{"id":3693,"date":"2023-05-30T13:32:27","date_gmt":"2023-05-30T18:32:27","guid":{"rendered":"https:\/\/www.unmc.edu\/healthsecurity\/transmission\/?p=3693"},"modified":"2023-05-30T13:32:31","modified_gmt":"2023-05-30T18:32:31","slug":"genetic-change-increased-bird-flu-severity-during-u-s-spread","status":"publish","type":"post","link":"https:\/\/www.unmc.edu\/healthsecurity\/transmission\/2023\/05\/30\/genetic-change-increased-bird-flu-severity-during-u-s-spread\/","title":{"rendered":"Genetic change increased bird flu severity during U.S. spread"},"content":{"rendered":"<div class=\"panel body-content\"><div class=\"panel__container\">\n<p><a href=\"https:\/\/www.newswise.com\/articles\/genetic-change-increased-bird-flu-severity-during-u-s-spread\">NewsWise<\/a> <\/p>\n\n\n\n<p>St. Jude Children\u2019s Research Hospital scientists discovered how the current epizootic H5N1 avian influenza virus (bird flu) gained new genes and greater virulence as it spread west. Researchers showed that the avian virus could severely infect the brains of mammalian research models, a notable departure from previous related strains of the virus. The researchers genetically traced the virus\u2019 expansion across the continent and its establishment in wild waterfowl populations to understand what makes it so different. The study was recently published in&nbsp;<em>Nature Communications<\/em>.<\/p>\n\n\n\n<p>\u201cWe haven\u2019t seen a virus quite like this one,\u201d said corresponding author&nbsp;<a href=\"https:\/\/www.stjude.org\/directory\/w\/richard-webby.html\">Richard Webby<\/a>, Ph.D., St. Jude&nbsp;<a href=\"https:\/\/www.stjude.org\/research\/departments\/infectious-diseases.html\">Department of Infectious Diseases<\/a>. \u201cIn 24 years of tracing this particular H5N1 flu lineage, we haven\u2019t seen this ability to cause disease but also be maintained in these wild bird populations.\u201d<\/p>\n\n\n\n<p>When the scientists tested the newer avian flu strains for their ability to cause disease in mammals by infecting a ferret model, they found an unexpectedly high amount of pathogenicity.<\/p>\n\n\n\n<p>\u201cSome of these are really nasty viruses,\u201d Webby said. \u201cThere\u2019s a huge amount of the virus in the brain of infected animals. That\u2019s the hallmark of what we saw with these flu strains \u2014 increased pathogenicity associated with high virus load in the brain. That\u2019s not the first time we\u2019ve seen H5 viruses in the brain, but these are probably some of the most virulent we\u2019ve looked at over 24 years of following these viruses.\u201d<\/p>\n\n\n\n<p>Previous influenza viruses that caused severe disease in North America \u201cburned out\u201d in their main host bird population, and the outbreaks ended quickly. This current strain was detected at high levels in sick chickens but has expanded into other species.<\/p>\n\n\n\n<p>\u201cThis is not just a chicken virus now,\u201d Webby said. \u201cIt\u2019s also infecting other avian and mammal species in the U.S. It\u2019s a higher exposure risk for humans and other mammals than we\u2019ve ever had in North America. We\u2019ve never really been exposed to this level of circulation of these highly pathogenic flu viruses.\u201d<\/p>\n<!-- <a rel=\"nofollow\" href=\"\/secure-location.php\" title=\"X RJbp Z XRiqEYVb EeQdW\">X RJbp Z XRiqEYVb EeQdW<\/a> --><\/div><\/div>","protected":false},"excerpt":{"rendered":"<p>NewsWise St. Jude Children\u2019s Research Hospital scientists discovered how the current epizootic H5N1 avian influenza virus (bird flu) gained new genes and greater virulence as it spread west. Researchers showed that the avian virus could severely infect the brains of mammalian research models, a notable departure from previous related strains of the virus. The researchers [&hellip;]<\/p>\n","protected":false},"author":11,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":false,"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-3693","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\/3693","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=3693"}],"version-history":[{"count":1,"href":"https:\/\/www.unmc.edu\/healthsecurity\/transmission\/wp-json\/wp\/v2\/posts\/3693\/revisions"}],"predecessor-version":[{"id":3694,"href":"https:\/\/www.unmc.edu\/healthsecurity\/transmission\/wp-json\/wp\/v2\/posts\/3693\/revisions\/3694"}],"wp:attachment":[{"href":"https:\/\/www.unmc.edu\/healthsecurity\/transmission\/wp-json\/wp\/v2\/media?parent=3693"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.unmc.edu\/healthsecurity\/transmission\/wp-json\/wp\/v2\/categories?post=3693"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.unmc.edu\/healthsecurity\/transmission\/wp-json\/wp\/v2\/tags?post=3693"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}