Science High-pathogenicity avian influenza subtype H5N1 is now present throughout the US, and possibly beyond. More cattle infections elevate the risk of the virus evolving the capacity to transmit between humans, potentially with high fatality rates. Nguyen et al. show that from a single transmission event from a wild bird to dairy cattle in December 2023, there has been cattle-to-poultry, cattle-to-peridomestic bird, and cattle-to-other mammal transmission. The movement of asymptomatic dairy cattle has facilitated the rapid dissemination of H5N1 from Texas across the US. Evolution within cattle, assessed using deep-sequencing data, has detected low-frequency sequence variants that had previously been associated with mammalian adaptation and transmission efficiency.
Emergence and interstate spread of highly pathogenic avian influenza A(H5N1) in dairy cattle in the United States
- Published Apr 30, 2025