State agriculture officials announced they have found highly pathogenic avian influenza, or HPAI, in a Benton County dairy herd, marking a new county where the virus has spread to. 

The herd has been quarantined, biosecurity measures implemented and veterinarians are treating sick cows, according to a release. Pasteurized dairy products remain safe and no shortages are expected.

“Seeing the virus move to another county is disappointing but our dairy farmers are working hard to implement their biosecurity plans, share lessons learned and help each other get through this,” said Washington State Veterinarian Amber Itle in a statement. “This isn’t new for the country, but it is new for Washington. I’ve been in awe of how hard our veterinarians and dairy farmers work together every day to keep their cows healthy, keep their workers safe and keep operating despite all the uncertainty this virus brings with it.” 

Prior to the Benton County detection announcement, HPAI had been found in 27 herds in Yakima County since early October. 

According to the Washington Department of Agriculture, HPAI can spread between dairy cattle through infected animals and contaminated milk, equipment, vehicles, clothing, footwear and other materials or people that move between farms. 

Symptoms include: 

• Changes in milk appearance (thicker, often yellowish to brown) 

• Decline in feed intake 

• Fever 

• Respiratory symptoms 

• Changes in manure 

• Steep drop in rumination and rumen motility 

Wild birds also can carry HPAI, but they are not considered the primary means by which dairy herds are infected.  

Poultry are also highly susceptible to HPAI. Other states have reported infections in commercial and backyard poultry flocks near dairy farms affected by H5N1, a form of HPAI. Poultry owners, including those who keep backyard flocks, should remain vigilant for signs of illness and practice strong biosecurity to help reduce the risk of infection.