H5N1 genotype D1.1 in a dairy cattle in Maricopa County
15 February, 2025
The Arizona Department of Agriculture (AZDA), in collaboration with the United States Department of Agriculture (USDA), has confirmed the first detection of H5N1 avian influenza in milk produced by a dairy herd in Maricopa County, Arizona.
The dairy herd that tested positive for the D1.1 H5N1 genotype is currently under quarantine; however, the cattle are exhibiting no symptoms at this time.
This detection resulted from AZDA's implementation of the National Milk Testing Strategy, which was initiated in January and focuses on farm-level bulk tank testing. This case of avian influenza is consistent with the D1.1 genotype and is unrelated to the recent detection of this virus in Nevada.
