Bird flu detected at another Jefferson County poultry facility

Another commercial poultry facility in Jefferson County must cull more than half a million birds due to highly pathogenic avian influenza. 

The Wisconsin Department of Agriculture, Trade and Consumer Protection on Thursday announced the detection of the H5N1 virus. The facility is owned by Daybreak Foods and located in the township of Palmyra. The cause of the infection is under investigation.

Regulators are limiting movement of poultry within a 10-kilometer area around the infected facility, which has been quarantined. Birds from the flock will not enter the general food supply. 

The Wisconsin Department of Health Services and Jefferson County Public Health are monitoring farm workers for signs of the virus. The risk to the public remains low.

It’s the second detection of bird flu at the company’s facilities within the last week. The virus previously forced Daybreak to cull more than 3 million birds at another site in the town of Palmyra. Daybreak Foods is the nation’s fourth-largest egg producer, with 17 million hens across their farms in the Midwest, according to the company’s website.

The H5N1 virus  was first detected in Wisconsin in 2022. The disease continues to circulate in both wild and domestic birds. The virus is highly contagious. It can spread by contact with infected birds, their droppings and through clothing worn by those working with affected animals.

The virus has not been detected in dairy cows in Wisconsin. The state began mandatory milk testing for avian flu earlier this year. Wisconsin has collected more than 18,000 milk samples from nearly all the state’s licensed dairies with no signs of the virus.

State ag officials urge livestock owners to protect their flocks by taking biosecurity measures that include washing hands, disinfecting equipment and keeping birds indoors when possible.

In the last 30 days, outbreaks have been confirmed at 27 poultry flocks in the country, affecting 3.8 million birds, according to the USDA. The Centers for Disease Control and Prevention has confirmed 70 cases of people who have contracted the virus and one death. Wisconsin has had at least one human case of avian flu since 2022. 

Wisconsin Public Radio, © Copyright 2025, Board of Regents of the University of Wisconsin System and Wisconsin Educational Communications Board.