The United States Department of Agriculture’s (USDA) Animal and Plant Health Inspection Service (APHIS) has confirmed the presence of highly pathogenic H5N2 avian influenza (HPAI) in a commercial layer flock in Jefferson County, Wisconsin.

The flock of 200,000 chickens is located within the Mississippi flyway where this strain of avian influenza has previously been identified.

Samples from the chicken flock, which experienced increased mortality, were tested at the Wisconsin Veterinary Diagnostic Laboratory and the APHIS National Veterinary Services Laboratories (NVSL) in Ames, Iowa confirmed the findings.

APHIS is working closely with the Wisconsin Department of Agriculture, Trade and Consumer Protection on a joint incident response.

State officials quarantined the premises and birds on the property will be depopulated to prevent the spread of the disease. Birds from the flock will not enter the food system.

Centers for Disease Control and Prevention (CDC) considers the risk to people from these HPAI H5 infections in wild birds, backyard flocks and commercial poultry, to be low. No human infections with the virus have been detected at this time.

The majority of the outbreaks of H5N2 highly pathogenic avian flu in the US this year have involved turkeys; the only chickens to have been involved were in backyard flocks.