{"id":2536,"date":"2023-02-10T21:26:41","date_gmt":"2023-02-11T03:26:41","guid":{"rendered":"https:\/\/www.unmc.edu\/healthsecurity\/transmission\/?p=2536"},"modified":"2023-02-10T21:26:43","modified_gmt":"2023-02-11T03:26:43","slug":"as-bird-flu-spreads-to-mammals-health-officials-urge-caution","status":"publish","type":"post","link":"https:\/\/www.unmc.edu\/healthsecurity\/transmission\/2023\/02\/10\/as-bird-flu-spreads-to-mammals-health-officials-urge-caution\/","title":{"rendered":"As Bird Flu Spreads to Mammals, Health Officials Urge Caution"},"content":{"rendered":"
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(Smithsonian Magazine<\/a>) <\/p>\n\n\n\n

Amid a global bird die-off from avian flu, officials have also noticed the deadly virus strain, called H5N1, infecting a growing number of mammals. This week, the World Health Organization (WHO) urged authorities to remain vigilant\u2014but not panic\u2014about the virus\u2019s potential risk to humans.<\/p>\n\n\n\n

\u201cThe recent spillover to mammals needs to be monitored closely,\u201d\u00a0Tedros Adhanom Ghebreyesus<\/a>, the WHO\u2019s director-general, told reporters on Wednesday, according to the\u00a0Agence France-Presse<\/a>\u00a0(AFP). But \u201cfor the moment, WHO assesses the risk to humans as low.\u201d <\/p>\n\n\n\n

Avian flu is not adapted to infect people, making human cases rare and person-to-person transmission even more difficult. But experts say that the more H5N1 spreads among animals, the more likely it is to evolve into a variant that can jump to humans, per the AFP.<\/p>\n\n\n\n

Despite the current low risk to public health, officials must prepare \u201cto face outbreaks in humans, and be ready also to control them as soon as possible,\u201d Sylvie Briand<\/a>, director of Global Infectious Hazard Preparedness and Emergency Preparedness at the WHO, tells Fortune<\/em><\/a>\u2019s Erin Prater.<\/p>\n\n\n\n

H5N1 was first detected in domestic waterfowl in 1996 and spread to migratory birds around 2005. Then, these long-distance fliers carried the virus across the world, writes\u00a0Science<\/em><\/a>\u2019sKai Kupferschmidt. Over that time, the virus has infected relatively few humans\u2014but those cases have proven deadly. According to the WHO, there were\u00a0868 global cases<\/a>\u00a0of H5N1 in humans between January 2003 and November 2022, 457 of which were fatal. Currently, a massive outbreak of bird flu is taking place around the world. The United States is experiencing the\u00a0worst avian flu outbreak in its history<\/a>, with the virus directly or indirectly leading to 58 million bird deaths in the past year, per\u00a0Fortune<\/em>. Europe is also experiencing its most severe outbreak, according to the AFP. <\/p>\n\n\n\n

\u201cWith high levels of transmission we are seeing unprecedented numbers of dead birds and outbreaks,\u201d Michelle Wille<\/a>, a bird flu researcher at the University of Sydney in Australia, tells the Sydney Morning Herald<\/em><\/a>\u2019sLiam Mannix.<\/p>\n\n\n\n

H5N1 doesn\u2019t tend to infect mammals, because they have fewer of the receptors in their upper airways that the virus binds to.<\/p>\n\n\n\n

But during this year\u2019s outbreak, foxes, raccoons,\u00a0bears<\/a>\u00a0and other mammals have caught the virus. In the U.S., mammalian infections have been detected in nine different states, according to\u00a0USA Today<\/em><\/a>\u2019s Adrianna Rodriguez. In Peru,\u00a0at least 585 sea lions<\/a>\u00a0have been found dead, likely due to bird flu. Other infected animals include dolphins and opossums, per\u00a0Fortune<\/em>.<\/p>\n\n\n\n

