects is far greater than harm from virus transmission – which is mainly caused by human actions.Peter Alagona, Associate Professor of History, Geography and Environmental Studies, University of California, Santa BarbaraLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1307902020-02-04T13:31:30Z2020-02-04T13:31:30ZA clue to stopping coronavirus: Knowing how viruses adapt from animals to humans<figure><img src="https://images.theconversation.com/files/313184/original/file-20200202-41495-ndlo4u.jpg?ixlib=rb-1.1.0&rect=8%2C141%2C2847%2C1644&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A horseshoe bat chasing a moth. Horseshoe bats were the source of SARS. Scientists consider bats to be a possible source of coronavirus.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/greater-horseshoe-bat-rinolofidae-while-catching-a-moth-news-photo/492780961?adppopup=true">DE AGOSTINI PICTURE LIBRARY / Contributor</a></span></figcaption></figure><p>As the <a href="https://www.nytimes.com/2020/02/02/world/asia/china-coronavirus.html">novel coronavirus death toll mounts</a>, it is natural to worry. How far will this virus travel through humanity, and could another such virus arise seemingly from nowhere? </p>
<p>As <a href="https://scholar.google.com/citations?user=OH5OPd4AAAAJ&hl=en">microbial ecologists</a> who study the origins of new microbial species, we would like to give some perspective.</p>
<p>As a result of continuing deforestation, “bushmeat” hunting of wild animals and caring for our domestic animals, the novel coronavirus will certainly not be the last deadly virus from wild animals to infect <a href="https://doi.org/%2010.3201/eid1112.040789">humans</a>. Indeed, wild species of bats and primates abound in viruses closely <a href="https://doi.org/10.3390/v11030210">related to SARS</a> and <a href="https://doi.org/10.3201/eid0805.010522">HIV</a>, respectively. When humans interact with wild animal species, pathogens that are resident in those animals can spill over to humans, sometimes with deadly effects. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/313185/original/file-20200202-41516-18c8t58.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/313185/original/file-20200202-41516-18c8t58.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=408&fit=crop&dpr=1 600w, https://images.theconversation.com/files/313185/original/file-20200202-41516-18c8t58.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=408&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/313185/original/file-20200202-41516-18c8t58.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=408&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/313185/original/file-20200202-41516-18c8t58.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=513&fit=crop&dpr=1 754w, https://images.theconversation.com/files/313185/original/file-20200202-41516-18c8t58.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=513&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/313185/original/file-20200202-41516-18c8t58.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=513&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A camel at the entrance to the Underwater Observatory Marine Park aquarium in the Israeli resort city of Eilat on Feb. 1, 2020. Camels are considered to have been a source of infection in MERS.</span>
<span class="attribution"><a class="source" href="http://gettyimages-1198066380-594x594.jpg">Photo by Artur Widak/NurPhoto via Getty Images</a></span>
</figcaption>
</figure>
<h2>No new virus under the Sun?</h2>
<p>Most “emergent” viruses that are new to humans are <a href="https://doi.org/10.1126/science.aap7463">regular inhabitants of other species</a>. In some cases, the animal hosts have reached a peaceful coexistence with their viruses, as in the case of <a href="https://doi.org/10.1016/j.chom.2018.01.006">bats</a>. In other cases, the viruses are as deadly in their wild animal hosts as in us, as with <a href="https://doi.org/10.1038/nature08200">chimpanzees and their immunodeficiency viruses</a>. Human activities have increased the rate of spillovers of wild animal viruses into our species, particularly from <a href="https://doi.org/10.1038/cddiscovery.2016.48">bats</a>.</p>
<p>Deforestation has brought bats closer to human habitations, <a href="https://doi.org/10.1038/srep41613">resulting in recurrent spread of Ebola from bats to humans</a> in sub-Saharan Africa. The trade in wild animals brought us SARS when <a href="https://doi.org/10.1007/978-3-540-70962-6_13">bats infected captive civets in a live-animal market</a> with the <a href="https://doi.org/10.1016/j.meegid.2009.09.015">virus</a>. Most profoundly, <a href="https://royalsocietypublishing.org/doi/10.1098/rstb.2010.0031">hunting chimpanzees in Cameroon brought humans HIV about a century ago</a>, most likely by way of an <a href="https://doi.org/10.3201/eid0805.01-0522">accident in handling an infected carcass</a>. </p>
