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This new tech could spell end for mouse plagues

<p dir="ltr">Invasive mice populations could be a thing of the past, thanks to a new genetic tool developed by a team of Australian scientists.</p> <p dir="ltr">Researchers at the University of Adelaide have developed t-CRISPR, which uses gene editing technology to alter the fertility gene in laboratory mice to make females infertile.</p> <p dir="ltr">“This is the first time that a new genetic tool has been identified to suppress invasive mouse populations by inducing female infertility,” said lead researcher Professor Paul Thomas.</p> <p dir="ltr">“The t-CRISPR approach uses cutting-edge DNA editing technology to make alterations to a female fertility gene. Once the population is saturated with the genetic modification, all the females that are generated will be infertile.</p> <p dir="ltr">“We are also developing new versions of t-CRISPR technology that are designed to target specific pest populations to prevent unwanted spread of the gene drive.”</p> <p dir="ltr">The new tool is based on an existing technology, CRISPR-Cas9 gene editing, which has largely been applied to limiting the spread of malaria by making male mosquitoes infertile.</p> <p dir="ltr"><strong>CRISPR 101</strong></p> <p dir="ltr">Since it was unveiled in 2012, the CRISPR method has been used to edit pieces of DNA inside the cells of organisms, primarily insects.</p> <p dir="ltr">“Up until now, this technology has been aimed at insects to try and limit the spread of malaria, which causes up to 500,000 deaths worldwide per year,” Luke Gierus, a post-graduate student and the paper’s co-first author, said.</p> <p dir="ltr">The technology relies on the Cas9 protein found in bacteria, which scientists can program to find and bind to almost any 20-letter sequence of DNA in a gene with the help of a piece of RNA that matches the target DNA sequence.</p> <p dir="ltr">When it finds the target, standard CRISPR cuts the DNA, and the process of repairing the DNA introduces mutations that can disable the gene.</p> <p dir="ltr">Other variations of CRISPR can also replace faulty genes, turn genes on or off, or change one letter of the DNA code to another.</p> <p dir="ltr">In this study, the team simulated what would happen when an edited version of a fertility gene on chromosome 17, which affects the ability of sperm to swim, was introduced to populations of mice. </p> <p dir="ltr">Males who carry one copy of this gene are infertile, while females are still fertile but only have one functioning version of the gene and can pass on either the functioning or non-functioning version to their offspring.</p> <p dir="ltr">In females that had a second edited chromosome that affected their fertility, they found that male offspring would all be infertile, while only 50 percent of female offspring would be fertile.</p> <p dir="ltr">They found that 250 mice with modified genes could eradicate a population of 200,000 mice on an island in around 20 years.</p> <p dir="ltr">“The use of t-CRISPR technology provides a humane approach to controlling invasive mice without the release of toxins into the environment. We are also working on strategies to prevent failed eradication due to the emergence of gene drive resistance in the target population,” Gierus said.</p> <p dir="ltr">While t-CRISPR has been developed to specifically target mice, CSIRO Group Leader for Environmental Mitigation and Resilience Dr Owain Edwards said it could be developed to use on other invasive animals.</p> <p dir="ltr">The researchers, who collaborated with CSIRO, the Centre for Invasive Species Solutions, the Genetic Biocontrol for Invasive Rodents (GBIRd) consortium and the US Department of Agriculture, were supported by both the South Australian and NSW governments.</p> <p dir="ltr">“These promising findings demonstrate how gene drive technology may be a game changer in managing the impacts of mice on our environment, community, and agricultural sector,” South Australian Deputy Premier Dr Susan Close said.</p> <p dir="ltr">“This cutting-edge research also highlights the global leadership of the South Australian research sector, in finding solutions to social, environmental and economic challenges.</p> <p dir="ltr">“The South Australian Government is proud to have supported this proof-of-concept, having granted the University of Adelaide $1 million through the Research and Innovation Fund.”</p> <p dir="ltr">They published their findings in the journal <em><a href="https://doi.org/10.1073/pnas.2213308119" target="_blank" rel="noopener">Proceedings of the National Academy of Sciences</a></em>.</p> <p><span id="docs-internal-guid-bca82366-7fff-dcca-05a4-83502245beac"></span></p> <p dir="ltr"><em>Image: ABC News</em></p>

