Where does H5N1 virus in cattle and humans lead?

• The emergence of Avian Influenza H5N1 in late 2020 led to a global outbreak, causing widespread mortality among birds and infecting over 200 mammalian species, including humans.
• In March 2024, the virus was detected in cattle in the U.S., causing a drop in milk production and spreading rapidly across 14 states.
• The virus remained undetected for nearly four months before being confirmed by the USDA.
• Human infections from the outbreak in cattle were first noted in Texas in April 2024.
• Since then, 26 cases have been reported in California, Colorado, Michigan, Missouri, and Texas.
• The risk of infection with avian influenza H5N1 for humans not directly working with cattle or poultry remains low, but there has been no documented human-to-human transmission.
• The CDC suggests that the risk increases with close and prolonged exposure to infected animals or contaminated environments.
• The wastewater surveillance program in the U.S. supplements conventional surveillance methods to provide early warnings. Genomic surveillance could enable timely interventions, enhance disease monitoring, and improve preparedness by identifying potential risks early.