Since the beginning of 2025, commercial poultry flocks in the states of Delaware, Michigan and California have been affected by highly pathogenic avian influenza (HPAI), according to the United States Department of Agriculture (USDA) Animal and Plant Health Inspection Service (APHIS).
California
The first instance of HPAI in a commercial operation in 2025 was confirmed on January 2, according to APHIS. That flock was in Stanislaus County, California, and involved 75,200 commercial laying hens.
Also in Stanislaus County, HPAI was confirmed on January 3 in a commercial broiler flock. However, information regarding the size of that flock has not yet been released.
California’s third flock to be struck by HPAI in 2025 was a commercial upland gamebird flock in Butte County. In that situation, 44,700 gamebirds that were being raised for release were affected.
Delaware
On January 4, the presence of HPAI was confirmed in a commercial broiler flock in Kent County, Delaware. There were 125,000 broilers involved.
The Delaware Department of Agriculture last week reported this as a presumed-positive case.
Prior to now, Delaware had not had any incidence of HPAI in commercial poultry since March 2022. In that instance, it was also a commercial broiler flock in Kent County that was affected. Delaware had three commercial flocks affected by HPAI in 2022.
Michigan
HPAI was confirmed in two commercial meat turkey flocks in Ottawa County, Michigan, on January 3.
One of the flocks included 47,000 turkeys and the other had 55,200 turkeys.
Since December 23, 2024, Ottawa County has lost six commercial meat turkey flocks to HPAI.
Indiana
The Indiana State Board of Animal Health (BOAH) reported that it is responding to an HPAI situation in Jay County, involving a flock of 20,560 commercial turkeys.
BOAH did not state whether it was a confirmed positive or presumed positive case, but it did reveal that the farm has been quarantined. A 10-kilometer control area and a 20-kilometer surveillance zone have been put in place. Both areas include portions of Jay and Adams counties.
The last time HPAI was confirmed in a commercial poultry flock in Indiana was January 2024.
British Columbia and Ontario
The Canadian Food Inspection Agency (CFIA) has reported the presence of HPAI in commercial poultry operations in two provinces.
HPAI confirmed on January 4 that a commercial flock in Abbotsford, British Colombia, had been affected by the virus. The day before that, HPAI was confirmed in a commercial flock in North Middlesex, Ontario.
Further details concerning these flocks has not yet been released.
Canada has now had three commercial flocks struck by HPAI in 2025. The country’s first case was confirmed on January 1, with that incident also occurring in Abbotsford.
View our continuing coverage of the global avian influenza situation.
To learn more about HPAI cases in commercial poultry flocks in the United States, Mexico and Canada, see an interactive map on WATTPoultry.com.