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Barcelona plagued by hoards of wild boars

<p><span style="font-weight: 400;">Barcelona has been battling an influx of wild boars, with many venturing into the city and digging through bins and even attacking celebrities.</span></p> <p><span style="font-weight: 400;">Latin pop star </span><a rel="noopener" href="https://oversixty.com.au/travel/travel-trouble/shakira-claims-she-was-attacked-and-robbed-by-wild-boars-in-barcelona" target="_blank"><span style="font-weight: 400;">Shakira</span></a><span style="font-weight: 400;"> had to fight off several boars in September while walking in a park with her eight-year-old son. Though she made light of the incident on social media, local experts have taken action to manage the problem, which has been exacerbated by COVID-19 lockdowns.</span></p> <p><img style="width: 0px; height: 0px;" src="https://oversixtydev.blob.core.windows.net/media/7845846/boars1.jpg" alt="" data-udi="umb://media/1bacf4d303274553ac4d695fff1f1b1f" /></p> <p><em><span style="font-weight: 400;">A wild boar foraging in Molins de Rei, Barcelona in 2020. Image: Getty Images</span></em></p> <p><span style="font-weight: 400;">“So many wild boars in Barcelona, because in this case Barcelona is acting as an ecological sink,” veterinarian Carles Conejero told the</span> <em><a rel="noopener" href="https://www.bbc.com/news/av/world-europe-59352740" target="_blank"><span style="font-weight: 400;">BBC</span></a></em><span style="font-weight: 400;">.</span></p> <p><span style="font-weight: 400;">“It means that the excess of wild boar population, they see Barcelona [as] a suitable environment to disperse.” </span></p> <p><span style="font-weight: 400;">City Hall has been trapping the wild animals, then taking samples before killing them humanely.</span></p> <p><span style="font-weight: 400;">Though the decision has upset animal rights groups, Carles has said it has become necessary.</span></p> <p><span style="font-weight: 400;"> “When they are piglets they are so nice and they are not dangerous,” he explained.</span></p> <p><span style="font-weight: 400;">“But when they grow and they cause problems, they attack humans [and] dogs or they cause traffic accidents, then [they] are the animals that we need to remove.”</span></p> <p><em><span style="font-weight: 400;">Image: Getty Images</span></em></p>

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New vaccine trial targets 2000-year-old virus

<p><span style="font-weight: 400;">The researchers behind the AstraZeneca COVID-19 vaccine have started a new trial to treat a much older disease: the plague.</span></p> <p><span style="font-weight: 400;">In the phase-one trial, scientists at the University of Oxford will be testing a new vaccine for the ancient virus on at least 40 healthy volunteers aged between 18 and 55.</span></p> <p><span style="font-weight: 400;">The new vaccine, which uses the same technology as the AstraZeneca jab, is being trialled to check how well the body recognises and learns how to fight the plague after vaccination.</span></p> <p><span style="font-weight: 400;">Though the virus hasn’t been seen in most of the world since the Black Death swept through Europe in the 14th century, there are still cases in some rural areas of Africa, Asia and America.</span></p> <p><span style="font-weight: 400;">Between 2010 and 2015, 3,248 cases of the plague were reported globally, including 584 deaths.</span></p> <blockquote style="background: #FFF; border: 0; border-radius: 3px; box-shadow: 0 0 1px 0 rgba(0,0,0,0.5),0 1px 10px 0 rgba(0,0,0,0.15); margin: 1px; max-width: 540px; min-width: 326px; padding: 0; width: calc(100% - 2px);" class="instagram-media" data-instgrm-captioned="" data-instgrm-permalink="https://www.instagram.com/p/CSJQK9CLXF5/?utm_source=ig_embed&amp;utm_campaign=loading" data-instgrm-version="13"> <div style="padding: 16px;"> <div style="display: flex; flex-direction: row; align-items: center;"> <div style="background-color: #f4f4f4; border-radius: 50%; flex-grow: 0; height: 40px; margin-right: 14px; width: 40px;"></div> <div style="display: flex; flex-direction: column; flex-grow: 1; justify-content: center;"> <div style="background-color: #f4f4f4; border-radius: 4px; flex-grow: 0; height: 14px; margin-bottom: 6px; width: 