USDA continues investigation of avian influenza in dairy cattle
Studies on its spread and impact on human health are ongoing
3 January 2025
2 minute read
By: The US Department of Agriculture (USDA), the US Food and Drug Administration (FDA), and the Centers for Disease Control and Prevention (CDC), along with state partners, continue to investigate an outbreak of Avian Influenza A (H5N1) impacting poultry, dairy cows, and people in multiple states, according to a recent news release from the FDA.
The responsibility of the FDA is to protect the public health by ensuring the safety of the milk, dairy products, and animal feed supply. The US Department of Agriculture’s Animal and Plant Health Inspection Service is leading the response from the animal health perspective while coordinating closely with the FDA and with the Centers for Disease Control and Prevention.
Status of the milk supply
After the first detection of HPAI H5N1 in dairy cattle in March 2024, the FDA has engaged in research and other efforts with industry, federal, and state partners to ensure the continued effectiveness of the federal-state milk safety system.
Nearly all (99%) of the commercial milk supply that is produced on dairy farms in the US comes from farms that participate in the Grade A Milk Safety Program and follow the Pasteurised Milk Ordinance (PMO), which includes controls that help ensure the safety of dairy products. Pasteurisation and diversion or destruction of abnormal milk are two important measures that are part of the federal-state milk safety system.
The process of pasteurization has helped to ensure the health of the American public for more than 100 years. Pasteurization kills harmful bacteria and viruses by heating milk to a specific temperature over time. Even if the virus is detected in raw milk, the current pasteurisation process (HTST – High Temperature, Short Time) will inactivate the virus.
On December 23, 2024, the FDA began a domestic sampling assignment to collect and test aged raw cow’s milk cheese for Highly Pathogenic Avian Influenza (H5N1). Research and studies are ongoing.
