Avian flu detected in Alaskan wild birds and a fox

By Megan Gannon
North America is currently experiencing one of the largest recorded outbreaks of a highly infectious and deadly strain of avian influenza virus, also known as the H5N1flu. More than 38 million domestic birds have been culled in the U.S. and Canada, but what makes this outbreak unprecedented is its toll on wild birds.
That’s what an audience composed of local subsistence hunters, scientists, recreational birders and other Alaskans heard during last week’s Strait Science presentation organized by UAF Northwest Campus. The lecture was timely as several cases of highly pathogenic avian influenza have been documented in wild birds in Alaska. Residents of the Bering Strait region are being told to look out for sick birds—and possibly mammals, too. In at least one case, in Unalaska, the virus was detected in a red fox and pet owners have been warned to keep their animals away from dead birds.
The current outbreak, which struck North America in late 2021, is “only the second outbreak to affect wild birds in the U.S. and Canada,” said the first speaker, Andy Ramey, a research wildlife geneticist with the U.S. Geological Survey in Anchorage. “The number of wild bird detections during the past six months is more than 15 times greater than the total number of detections of highly pathogenic avian influenza and wild birds in Canada and the United States during all prior outbreaks,” Ramey said.
Ramey offered extensive background information on the virus to help put the current outbreak in context.  
He explained that there are some types of bird flu that naturally occur in wild birds, and birds often appear perfectly healthy when infected with these strains.
“Not all bird flu makes birds sick or causes them to die,” Ramey said. “Sometimes bird flu viruses that naturally occur in wild birds spillover into domestic poultry. Oftentimes, poultry infected by these types of viruses also appear to be perfectly healthy.”
The small portion of bird flu viruses that do cause disease death among chickens and turkeys are called highly pathogenic avian influenza viruses, he said. “The tendency for viruses to cause serious disease and death among birds, or to become highly pathogenic, typically only occurs after viruses are introduced in the poultry,” Ramey said.
When those highly pathogenic strains spread, they can result in the death and destruction of large numbers of domestic birds. To date, more than 350 poultry premises have been affected in the United States, with more than 38 million birds culled. There have also been more than 1,600 detections of the disease in wild birds in the United States and Canada, most of which came from visibly sick or dead birds.
The spread of highly pathogenic avian influenza from poultry to wild birds has only become common within the past 20 years, Ramey said. Prior to 2002, there had been only one outbreak of highly pathogenic avian influenza globally, which occurred in South Africa in 1961. “Things have changed; outbreaks in wild birds have become more common and more geographically widespread,” especially after 2005, Ramey explained.
Some birds, especially waterfowl like mallards and pintails, can carry the virus while still appearing healthy, Ramey said. Other birds, especially raptors like eagles, hawks, falcons and owls, seem to be most adversely affected by the current outbreak. Signs of disease in wild birds may include lack of coordination, stumbling, inability to stand upright, inability to fly, swimming in circles, a twisted neck or paralysis.
Robb Kaler, a wildlife biologist with the U.S. Fish and Wildlife Service’s migratory bird management department based in Anchorage, spoke next. The focus of his talk was not highly pathogenic avian influenza but another troubling trend among wild birds: Seabird die-off events.
“We count seabirds as indicators of the status of the marine ecosystem, and the health of that [ecosystem], owing to the fact that seabirds live the majority of their lives at sea,” Kaler said. “They only come to shore to breed, and that provides a chance to monitor the long-term population trends.”
Historically, die-offs used to be rare, and associated with strong El Niño events or disease, but since 2015, die-offs have become annual occurrences, mostly in the Bering Strait, Bering Sea and the Aleutians, Kaler said.
He also told the audience that when there are die-offs, every dead bird that is received by the National Wildlife Health Center is swabbed and tested for avian influenza. Kaler emphasized that highly pathogenic avian influenza is not typically found among seabirds.
The first question from the audience came from a caller who joined the Zoom from Little Diomede, an island full of seabird colonies of species like crested auklets, least auklets, puffins, kittiwakes and cormorants. Birds on the island are used for their meat and eggs by subsistence hunters. “Are we in danger?” the caller asked. “Are we safe? Are we safe to eat the birds which we consume every summer?”
As neither speaker was specialized in human health, they could not give medical advice and deferred to the guidance from the Centers for Disease Control and Prevention. Currently, the CDC says the virus poses low risk to humans. So far one case of the virus has been detected in humans, in poultry worker in Colorado who was in close contact with an infected commercial flock, albeit in personal protective gear. He was largely asymptomatic, reporting only fatigue after testing positive. The Strait Science audience was reminded to avoid harvesting or handling birds that appear sick, and to document and report any cases of strangely behaving or dead birds.
“If you can take photos or make a short video, this is also extremely helpful,” Ramey said. “Please do not pick up carcasses, move dead birds or try to capture or handle sick birds. Your observations and reports are currently the best way to help document the effects of highly pathogenic avian influenza during the outbreak.”
Another participant wanted to know how common or rare it is for the disease to jump into mammals. Several cases have now been documented in foxes and skunks in North America.

“This spillover between birds and mammals is not rare,” Ramey said. “It does occur. But when viruses spill over into mammals, there tends to be a heightened concern about further spread in mammals. I think what’s going on is not without precedent. It’s not unheard of. But it’s also not extremely common. And it’s something that I think many different agencies and many different people are keeping careful watch [of], to see what, if anything, comes next.”
One audience member joined from Unalaska and said she had reported a sick eagle there a few weeks ago. She wanted to know if recording and calling in such incidents was all she could do.
“I do think in order to maintain health and safety for the general public that it’s probably best to have trained personnel respond to these events,” Ramey said. “And I think that’s why guidance has been what it is.”
Kaler added that since Alaska is such a huge state, these opportunistic reports from the public are crucial for monitoring the situation. “We really are so indebted to community members for providing that information,” he said.
To report unusual observations and concerns about birds, call the U.S. Fish and Wildlife Service Alaska Sick/Dead Bird Hotline at 1-866-527-3358. The Alaska Department of Fish and Game Wildlife Health Reporting can be reached via email at dfg.dwc.vet@alaska.gov. Reports can also be posted to the Local Environmental Observer Network, www.leonetwork.org or locally to Gay Sheffield, UAF Alaska Sea Grant at (907) 434-1149.

 

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