<p>Other recent, emergent viruses have come to us from bats by way of our domestic animals. Hendra and Nipah virus spilled over in 1994 from fruit bats, by way of <a href="https://doi.org/10.1016/j.coviro.2016.02.004">horses</a> and <a href="https://doi.org/10.1016/j.coviro.2016.12.003">pigs in 1999</a>, respectively. In 2012 the MERS virus jumped to humans <a href="https://doi.org/10.1016/j.coviro.2016.01.004">from camels</a>, which were <a href="https://doi.org/10.1128/mBio.00373-17">originally infected from bats</a> several hundred years ago. Caring for our horses’ and camels’ runny noses was responsible for bringing us Hendra and MERS.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/313186/original/file-20200202-41532-i7csxi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/313186/original/file-20200202-41532-i7csxi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=391&fit=crop&dpr=1 600w, https://images.theconversation.com/files/313186/original/file-20200202-41532-i7csxi.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=391&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/313186/original/file-20200202-41532-i7csxi.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=391&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/313186/original/file-20200202-41532-i7csxi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=491&fit=crop&dpr=1 754w, https://images.theconversation.com/files/313186/original/file-20200202-41532-i7csxi.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=491&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/313186/original/file-20200202-41532-i7csxi.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=491&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Cows were the original source of measles, the most contagious disease on Earth.</span>
<span class="attribution"><span class="source">(Photo by ANGELA WEISS/AFP via Getty Images)</span></span>
</figcaption>
</figure>
<p>Going further into the past, scientists have determined that agricultural and domestic animals <a href="https://doi.org/10.1038/nature05775">delivered to us our most deadly pathogens</a>. For example, smallpox spilled over from <a href="https://doi.org/10.1016/j.meegid.2012.07.011">camels</a>, and measles came to us from <a href="https://doi.org/10.1186/1743-422X-7-52">cattle</a>, both many centuries ago. These virus infections were not a flash in the pan but stayed with us and infected most people as children until the recent past. If not for vaccines, these viruses would still be a routine and deadly part of childhood.</p>
<p>While scientists do not yet know the species origin of the new coronavirus, it is unsurprising that it emerged in a market containing an <a href="https://www.cbc.ca/news/health/coronavirus-zoonosis-1.5440146">astonishing variety of live animals</a>. </p>
<h2>How far will the novel coronavirus spread?</h2>
<p>Scientists quantify the ability of a virus to spread by <a href="https://wwwnc.cdc.gov/eid/article/25/1/17-1901_article">the statistic R0</a>, which measures the average number of people each contagious person infects. When each individual carrying a virus infects more than one person (R0>1), the virus can spread indefinitely. A happier outcome results when each infected person infects fewer than one person (R0<1), on average. Such viruses may spread briefly in humans but eventually will disappear from the human population. </p>
<p>At the moment, the novel coronavirus is transmitting at an <a href="https://www.who.int/news-room/detail/23-01-2020-statement-on-the-meeting-of-the-international-health-regulations-(2005)-emergency-committee-regarding-the-outbreak-of-novel-coronavirus-(2019-ncov)">R0 around 1.4-2.5</a>, which means it could continue to spread indefinitely. For comparison, <a href="https://doi.org/10.1186/1471-2334-14-480.">seasonal influenza viruses have a median R0 of 1.28</a>, a rate that allows them to spread every year around the globe.</p>
<p>R0 is a dynamic parameter that can change rapidly. The transmission rate can change upward as a result of the virus’ evolution and adaptation to humans, or downward by changes in human behavior and technology. </p>
<p>For example, in the recent West African Ebola outbreak, the virus spread from human to human to eventually infect <a href="https://www.who.int/csr/disease/ebola/en/">over 28,000 people</a>. In this time, <a href="https://doi.org/10.1016/j.cell.2016.10.013">the virus evolved</a> to become better at attaching to human cells, while becoming worse at attaching to cells of bats. This human-adapted lineage went extinct as the West African Ebola outbreak ended. The novel coronavirus could possibly follow suit and adapt to humans, thereby increasing its transmissibility.</p>
