WASHINGTON — Over the past 30 days, Ohio has been the leading state for cases of highly pathogenic avian influenza (HPAI), according to data from the US Department of Agriculture’s Animal and Plant Health Inspection Service (APHIS). Two recent HPAI detections have added to the already extensive number of Ohio flocks affected by the disease, including one flock that involved over 3 million birds.

On Feb. 21, APHIS reported cases of HPAI in Darke County and Mercer County, Ohio. The HPAI detection in Darke County was found in a commercial egg laying flock, affecting nearly 3.1 million laying hens. The detection in Mercer County was also found in a commercial egg laying flock, which affected 84,800 birds.

Within the past month, Ohio has had 45 commercial flocks infected by the disease, leading to the culling of 8.5 million birds. The majority of those cases occurred in either Darke County or Mercer County.

Of the 10 states that have confirmed HPAI in poultry this month, Ohio is the only state to have reported double digits for the number of commercial flocks infected, save Missouri, which reported 13 cases.

Over the course of the entire outbreak, which began in February 2022, Ohio has reported 74 commercial flocks, 13 backyard flocks and a total of 24.9 million birds affected by HPAI.

In addition to the two cases reported in Ohio on Feb. 21, APHIS reported two commercial flocks in Indiana affected by the disease that same day. An infected commercial turkey flock in Washington County, Ind., involved 19,400 birds, and an infected commercial duck breeders flock in Elkhart County, Ind., involved 4,200 birds.