The U.S. Department of Agriculture’s Animal & Plant Health Inspection Service (APHIS) has confirmed highly pathogenic avian influenza (HPAI) in two large egg laying operations in Washington and Utah. The cases mark the first commercial case for Utah in just over a year and the first commercial case for Washington in nearly two years.

Depopulation is underway at the table egg laying egg laying operation of 839,700 birds in Franklin County, Wash., and a table egg laying operation of 1.85 million birds in Cache County, Utah.

Utah case

Utah State Veterinarian Dr. Daniel Christensen said the state veterinarian’s office was recently notified of symptomatic birds in Cache County. The agency’s team was immediately dispatched to assess the situation, and proper steps are now being taken to prevent further spread of the disease.

Utah Department of Agriculture & Food (UDAF) officials are working closely with APHIS on the incident response, and the area in which the birds were located has been quarantined.

As part of existing avian influenza response plans, UDAF and its federal partners are working jointly on additional surveillance and testing in areas around the affected flock. 

“Poultry owners should vigilantly watch their flocks for symptoms of HPAI, which include high death loss among flocks, nasal discharge, decreased appetite or water consumption, and lack of coordination in birds,” the agency said.

Washington case

In the Washington case, the Washington State Department of Agriculture (WSDA) said high numbers of sudden death in chickens were reported on Oct. 11 at one of the Franklin County commercial farm's locations. Other birds were lethargic and showing additional signs of illness, prompting an investigation by state and federal veterinarians.

The Washington Animal Disease & Diagnostic Laboratory received samples and reported “non-negative” results late Friday evening (state officials label “non-negative” results as “presumptive positive” until confirmatory results are in). The results were confirmed by the National Veterinary Services Laboratories (NVSL) late Tuesday, Oct. 15.

State officials quarantined the affected premises to prevent the spread of disease. WSDA avian health program lead and commercial flock liaison Dr. Dana Dobbs is urging bird owners, both commercial and domestic, to continue enhanced biosecurity efforts, especially with increasing detections in migrating waterfowl.

The most recent commercial case prior to these two was reported one month ago in Merced County, Calif., in a turkey flock of 64,800 birds. USDA data shows that since the initial outbreak in February 2022, 103.47 million birds have been affected by the virus. Of a total of 1,180 flocks affected, 511 of those have been commercial.

Michigan dairy herd tests positive

Michigan Department of Agriculture & Rural Development (MDARD) Director Tim Boring announced this week the detection of HPAI in a dairy herd from Clinton County, bringing the total number of affected dairy herds in Michigan to 30. Testing through the Michigan State University Veterinary Diagnostic Laboratory initially detected this case. Samples have been sent to USDA's NVSL for additional confirmatory testing.

Regardless of the species, MDARD said biosecurity remains the best tool available to combat HPAI.

On May 1, 2024, director Boring issued the Determination of Extraordinary Emergency HPAI Risk Reduction & Response Order. In addition to other protocols, the order requires all dairy operations in Michigan to adopt enhanced biosecurity measures, collectively reducing the risk of introducing this virus onto farms. The order also prohibits the exhibition of all lactating dairy cattle and those in the last two months of pregnancy until there are no new cases of HPAI in Michigan dairy cattle for at least 60 consecutive days. No dairy cattle of any age from an infected premises may be exhibited until further notice.

As part of the disease response, MDARD said it is working with the herd veterinarian to monitor the health of the animals and conduct trace investigations. Additionally, MDARD and various federal and state partners offer personal protective equipment at the request of dairy operations. The department continues to diligently work with local, state, and federal partners to quickly respond to reports of HPAI to mitigate the spread of the disease and provide outreach.

Meanwhile, the California Department of Food and Agriculture (CDFA) announced this week that avian flu has been confirmed in 105 dairies in central California. CDFA said it has implemented a surveillance strategy with the goal of finding affected farms as early as possible. Early detection provides the opportunity to work with farms to quickly implement enhanced biosecurity, cow care, and employee protection, the agency said.