100px;"></div> <div style="background-color: #f4f4f4; border-radius: 4px; flex-grow: 0; height: 14px; width: 60px;"></div> </div> </div> <div style="padding: 19% 0;"></div> <div style="display: block; height: 50px; margin: 0 auto 12px; width: 50px;"></div> <div style="padding-top: 8px;"> <div style="color: #3897f0; font-family: Arial,sans-serif; font-size: 14px; font-style: normal; font-weight: 550; line-height: 18px;">View this post on Instagram</div> </div> <p style="color: #c9c8cd; font-family: Arial,sans-serif; font-size: 14px; line-height: 17px; margin-bottom: 0; margin-top: 8px; overflow: hidden; padding: 8px 0 7px; text-align: center; text-overflow: ellipsis; white-space: nowrap;"><a style="color: #c9c8cd; font-family: Arial,sans-serif; font-size: 14px; font-style: normal; font-weight: normal; line-height: 17px; text-decoration: none;" rel="noopener" href="https://www.instagram.com/p/CSJQK9CLXF5/?utm_source=ig_embed&amp;utm_campaign=loading" target="_blank">A post shared by Oxford Vaccine Group (@oxford_vaccinegroup)</a></p> </div> </blockquote> <p><span style="font-weight: 400;">Just two years later, </span><a rel="noopener" href="https://www.ox.ac.uk/news/2021-07-26-phase-i-trial-begins-new-vaccine-against-plague" target="_blank"><span style="font-weight: 400;">an epidemic</span></a><span style="font-weight: 400;"> in Madagascar saw 2,119 suspected cases and 171 deaths over several months.</span></p> <p><span style="font-weight: 400;">With many of the regions at risk of outbreaks being in remote locations, a vaccine could be a new way to protect these communities.</span></p> <p><span style="font-weight: 400;">Larissa, 26, studies genetics at the University of Oxford and is one of the participants who hopes she can help save lives by getting the jab.</span></p> <p><img style="width: 500px; height: 281.25px;" src="https://oversixtydev.blob.core.windows.net/media/7843432/_119964702_capture.png" alt="" data-udi="umb://media/faa0b5599bbf49738fdbc2a4e0278892" /></p> <p><em><span style="font-weight: 400;">Image: Oxford University</span></em></p> <p><span style="font-weight: 400;">“I’m lucky enough to live in a time where vaccines are being developed,” Larissa said.</span></p> <p><span style="font-weight: 400;">“And so, when I saw that there was a study aiming at developing a vaccine against a disease that’s been around for 2000 years and has killed millions and millions of people, I didn’t hesitate, I just wanted to do my bit.”</span></p> <p><span style="font-weight: 400;">When asked if she was worried about side effects, Larissa said she wasn’t “too concerned”.</span></p> <p><span style="font-weight: 400;">“The vaccine that’s being assessed today is using the same platform as the Covid vaccine, which has literally been administered to millions of people around the world.”</span></p> <p><span style="font-weight: 400;">Like the Oxford-AstraZeneca Covid vaccine, the plague vaccine uses a weakened version of adenovirus - a common-cold virus from chimpanzees - that has been genetically altered so people do not get infected.</span></p> <p><span style="font-weight: 400;">The vaccine does not contain plague bacterium, meaning recipients of the jab cannot contract the plague.</span></p> <p><span style="font-weight: 400;">Instead, the adenovirus has additional genes that make proteins from </span><span style="font-weight: 400;">Yersinia pestis</span><span style="font-weight: 400;">, the plague bacterium.</span></p> <p><span style="font-weight: 400;">With these added genes, the vaccine should be able to teach the immune systems of recipients how to fend off a real infection of the plague if it needs to.</span></p> <p><span style="font-weight: 400;">This technique could also be used against other diseases, according to the researchers.</span></p> <p><span style="font-weight: 400;">“We’ve already done clinical trials using similar technology against a bacterium, meningitis B, and a virus, Zika,” Dr Maheshi Ramasamy, the senior clinical researcher of the Oxford Vaccine Group, said.</span></p> <p><span style="font-weight: 400;">“But we’re also looking to develop vaccines against new and emerging diseases such as Lassa fever or the Marburg virus.”</span></p> <p><span style="font-weight: 400;">The plague vaccine trial is expected to run for at least a year.</span></p>

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Suspected bubonic plague case leads to epidemic fears

