Highly pathogenic avian influenza (HPAI) struck a large commercial flock last week in Washington state.
The highly contagious virus spreads rapidly in poultry environments, causing severe illness or death among infected birds or animals. There is little to no risk to the public. Although this is the first commercial detection in Washington, there have been more than 250 commercial flock detections in two dozen states across the country since the beginning of the outbreak in February of 2022.
The large operation reported high numbers of sudden death in their chickens in a single barn at one of their farms to Washington State Department of Agriculture (WSDA) officials last week. Other birds were lethargic and showing additional signs of illness; prompting an investigation by state and federal veterinarians.
The Washington Animal Disease and Diagnostic Laboratory (WADDL) received samples the same day and reported ‘non-negative’ results late Friday afternoon. State officials label “non-negative” results as “presumptive positive” until confirmatory results are in. Officials expect to receive National Veterinary Services Laboratories (NVSL) confirmatory results this week.
State officials quarantined the affected premises to prevent the spread of disease. Rapid, humane, euthanasia of all birds on the premises is critical to contain the outbreak. Poultry products from the flock will not enter the food supply system.
With 37 flocks (36 domestic and one commercial) infected this year, WSDA Avian Health Program Lead and Commercial flock liaison, Dr. Dana Dobbs urges bird owners, commercial and domestic, to continue their dedication to enhanced biosecurity efforts especially with increasing detections in migrating waterfowl.
“The ongoing detections of avian influenza in our domestic flocks, commercial flocks and wild birds are incredibly unfortunate,” Dr. Dobbs said. “No matter the type or size of an operation, the losses are devastating for everyone.”
With increasing detections in wild birds across the state, it is critical to remain vigilant with biosecurity. Officials say the most effective mitigation tactic is avoiding contact with wild waterfowl, especially migrating waterfowl that reside in Washington throughout the winter.
“There is clear evidence that viral loads are high in wild birds and the environment,” Dr. Dobbs added. “Recent large die offs in geese across the state increase the risk to our domestic flocks for the unforeseeable future.”
After a commercial detection
State and federal animal health officials monitor flocks within a 10-kilometer area around the infected site for HPAI symptoms. Commercial flocks in that zone are required to monitor flock health very closely, with regular surveillance testing. They must also request permits from WSDA to move safe products out of or into the zone. Domestic flock owners in a control area are encouraged to self-report any illness or dead losses of their birds to WSDA using the online surveillance self-reporting tool.
What can the public do?
WSDA provides resources for flock owners to learn about bird flu and protect their flocks, including a bird flu webpage, an interactive map, frequently asked questions, a Facebook group, and biosecurity precautions when resuming exhibitions.
If a flock experiences sudden death or illness of multiple birds, use the new online reporting tool or call WSDA’s Sick Bird Hotline at 1-800-606-3056. Birds that have already died should be double-bagged and kept in a cooler on ice until WSDA veterinarians can arrange for sampling.
Sick or dead wild birds should not be touched or moved and can be reported using the Washington Department of Fish and Wildlife’s online reporting tool.
Posted December 16, 2022