KANSAS CITY, MO.  — As of Oct. 20, 21 flocks tested and confirmed having highly pathogenic avian influenza (HPAI), according to the US Department of Agriculture (USDA), including commercial flocks and backyard flocks. The agency expects the number of cases to fluctuate as levels of the virus change based on wild bird movement. US poultry growers have been dealing with HPAI since 2021.

The HPAI virus has also affected other species, including cattle and humans. On Oct. 16, the Yakima Health District (YHD) confirmed a human case of avian influenza in a Yakima County, Wash., resident, who was exposed to infected dairy cattle at a dairy in the county.

“The resident has not experienced severe illness or been hospitalized,” the YHD said. “The individual is isolating at home. YHD is contacting anyone who has been in close contact with the patient to monitor for symptoms.”

YHD emphasized that the risk of avian influenza infection to the general public is low, and people at greater risk include dairy workers and others who have close or prolonged contact with infected animals or environments contaminated with the virus.

“Transmission of avian influenza between humans is extremely rare and has never been documented in the United States,” YHD said. “To ensure that human-to-human spread is not occurring, public health officials are contacting anyone who has been in close contact with the patient to monitor for symptoms.

“We are working closely with our public health partners to follow up with people who have been in close contact with this individual,” said Dave Atteberry, MD, health officer, Yakima Health District. “We want to make sure they know what symptoms to watch for and can access testing and treatment if needed.”

YHD added that the agency has been in contact with the impacted dairies to protect the health of people who may have been exposed to infected cattle since the initial detection of HPAI in Yakima County in early October when USDA and the Washington State Department of Agriculture (WSDA) confirmed the H5N1 strain in two dairy farms in Yakima County, the first known detection of HPAI in cattle in Washington state.

“Dairy cattle in a total of 19 states have been infected since the start of the outbreak in March 2024,” WSDA said. “Washington State Department of Agriculture conducted on-farm investigations, testing and gathered additional epidemiological information to better understand this detection and limit further disease spread. The two farms are under quarantine and have employed strict biosecurity measures. Veterinarians are working to treat sick cows.”

The agency noted that most cattle affected by HPAI recover in about six weeks.

“We appreciate how difficult this is for our dairy families, farmworkers and veterinarians that are working hard to keep animals safe and healthy,” said Washington State Veterinarian Amber Itle, VMD, MS. “The most important thing you can do is implement enhanced biosecurity and report symptoms immediately if animals show signs of illness.”

Affected flocks in Wisconsin, Minnesota

A case of HPAI was detected in a commercial poultry flock in Barron County, Wis., according to officials with the Wisconsin  Department of Agriculture, Trade and Consumer Protection (DATCP).

The affected premises have been quarantined to restrict movement of poultry and poultry products, DATCP said. Birds on the site were culled to prevent the spread of the disease; no infected birds will enter the food system.

“When HPAI is diagnosed in a Wisconsin poultry flock, a control area is established within a 10-km area around the infected premises, restricting movement on or off any premises with poultry,” DATCP said.

Previous HPAI detections in Wisconsin were in a backyard poultry flock in Racine County earlier in October, and a commercial flock in Barron County in September that affected more than 79,000 birds, according news reports.

And in Minnesota, the state’s Board of Animal Health reported five affected commercial flocks, four affected backyard flocks and a total of 190,960 birds affected in the last 30 days.

HPAI viruses are highly contagious and often fatal to domestic poultry and wild birds. The disease can be spread by contact with infected birds, commingling with wild birds or their droppings, equipment or clothing worn by anyone working with the animals. For this reason, DATCP urges all livestock owners to implement strong biosecurity measures to protect their flocks and herds.

Erica Shaffer is the managing editor of MEAT+POULTRY. After joining Sosland Publishing Co.in 2009, Shaffer worked as the website editor of several Sosland titles before joining MEAT+POULTRY as its digital media editor in 2012. Most recently, Shaffer served as MEAT+POULTRY’s Digital Media Senior Editor, a role she was promoted to in 2019. She writes, edits and produces website exclusive stories, images, videos and podcasts featuring leading industry figures, events and issues of interest to meat and poultry processors. Erica brings more than 20 years of experience as a journalist to the role.

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