<p>Authorities in China have issued a warning after a suspected bubonic plague case was reported in the Inner Mongolia Autonomous Region.</p> <p>Residents in the Bayannur district have been ordered not to hunt and eat wild animals after a herdsman was confirmed to have <a href="https://www.nytimes.com/2020/07/06/world/asia/china-bubonic-plague-inner-mongolia.html">caught the disease on Sunday</a>.</p> <p>Another patient, a 15-year-old boy, was also suspected to be infected on Monday after developing a fever following contact with a marmot hunted by a dog, according to <em><a href="https://twitter.com/globaltimesnews/status/1280031821980303360">Global Times</a></em>.</p> <p>Health officials of the city of Bayan Nur have placed a third-level alert until the end of the year and asked the public to report any sick or dead marmots.</p> <p>“At present, there is a risk of a human plague epidemic spreading in this city. The public should improve its self-protection awareness and ability, and report abnormal health conditions promptly," said a local health authority, as quoted by the <a href="https://www.chinadaily.com.cn/a/202007/05/WS5f01d743a310834817257493.html"><em>China Daily</em> newspaper</a>.</p> <p>Bubonic plague is a bacterial infection commonly spread through fleas from small animals. It was the cause of the Black Death pandemic that killed an estimated 50 million people across Asia, Europe and Africa in the 14th century.</p> <p>The disease can now be treated with a number of antibiotics, such as gentamicin and doxycycline.</p> <p>Symptoms of the plague include high fever, headaches, nausea and swollen lymph nodes.</p> <p>While plague outbreaks have become increasingly rare in China, occasional cases are still reported. According to <em><a href="https://www.theguardian.com/world/2020/jul/06/suspected-case-of-bubonic-plague-found-in-city-in-inner-mongolia-china">Reuters</a></em>, China reported 26 cases and 11 deaths from 2009 to 2018.</p>

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Guide to the Classics: Albert Camus' The Plague

<p>Some weeks ago, I got an email from a student who had returned to Northern Italy over Christmas to see family.</p> <p>Unable to return to Australia, they were in lockdown. The hospitals were filling up fast, as COVID-19 <a href="https://epidemic-stats.com/coronavirus/italy">began to spiral out of control</a>. Sales of Albert Camus’ 1947 novel <em><a href="https://www.goodreads.com/book/show/11989.The_Plague?from_search=true&amp;from_srp=true&amp;qid=lkEWcCTf5p&amp;rank=1">The Plague</a></em> (<em>La Peste</em>) were <a href="https://www.theguardian.com/books/2020/mar/28/albert-camus-novel-the-plague-la-peste-pestilence-fiction-coronavirus-lockdown">spiking</a>. Everyone was buying it.</p> <p>Rereading <em>The Plague</em> over these past weeks has been an uncanny experience. Its fictive chronicle of the measures taken in the city of Oran against a death-dealing disease that strikes in 1940 sometimes seemed to blur into the government announcements reshaping our lives.</p> <p>Oran is a city like anywhere else, Camus’ narrator tells us:</p> <blockquote> <p>Our citizens work hard, but solely with the object of getting rich. Their chief interest is in commerce, and their chief aim in life is, as they call it, ‘doing business’.</p> </blockquote> <p>Like people anywhere else, the Oranians are completely unprepared when rats begin emerging from the sewers to die in droves in streets and laneways. Then, men, women and children start to fall ill with high fever, difficulties breathing and fatal buboes.</p> <p>The people of Oran initially “disbelieved in pestilences”, outside of the pages of history books. So, like many nations in 2020, they are slow to accept the enormity of what is occurring. As our narrator comments drily: “In this respect they were wrong, and their views obviously called for revision.”</p> <p>The numbers of afflicted rise. First slowly, then exponentially. By the time the plague-bearing spring gives way to a sweltering summer, over 100 deaths daily is the new normal.</p> <p>Emergency measures are rushed in. The city gates are shut, and martial law declared. Oran’s commercial harbour is closed to sea traffic. Sporting competitions cease. Beach bathing is prohibited.</p> <p>Soon, food shortages emerge (toilet paper, thankfully, is not mentioned). Some Oranians turn plague-profiteers, preying on the desperation of their fellows. Rationing is brought in for basic necessities, including petrol.</p> <p>Meanwhile, anyone showing symptoms of the disease is isolated. Houses, then entire suburbs, are locked down. The hospitals become overwhelmed. Schools and public buildings are <a href="https://www.pharmaceutical-technology.com/comment/excel-convention-centre-covid-19/">converted</a> into makeshift plague hospitals.