A panzootic outbreak of the highly pathogenic avian influenza virus H5N1 has spread to several continents and has been detected in milk samples from dairy cattle in the United States, spreading to 891 farms across sixteen states. The virus is primarily transmitted through milking and contaminated equipment. However, it is not a major threat to humans. Researchers at the Pirbright Institute have found that the viruses tested bind exclusively to avian-like receptors and have a high membrane fusion pH, suggesting that they are unlikely to transmit efficiently between humans. The authors emphasize the importance of continued surveillance and risk assessment to mitigate the impact of the virus on public health and agriculture.