Highly pathogenic avian influenza has been detected on commercial farms in California and other parts of the United States. The most recent outbreak of the highly transmissible strain of bird flu began in early 2022 and has resulted in the deaths of millions of chickens and turkeys. It has also been detected in cows in the U.S., marine mammals in South America, and other species globally. The CDC has confirmed a handful of human cases in the U.S. and several cases of avian flu in cats on dairy farms.
The discovery of fragments of avian flu virus in milk sold in U.S. stores, including in about 20% of samples in initial testing across the country, suggests that the H5N1 virus may be more widespread in dairy cattle than previously realized.
A poultry expert at the UC Davis School of Veterinary Medicine (SVM) has teamed up with a geographic information systems (GIS) expert at UC Agriculture and Natural Resources (ANR) and two wildlife health experts from the UC Davis SVM Wildlife Health Center (WHC) to create a map showing the spread of highly pathogenic avian influenza (HPAI) since 2021.