</p> <p style="text-align: center;"><iframe width="440" height="260" src="https://www.youtube.com/embed/L8Dyf-wules?wmode=transparent&amp;start=0" frameborder="0" allowfullscreen=""></iframe></p> <p style="text-align: center;"><span class="caption">A convention centre in London has been transformed into a 4,000-bed hospital.</span></p> <p>Our key protagonists, Dr Rieux and his friends Tarrou, Grand and Rambert, set up teams of voluntary workers to administer serums and ensure the sick are quickly diagnosed and hospitalised, often amongst harrowing scenes.</p> <p>In these circumstances, fear and suspicion descend “dewlike, from the greyly shining sky” on the population. Everyone realises that anyone – even those they love – could be a carrier.</p> <p>Come to think of it, so could each person themselves.</p> <p>The failure of the governors to consistently impose “social distancing” is shown up spectacularly in the novel’s most picturesque scene. The lead actor in a rendition of Gluck’s <a href="https://www.youtube.com/watch?v=EENw_ptgGcg">Orpheus and Eurydice</a> collapses onstage, “his arms and legs splayed out under his antique robe”.</p> <p>Terrified patrons flee the darkened underworld of the opera house, “wedged together in the bottlenecks, and pouring out into the street in a confused mass, with shrill cries of dismay”.</p> <p>Arguably the most telling passages in <em>The Plague</em> today are Camus’ beautifully crafted meditative observations of the social and psychological effects of the epidemic on the townspeople.</p> <p>Epidemics make exiles of people in their own countries, our narrator stresses. Separation, isolation, loneliness, boredom and repetition become the shared fate of all.</p> <p>In Oran, as in Australia, places of worship go empty. Funerals are banned for fear of contagion. The living can no longer even farewell the many dead.</p> <p>Camus’ narrator pays especial attention to the damages visited by the plague upon separated lovers. Outsiders like the journalist Rambert who, by chance, are marooned inside Oran when the gates shut are “in the general exile […] the most exiled”.</p> <p>Today’s world knows many such “travellers caught by the plague and forced to stay where they were, […] cut off both from the person(s) with whom they wanted to be and from their homes as well”.</p> <p><strong>Multiple allegories</strong></p> <p>Camus’ prescient account of life under conditions of an epidemic works on different levels. <em>The Plague</em> is a transparent allegory of the Nazi occupation of France beginning in spring 1940. The sanitary teams reflect Camus’ experiences in, and admiration for, the resistance against the “<a href="https://www.dukeupress.edu/the-brown-plague/?viewby=title">brown plague</a>” of fascism.</p> <p>Camus’ title also evokes the ways the Nazis characterised those they targeted for extermination as <a href="https://encyclopedia.ushmm.org/content/en/article/defining-the-enemy">a pestilence</a>. The shadow of the then-still-recent Holocaust darkens <em>The Plague</em>’s pages.</p> <p>When death rates become so great that individual burials are no longer possible – as in <a href="https://www.youtube.com/watch?v=VFy3_hEBcy8">scenes we are already seeing</a> – the Oranaise dig collective graves into which:</p> <blockquote> <p>the naked, somewhat contorted bodies were slid into a pit almost side by side, then covered with a layer of quicklime and another of earth […] so as to leave space for subsequent consignments.</p> </blockquote> <p>When this measure fails to keep up with the weight of these “consignments”, as with the genocidal actions of the <em><a href="https://www.britannica.com/topic/Einsatzgruppen">Einzatsgruppen</a></em>, “the old crematorium east of the town” is repurposed. Closed streetcars filled with the dead are soon rattling along the old coastal tramline:</p> <blockquote> <p>Thereafter, […] when a strong wind was blowing […] a faint, sickly odour coming from the east remind[ed] them that they were living under a new order and that the plague fires were taking their nightly toll.</p> </blockquote> <p>Camus’ plague is also a metaphor for the force of what Dr Rieux calls “abstraction” in our lives: all those impersonal rules and processes which can make human beings statistics to be treated by governments with all the inhumanity characterising epidemics.