Avian influenza: common questions and answers regarding transmission to mammals
Updated July 15, 2022 to reflect a second confirmed case of HPAI in a raccoon in Spokane County.
A raccoon kit (baby) found at a park in Franklin County tested positive for the highly pathogenic avian influenza (HPAI) virus H5N1 184.108.40.206 strain in June of 2022. It was one of four kits found; two were dead and two euthanized due to showing obvious signs of being sick. A gull from the same park also tested positive for HPAI. In mid-July of 2022, a second raccoon was also confirmed to have the HPAI virus, this time in Spokane County.
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. Following are answers to common questions regarding HPAI, the impact to wildlife, and the potential spread to domestic animals and humans:
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?
This is not the first case of HPAI H5 220.127.116.11 in a mammal. This strain of HPAI has also been detected in red foxes and striped skunks in North America. However, these are the first detections of H5 18.104.22.168 in raccoons in North America, and the first detection of HPAI in a mammal in Washington state.
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. 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.
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 dispose of processed bird carcasses in the field where they could be eaten by scavengers or raptors. Bag them and place in the garbage, bury, or incinerate them.
· Take special precautions to ensure that all equipment (boots, clothes, vehicles, firearms) are cleaned and disinfected to prevent the spread of diseases.
· 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.