It's Avian Influenza Season, Too

Flu season is upon us and it’s not just restricted to humans. Highly pathogenic avian influenza (HPAI), also known as avian influenza or bird flu, is a spreadable virus that affects wild birds, poultry, livestock, pets and, in rare cases, humans.

The Animal and Plant Health Inspection Service (APHIS) confirmed the current strain of the virus, H5N1, in 2022 in the U.S. about three months after the virus had been detected in one of Canada’s eastern provinces. APHIS, along with state and county organizations, have been working to respond to and mitigate the impacts of the virus, especially on the poultry industry.

“Avian influenza has been detected in 153 wild bird species across the United States,” said Molly Honea, communications coordinator for Think Wild, Bend’s nonprofit wildlife hospital. Over 10,000 cases of confirmed avian influenza have been recorded in the U.S.

Think Wild is seeing an uptick in calls to its wildlife hotline of suspected bird flu cases, so staff is following protocols when admitting a wildlife patient to the hospital, but also providing guidelines for public safety, as well.

“Think Wild always maintains strict biosecurity measures, but we implemented additional HPAI-specific protocols when it was first detected in Oregon in 2022 to mitigate potential spread,” said Dr. Laura Acevedo, Think Wild’s veterinarian. “Our protocols include immediate diagnostics for sick birds, comprehensive protective equipment for staff and rigorous cleaning procedures with EPA-registered disinfectants. These guidelines are of utmost importance to protect the patients in our care, as well as our staff and volunteers.”

HPAI has its origins in wild bird populations, hence the “avian” title of the virus. Wild birds, such as waterfowl, raptors and scavenging birds, are hit hardest as the virus spreads through body fluids or ingesting feces. Detections of the virus in wild bird populations is often higher during the spring and fall migrations, as birds spread the virus to new areas and other flocks.

The current stain of the virus H5N1 is often fatal to chickens and turkeys, and has greater impacts in the poultry industry as flocks showing signs of the virus are often destroyed to contain the spread of this virus.

If you like to geek out on science a bit, according to APHIS, the virus type H5N1 is derived from the combination of two groups of proteins that form on the outer surface of the virus — hemagglutinin or H proteins, of which there are 16 (H1-H16), and neuraminidase or N proteins, of which there are nine (N1-N9). Imagine a pin cushion full of pins. The “pins” are the proteins of the virus “cushion.” The H protein acts by attaching to and entering a cell, where the virus takes over and infects the cell and replicates itself. The N protein enables the newly created viruses to escape the host cell and eventually infect other cells. Without each protein, the viral infection would not happen.

Though the risk to humans is extremely low, the first recorded human fatality attributed to the current strain of the virus H5N1 occurred recently in Louisiana.

Owners of backyard flocks should embrace biosecurity measures to limit wildlife from spreading the virus to their poultry and preventing the virus’ spread to other areas.

Signs to look for are: loss of energy or appetite, misshapen eggs, swelling in the face, nasal discharge, incoordination or diarrhea. Biosecurity measures include protecting flocks from exposure to wild birds or ponds that may be contaminated by wild birds, cleaning and disinfecting equipment, changing and cleaning footwear and clothing after visiting a flock, keeping pets away from domestic fowl production areas and reporting any diseases, whether it’s avian flu or salmonella, to state health officials. Backyard bird feeders are encouraged to clean and disinfect feeders and remove platform-type feeders where birds may defecate on available seed.

The U.S. has a rigorous surveillance program for monitoring and detecting avian influenza in both wild and domestic bird populations. Honea said that the Oregon Department of Agriculture (ODA) and Oregon Department of Fish and Wildlife (ODFW) have been testing birds and tracking outbreaks of the H5N1 strain of avian influenza since it was first detected in Oregon in 2022.

Honea says that Think Wild is still accepting most native birds for care and that the wildlife center is following restrictions set by ODFW to not treat any adult species of waterfowl, waterbirds or shorebirds, which can be asymptomatic carriers of the virus. Think Wild screens all wild birds for symptoms of avian influenza, and sick birds are quarantined from other patients.

The public is encouraged to report any sick or dead wild birds to ODFW 866-968-2600 or Wildlife.Health@odfw.oregon.gov, contact ODA at 503-986-4711 to report sick or dead domestic birds or call Think Wild’s wildlife hotline at 541-241-8680 for questions or concerns about wild birds.

This article appears in The Source Weekly January 23, 2025.