</p> <p>For this reason, the enigmatic character Tarrou identifies the plague with people’s propensity to rationalise killing others for philosophical, religious or ideological causes. It is with this sense of plague in mind that the final words of the novel warn:</p> <blockquote> <p>that the plague bacillus never dies or disappears for good; that it can lie dormant for years and years in furniture and linen-chests; that it bides its time in bedrooms, cellars, trunks, and bookshelves; and that perhaps the day would come when, for the bane and the enlightening of men, it would rouse up its rats again and send them forth to die in a happy city.</p> </blockquote> <p><strong>Ordinary hope</strong></p> <p>There is nevertheless truth in the description of Camus’ masterwork as a “<a href="https://www.theglobeandmail.com/arts/books/article-the-hope-at-the-heart-of-albert-camuss-plague-novel-la-peste/">sermon of hope</a>”. In the end, the plague dissipates as unaccountably as it had begun. Quarantine is lifted. Oran’s gates are reopened. Families and lovers reunite. The chronicle closes amid scenes of festival and jubilation.</p> <p>Camus’ narrator concludes that confronting the plague has taught him that, for all of the horrors he has witnessed, “there are more things to admire in men than to despise”.</p> <p>Unlike some philosophers, Camus became <a href="https://www.pdcnet.org/philtoday/content/philtoday_2017_0999_10_2_177">increasingly sceptical</a> about glorious ideals of superhumanity, heroism or sainthood. It is the capacity of ordinary people to do extraordinary things that <em>The Plague</em> lauds. “There’s one thing I must tell you,” Dr Rieux at one point specifies:</p> <blockquote> <p>there’s no question of heroism in all this. It’s a matter of common decency. That’s an idea which may make some people smile, but the only means of fighting a plague is common decency.</p> </blockquote> <p>It is such ordinary virtue, people each doing what they can to serve and look after each other, that Camus’ novel suggests alone preserves peoples from the worst ravages of epidemics, whether visited upon them by natural causes or tyrannical governments.</p> <p>It is therefore worth underlining that the unheroic heroes of Camus’ novel are people we call healthcare workers. Men and women, in many cases volunteers, who despite great risks step up, simply because “plague is here and we’ve got to make a stand”.</p> <p>It is also to these people’s examples, <em>The Plague</em> suggests, that we should look when we consider what kind of world we want to rebuild after the gates of our cities are again thrown open and COVID-19 has become a troubled memory.<!-- Below is The Conversation's page counter tag. Please DO NOT REMOVE. --><img style="border: none !important; box-shadow: none !important; margin: 0 !important; max-height: 1px !important; max-width: 1px !important; min-height: 1px !important; min-width: 1px !important; opacity: 0 !important; outline: none !important; padding: 0 !important; text-shadow: none !important;" src="https://counter.theconversation.com/content/134244/count.gif?distributor=republish-lightbox-basic" alt="The Conversation" width="1" height="1" /><!-- End of code. If you don't see any code above, please get new code from the Advanced tab after you click the republish button. The page counter does not collect any personal data. More info: https://theconversation.com/republishing-guidelines --></p> <p><em><a href="https://theconversation.com/profiles/matthew-sharpe-125260">Matthew Sharpe</a>, Associate Professor in Philosophy, <a href="https://theconversation.com/institutions/deakin-university-757">Deakin University</a></em></p> <p><em>This article is republished from <a href="https://theconversation.com">The Conversation</a> under a Creative Commons license. Read the <a href="https://theconversation.com/guide-to-the-classics-albert-camus-the-plague-134244">original article</a>.</em></p>

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Pet health alert: “Cat plague” returns after almost 40 years

