The Michigan Department of Agriculture and Rural Development (MDARD) announced the second detection of highly pathogenic avian influenza (HPAI) in a commercial flock in Michigan and in Muskegon County since the disease first reached the state in 2022, according to a press release from the University of Nebraska Medical Center.

The Michigan State University Veterinary Diagnostic Laboratory confirmed an HPAI case at a commercial poultry facility in Muskegon County on Dec. 19.

In the past week, APHIS has confirmed outbreaks in eight states: California, Kansas, South Dakota, Idaho, Minnesota, Arkansas , Ohio and Oregon. 

A commercial egg operation in California lost 497,700 birds, and a commercial egg operation in Ohio lost 560,000 birds. In the previous week, an egg layer operation in California lost nearly 1.4 million birds.