Avian influenza: common questions and answers

Originally published June 16, 2022. Updates to this blog:
- Jan. 24, 2023- information added on a bobcat that tested positive for HPAI
- Dec. 16, 2022- information added on a raccoon that tested positive for HPAI.
- Dec. 8, 2022- a
statement added on bird flu around Skagit Bay
- July 15, 2022- information added regarding a raccoon that tested positive for HPAI
- Nov. 3, 2023- information added regarding seals testing positive for HPAI.

Please report sick or dead wild birds suspected of having avian influenza

In August of 2023, NOAA Fisheries confirmed that three adult harbor seals in Puget Sound tested positive for the Highly Pathogenic Avian Influenza (HPAI) H5N1 strain. It is believed that the virus was transmitted to the seals on Rat Island and Marrowstone Island from seabirds involved in an HPAI outbreak that resulted in the death of approximately 1,700 birds. This marked the first incidence of HPAI in marine mammals on the West Coast.

The tern colony on Rat Island that experienced an HPAI outbreak in summer of 2023.

Other mammals have also contracted HPAI. In January of 2023, a bobcat from northeast Washington tested positive; the fourth mammal in Washington to test positive to do so since July of 2022. Three raccoons (one on Camano Island, one in Spokane County and one in the Tri Cities area) tested positive in 2022.

While this may seem alarming to some, it is not surprising that the virus is showing up in mammals. It has done so in other states as well and was not unexpected in Washington. At this time, WDW veterinarians are not worried about the impact from avian influenza to mammal populations. With just four mammals that have tested positive since July, it does not appear to be spreading from birds to other species quickly.

Following are answers to common questions regarding HPAI, the impact to wildlife, and the potential spread to domestic animals and humans, as well as what you can do to protect yourself and your animals:

What is HPAI?
Avian influenza, also known as bird flu, refers to the disease caused by infection with avian (bird) influenza (flu) Type A viruses. These viruses occur naturally among wild aquatic birds worldwide and can infect poultry and other bird and animal species. Wild aquatic birds include ducks, geese, swans, gulls and terns, and shorebirds

Avian influenza A viruses are very contagious among birds through saliva, nasal secretions, feces, and contaminated surfaces. These viruses are classified into two categories: low pathogenic avian influenza (LPAI) and highly pathogenic avian influenza (HPAI). LPAI viruses cause either no signs of disease or mild disease in chickens/poultry (such as ruffled feathers and a drop in egg production). HPAI can be transmitted to domestic birds such as chickens, ducks, and turkey and generally leads to death for these birds.

Is it common for other animals, besides birds, to catch HPAI?
In addition to the January 2023 confirmed case of HPAI in a bobcat, three raccoons tested positive in various places around the state in 2022.

These are not the first cases of HPAI in mammals. This strain has also been detected in red foxes, striped skunks, and bobcats in other states in North America. However, Washington had the first detections of H5 2.3.4.4 in raccoons in North America, and the raccoons were the first detection of HPAI in a mammal in Washington state.

While these developments may be concerning to some as they signal a spread of the HPAI virus from birds to mammals in our state, they are not completely unexpected and not something to panic about. According to the Centers for Disease Control and Prevention, as HPAI H5N1 viruses continue to evolve, other mammals may become infected.

What can be done to prevent the spread of HPAI to other wildlife species?
Humans should avoid handling sick of dead birds and should keep their pets from scavenging or interacting with dead wildlife. Practices that cause birds to congregate in large numbers such as feeding waterfowl should also be avoided.

Take special precautions to ensure that all equipment (boots, clothes, vehicles, firearms) are cleaned and disinfected to prevent spreading diseases from one area to another.

If you observe sick or dead birds, or other wildlife, please report it to WDFW’s online reporting tool.

What can be done to treat wildlife with HPAI? Is there a treatment or vaccine?
Unfortunately, treatment is not an option for wild species. Most birds that become ill with HPAI will die from the infection.

Could the spread of AI to other species potentially have a big impact on wildlife species over time?
Given what is known at this time, this is unlikely.

If wild animals can catch HPAI, can my domestic animals?
Again, given what is currently known about this strain of HPAI, this is unlikely. Still, appropriate action should be taken to reduce the potential risk to mammals such as cats and dogs, including not allowing domestic animals to scavenge sick/dead birds or other wildlife, or even interact with sick wildlife. In addition, HPAI can infect domestic chickens, ducks, turkey. If sick or dead poultry are observed, please report to the Washington Department of Agriculture.

Photo courtesy of Jillian Garrett

Can HPAI transfer to humans?
Bird flu viruses are not easily transmissible from birds to people, but without proper hygiene, or if in prolonged contact with a sick bird, the risk increases and the virus can spread to humans. While it is extremely unlikely that hunters or people feeding wild birds could contract bird flu, the following common-sense precautions are recommended to reduce the risk of contracting any wildlife disease:

· Wear disposable gloves when cleaning harvested birds or cleaning bird feeders.

· Do not harvest or handle wild birds that are obviously sick or found dead.

· Do not eat, drink, or smoke while cleaning game.

· Wash hands with soap and water or use alcohol hand sanitizer immediately after handling game or cleaning bird feeders.

· Wash tools and work surfaces used to clean game birds with soap and water, then disinfect with a 10 percent solution of chlorine bleach.

· Separate raw meat, and anything it touches, from cooked or ready-to-eat foods to avoid contamination.

· Cook game birds thoroughly. Meat should reach an internal temperature of 155 to 165 degrees Fahrenheit to kill disease organisms and parasites.

If you experience flu-like symptoms following contact with sick or dead wild birds or have concerns about potential exposure to infected birds, contact your local health department. They can provide public health recommendations and guidance on symptom monitoring and testing of people exposed to avian influenza.

Additional animal and human health and safety information regarding avian influenza is on the U.S. Department of Agriculture Animal and Plant Health Inspection Service website.

How long can the HPAI virus survive in the environment?
In the right conditions, it can survive from day to weeks but the most likely way for the virus to transfer to other birds or mammals is sick or dead birds, not from the environment.

Where does the HPAI outbreak in WA wild birds and other animals stand currently?
You can view positive detections in Washington state on the WDFW website.

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The Washington Department of Fish and Wildlife

The Washington Department of Fish and Wildlife is dedicated to preserving, protecting and perpetuating the state’s fish and wildlife resources.