<p><em><strong>Mark Westman is a Veterinarian and Postdoctoral Researcher at the University of Sydney. Richard Malik is a Veterinary Internist (Specialist) at the University of Sydney.</strong></em></p> <p>A deadly feline disease is now spreading between cats after hiding in nature for nearly 40 years. Multiple cases of feline parvovirus, also known as cat plague, or panleukopenia, have been reported in stray kittens in <span style="text-decoration: underline;"><strong><a href="https://www.google.com/url?hl=en&amp;q=https://thenewdaily.com.au/news/state/vic/2018/02/04/cat-pnaleukopenia-virus-melbourne/?utm_source%3DResponsys%26utm_medium%3Demail%26utm_campaign%3D20180205_TND&amp;source=gmail&amp;ust=1517980371408000&amp;usg=AFQjCNF16d0S8bAtSYb_D3kjCUhljbClBA" target="_blank">the greater Melbourne area</a></strong></span> this week.</p> <p>Feline parvovirus was a common disease in the 1960s and 1970s. Australia was one of the first countries to develop an effective vaccine. Once widespread vaccination became routine, the disease was pushed back into nature.</p> <p>In the 1970s, cases were typically seen in unvaccinated kittens purchased from markets or pet stores, and in shelters where vaccination protocols were lax.</p> <p>Between the early 1980s and 2015, cases were unreported, but no doubt feral and semi-owned cats were still sporadically infected.</p> <p>The re-emergence first occurred in animal shelters in <span style="text-decoration: underline;"><strong><a href="http://www.ava.com.au/node/86283" target="_blank">Mildura and Melbourne in 2016</a></strong></span> and <span style="text-decoration: underline;"><strong><a href="http://www.smh.com.au/nsw/feline-panleukopenia-virus-resurfaces-in-western-sydney-after-40-years-20170207-gu7qab.html" target="_blank">south-western Sydney in 2016</a></strong></span>. Many cats died. Even survivors suffered greatly. In all these outbreaks, affected cats had one thing in common – they had not been vaccinated.</p> <p><strong>What is feline parvovirus and how does it kill?</strong></p> <p>Feline parvovirus has a predilection for infecting rapidly dividing tissues. Cells lining the small intestine of infected cats are killed, resulting in vomiting, diarrhoea (often bloody), fever, lethargy, anorexia and sometimes sudden death.</p> <p>The bone marrow is transiently wiped out by the virus, resulting in a depletion of white blood cells. As a result, infected cats are unable to fight the invasion by secondary bacteria that attack the leaky gut wall.</p> <p>Most cases of feline parvovirus are in unvaccinated kittens or young cats. The welfare of cats is hugely impacted by this terrible disease – it makes cats miserable for many days, if they survive.</p> <p>Treatment involves intensive therapy in hospital: intravenous fluids by infusion pump, medication to reduce vomiting, expensive anti-viral treatment (omega-interferon), opioids for pain relief, antibiotics to treat secondary bacterial infections, and occasionally blood or plasma transfusions and nutritional support (feeding tubes).</p> <p>Treatment can costs thousands of dollars, and many owners just can’t afford it. But even with treatment, the fatality rate remains high.</p> <p>Feline parvovirus is spread by faeco-oral contamination: from infected cats shedding virus in their faeces. Litter trays and natural latrines (such as sandboxes) are prime sources of infection.</p> <p>This may occur where infected cats are kept close to uninfected cats (in shelters and pounds), and in homes where cats have outdoor access. But you can track feline parvovirus into your house on your shoes or clothing, so even 100% indoor cats are not safe.</p> <p>Feline parvovirus can usually be quickly diagnosed by veterinarians using rapid point-of-care test kits and then confirmed in a lab.</p> <p>There is no risk of this virus spreading to human patients.</p> <p><strong>How did it re-emerge?</strong></p> <p>Feline parvovirus was never completely eliminated from the Australian cat population and instead has been maintained at low levels in the unowned and feral cat population for the past 40 years. Remember, there are perhaps six times as many unowned cats than owned cats in Australia!</p> <p>This adaptable virus also has the potential to infect foxes and wild dogs, only later to be passed back to cats, providing a variety of potential environmental reservoirs.</p> <p>Perhaps with an increased effort to rehabilitate and rehome “fringe dwelling cats”, it was inevitable that the virus would spill back from these unvaccinated cats into the general pet cat population, given waning herd immunity.</p> <p>Consistent with this hypothesis is the first outbreak occurring in rural Mildura, a somewhat underprivileged socioeconomic area (<span style="text-decoration: underline;"><strong><a href="http://www.heraldsun.com.au/news/opinion/were-proud-of-mildura-and-well-beat-this-evil/news-story/1292c3704b2ee2d989cc32aed5fafe0f" target="_blank">government figures show</a></strong></span><strong> </strong>the median household income is A$878 per week), and subject to incursions by feral cats, foxes and wild dogs – including dogs used for hunting.