<h2>Behavior change in humans can reduce virus transmission</h2>
<p>Humans can combat the effects of viral evolution through behavioral changes that reduce virus transmission. For example, when SARS first emerged, it spread rapidly, with a high R0, eventually causing <a href="https://www.who.int/csr/sars/country/table2004_04_21/en/">8,098 cases and 774 deaths worldwide</a>. </p>
<p>However, SARS did not have the right stuff to spread indefinitely. It soon became clear that infected individuals were not contagious until after they displayed early symptoms such as <a href="https://doi.org/10.1043/1543-2165(2004)128%3C1346:SARSOW%3E2.0.CO;2">severe headaches and myalgia</a>. Thus, infected people could easily diagnose themselves and check into a hospital before infecting anyone. Hence, the R0 dropped to less than 1, which ensured eradication. </p>
<p>Like SARS, Ebola is terribly deadly and contagious, and also does not have the right stuff for persistence in humans. Ebola spreads through exposure to bodily fluids of an infected individual, but cannot be spread at a distance by sneezing or coughing. </p>
<p>The burial traditions of West Africans contributed significantly to the early and rapid outbreak of the virus, as family members directly <a href="https://doi.org/10.11694/pamj.supp.2015.22.1.6190">handled the body of the deceased</a>. When people started avoiding contact with the bodily fluids of those infected, either alive or deceased, Ebola’s transmission rate plummeted to an R0<1. The R0 of Ebola decreased through changes in behavior alone, <a href="https://doi.org/10.11694/pamj.supp.2015.22.1.6190">even in the most rural villages</a>, without the benefit of newly developed therapies and vaccines.</p>
<p>So far, it seems scientists and health care workers may not be so lucky in containing the novel coronavirus because it is transmissible even <a href="https://doi.org/10.1038/nature05775">before symptoms arise</a>. However, transmission will certainly be reduced if we follow familiar protocols for preventing cold and flu infection, such as <a href="https://www.cdc.gov/coronavirus/2019-ncov/hcp/guidance-prevent-spread.html">self-quarantine</a>,<a href="http://www.wesleyanarcadia.com/spring-2019/how-we-can-all-share-the-fight-against-infectious-disease">handwashing and generally avoiding others’ germs</a>.</p>
<h2>Beyond behavioral modification</h2>
<p>Medical technology may provide solutions going forward. One promising effort is a <a href="https://www.mobihealthnews.com/news/asia-pacific/veredus-laboratories-announces-development-detection-kit-wuhan-coronavirus">portable detection kit</a>. The VereCoV detection kit can detect and distinguish among three coronaviruses, SARS, MERS and 2019-nCoV within just two hours. Long-term technological efforts may eventually include drug therapies and vaccination.</p>
<p>The stakes for containing the novel coronavirus are high. If health officials can reduce virus transmission toward R0<1 through changes in behavior or through technology, we may reach eradication as seen globally in SARS and at least locally in Ebola. </p>
<p>But if the virus continues to spread at its current rate, or at an even higher rate through its evolution, the novel coronavirus could be with us indefinitely. The virus would then join the ranks of <a href="https://doi.org/10.1038/nature05775">persistent viruses our species has accumulated</a> over millennia from animals people have hunted or domesticated. It may take a <a href="http://www.wesleyanarcadia.com/spring-2019/how-we-can-all-share-the-fight-against-infectious-disease">combination of changes</a> in individual behavior, investment in the public health abroad, and the development of new technologies for the novel outbreak to end happily. </p>
<p>[ <em>Deep knowledge, daily.</em> <a href="https://theconversation.com/us/newsletters?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=deepknowledge">Sign up for The Conversation’s newsletter</a>. ]</p><img src="https://counter.theconversation.com/content/130790/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Some of the world’s worst diseases have come from animals. Bats, cows, camels and horses have all contributed. Now, scientists are working to know which animal introduced the new coronavirus.Frederick Cohan, Huffington Foundation Professor of Biology in the College of the Environment, Wesleyan UniversityKathleen Sagarin, Doctoral candidate, Biology, Wesleyan UniversityKelly Mei, Research assistant, Wesleyan UniversityLicensed as Creative Commons – attribution, no derivatives.