November 12, 2025

Following an investigation by the Michigan Department of Agriculture and Rural Development (MDARD), the Michigan State University Veterinary Diagnostic Laboratory has detected the presence of highly pathogenic avian influenza (HPAI) in three commercial flocks from Ottawa County, one backyard flock in Monroe County, and a backyard flock in St. Clair County. Since the virus was first found in Michigan in 2022, these latest detections bring the total number of HPAI cases in poultry from an Ottawa County flock to 15. For poultry cases in 2025, there have been 10 cases of HPAI in Ottawa County, four cases in Monroe County, and one in St. Clair County. Farmers and producers of all sizes need to continue implementing and adhering to biosecurity measures and using personal protective equipment (PPE) continue to be vital in helping ensure the health of Michigan’s domestic animals and the general public.

HPAI is a highly contagious virus that can be spread in various ways from flock to flock, including by wild birds, through contact with infected animals, by equipment, and on the clothing and shoes of caretakers.