</p> <p>It is our suspicion that the cost of vaccinating the family cat (currently more than A$200 for a kitten requiring a course of two to three vaccines) exceeds the budget for many pet owners.</p> <p>The best protection for any cat (and every cat) is widespread vaccination of as many cats as possible in the community at large. This “herd immunity” is the best protection against this highly contagious, persistent, resistant virus. When vaccination rates fall below 70%, cat populations are in trouble.</p> <p><strong>How do we protect pet cats?</strong></p> <p>Vaccination against feline parvovirus is highly effective (more than 99%) and is given by veterinarians as part of an <span style="text-decoration: underline;"><strong><a href="https://www.ncbi.nlm.nih.gov/pubmed/26101309" target="_blank">F3 or F4 vaccine</a></strong></span> at the same time as a routine health check.</p> <p>The Australian Veterinary Association recently recommended all cats be vaccinated annually. But with the modern range of vaccines, there is <span style="text-decoration: underline;"><strong><a href="https://www.wsava.org/sites/default/files/WSAVA%20Vaccination%20Guidelines%202015%20Full%20Version.pdf" target="_blank">good evidence that in kittens older than 16 weeks</a></strong></span>, a single vaccination produces immunity which last several years</p> <p>If a kitten has received two or three kitten vaccinations (the last one at 16-18 weeks of age), and a booster one year later, it likely has excellent protection against the virus, probably for several years, and possibly for life.</p> <p>If your adult cat has received an annual vaccination in the past three years, it likely has excellent protection.</p> <p>If your cat is more than three years overdue for its vaccination, it is sensible to visit your local veterinarian soon. Your cat will develop or maintain excellent protection within a few days of vaccination.</p> <p><strong>But what about unowned and feral cats?</strong></p> <p>We need to support efforts to vaccinate cats that have never been vaccinated against feline parvovirus – cats owned by people who are unable to afford vaccinations, and cats that have been dumped and are now unowned and free-roaming.</p> <p>New South Wales is making some progress in this area. The NSW Cat Protection Society responded to a 2017 outbreak by <span style="text-decoration: underline;"><strong><a href="https://www.dailytelegraph.com.au/newslocal/inner-west/cat-protection-society-to-subsidise-vaccinations-after-outbreaks-of-feline-virus/news-story/532b6a9be0e5b5aed95faa50380d18c2" target="_blank">subsidising free vaccinations</a></strong></span> for cat owners in Sydney. RSPCA NSW has ongoing <span style="text-decoration: underline;"><strong><a href="https://www.rspcansw.org.au/what-we-do/working-in-communities/community-animal-welfare-scheme-caws/" target="_blank">targeted low-cost vaccination programs</a></strong></span> for cat owners, particularly in regional and remote areas of NSW.</p> <p><span style="text-decoration: underline;"><strong><a href="https://www.petwelfare.org.au/2017/07/06/managing-cats-humanely-scientifically-reduce-cat-numbers-wildlife-predation-costs/" target="_blank">Trap-neuter and return programs</a></strong></span>, while controversial, usually involve administering a F3/F4 vaccination to unowned and feral cats, thereby boosting herd immunity against feline parvovirus and also possibly reducing cat numbers.</p> <p>Finally, for people who cannot afford veterinary care because of their life circumstances, <span style="text-decoration: underline;"><strong><a href="http://www.petsinthepark.org.au/" target="_blank">Pets in the Park</a></strong></span> and similar charities can provide another option for vaccination.</p> <p>Remember, the larger the proportion of the cat population that is vaccinated, the less chance any cat and every cat has of becoming infected. Stated another way, it’s far more effective to maximise the proportion of the cat population that is vaccinated, rather than over-vaccinating only a limited proportion of cats.</p> <p><em>Written by Mark Westman and Richard Malik. Republished with permission of <a href="http://theconversation.com/" target="_blank"><strong><span style="text-decoration: underline;">The Conversation</span></strong></a>. </em><img width="1" height="1" src="https://counter.theconversation.com/content/91234/count.gif?distributor=republish-lightbox-advanced" alt="The Conversation"/></p>

Family & Pets