Most of these cases are probably caused by a mammal eating an infected bird, J\u00fcrgen Richt<\/a>, who studies avian flu at Kansas State University, tells USA Today. <\/em>But in a paper published in January in the journal Eurosurveillance<\/em><\/a>, researchers document evidence that the virus might have spread between minks on a farm in Spain last October. Genetic sequencing revealed a genetic change known to make some influenza viruses more capable of reproducing in mammals, writes Nature News<\/em><\/a>\u2019 Saima May Sidik.<\/p>\n\n\n\n

The mink outbreak \u201cconfirmed a fear that I had\u201d that bird flu could spread efficiently in mammals,\u00a0Thijs Kuiken<\/a>, a veterinary pathologist at Erasmus University Medical Center in the Netherlands, tells the\u00a0Times<\/em>.<\/p>\n\n\n\n

\u201cWe\u2019ve never seen mammal-to-mammal transmission, ever. It has never happened,\u201d Wille says to the Sydney Morning Herald<\/em>. \u201cNow it\u2019s no longer just a hypothetical. Now we\u2019ve actually seen it happen.\u201d<\/p>\n\n\n\n

Experts say this development is not a cause for alarm. \u201cIt\u2019s not, in my mind, a particularly worrisome situation for human health,\u201d Jim Lowe<\/a>, a veterinarian at the University of Illinois at Urbana-Champaign, tells the Times<\/em>. \u201cObviously it\u2019s not very good for the mink.\u201d<\/p>\n\n\n\n

The tightly packed, caged minks could have transmitted H5N1 due to their conditions rather than a fundamental change in the virus, Frank Wong<\/a>, a bird flu expert at Australia\u2019s Commonwealth Scientific and Industrial Research Organization, tells the Sydney Morning Herald. <\/em>\u201cIt\u2019s still a bird-adapted virus.\u201d<\/p>\n\n\n\n

But evidence of spread between mammals is also a warning sign, others say. \u201cThis outbreak signals the very real potential for the emergence of mammal-to-mammal transmission,\u201d Wille told the CBC News<\/a>\u2019 Lauren Pelley in an email.<\/p>\n\n\n\n

\u201cWe need to be vigilant to make sure that spread in animals is contained,\u201d Briand tells the AFP. \u201cThe more the virus circulates in animals, the higher is the risk for humans as well.\u201d<\/p>\n\n\n\n

<\/p>\n<\/div><\/div>","protected":false},"excerpt":{"rendered":"

(Smithsonian Magazine) Amid a global bird die-off from avian flu, officials have also noticed the deadly virus strain, called H5N1, infecting a growing number of mammals. This week, the World Health Organization (WHO) urged authorities to remain vigilant\u2014but not panic\u2014about the virus\u2019s potential risk to humans. \u201cThe recent spillover to mammals needs to be monitored […]<\/p>\n","protected":false},"author":11,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[37],"tags":[],"class_list":["post-2536","post","type-post","status-publish","format-standard","hentry","category-avian-influenza"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.unmc.edu\/healthsecurity\/transmission\/wp-json\/wp\/v2\/posts\/2536","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.unmc.edu\/healthsecurity\/transmission\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.unmc.edu\/healthsecurity\/transmission\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.unmc.edu\/healthsecurity\/transmission\/wp-json\/wp\/v2\/users\/11"}],"replies":[{"embeddable":true,"href":"https:\/\/www.unmc.edu\/healthsecurity\/transmission\/wp-json\/wp\/v2\/comments?post=2536"}],"version-history":[{"count":1,"href":"https:\/\/www.unmc.edu\/healthsecurity\/transmission\/wp-json\/wp\/v2\/posts\/2536\/revisions"}],"predecessor-version":[{"id":2537,"href":"https:\/\/www.unmc.edu\/healthsecurity\/transmission\/wp-json\/wp\/v2\/posts\/2536\/revisions\/2537"}],"wp:attachment":[{"href":"https:\/\/www.unmc.edu\/healthsecurity\/transmission\/wp-json\/wp\/v2\/media?parent=2536"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.unmc.edu\/healthsecurity\/transmission\/wp-json\/wp\/v2\/categories?post=2536"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.unmc.edu\/healthsecurity\/transmission\/wp-json\/wp\/v2\/tags?post=2536"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}