H5N1 data update: new cases in dairy livestock and poultry

Over the past month, H5N1 infection cases have been confirmed in three dairy herds: two in Texas and one in Utah. The situation in the industrial poultry sector is characterized by more significant losses. A large outbreak was recorded in Edmunds County, South Dakota, where 29,700 poultry were affected, and an outbreak involving 2,800 individuals was identified in Brule County in the same state. Two more cases were confirmed in Idaho—in Ada and Canyon counties.

Data on the total number of cattle infections this year show a positive trend. To date, 85 infected herds have been confirmed, whereas last year this figure was 171, and in 2024 it reached 917 herds. Currently, no new human cases have been recorded; total statistics since February 2024 remain at 71 cases, with no human-to-human transmission identified.

Experts remind that pasteurized milk, as well as cooked eggs and poultry meat, remain safe for consumption, as pasteurization and thermal processing inactivate the virus. The primary risk remains for dairy and poultry farm workers who have direct contact with livestock animals, as well as for smallholder farmers.

Owners of private poultry yards are advised to contact state departments of agriculture if symptoms of the disease or sudden death are detected in their poultry. Contact with suspicious individuals should be avoided without the use of protective equipment, and interaction between domestic poultry and wild waterfowl species, which can be carriers of the virus, should be limited. The importance of observing biosecurity measures is especially relevant for regions with active wild bird migration.

The lack of operational updates on state information resources over the past month has made it difficult to obtain an accurate picture of the virus's spread. At this moment, no official announcements regarding changes to the reporting schedule have been received.