May 10, 2024

The FDA, alongside our federal and state partners, is continuing to take a stepwise approach to our scientific analysis of commercial milk safety during the first-of-its-kind detection of HPAI H5N1 in dairy cattle. While our initial assessment of the milk safety system continues to be affirmed by sampling and testing of retail dairy products, there remain a number of collective activities being undertaken to ensure the continued effectiveness of the federal-state milk safety system. The FDA will continue to follow a sound scientific process to inform the agency’s public health decisions related to food safety.

Last week we announced preliminary results of a study of 297 retail dairy samples, which were all found to be negative for viable virus. The FDA is today announcing that all final egg inoculation tests associated with this retail sampling study have been completed and were also found to be negative for viable HPAI H5N1 virus. These confirmatory test results mark the completion of our laboratory research efforts related to these 297 retail dairy samples. Additional sampling and other surveillance activities will continue.

While our retail sampling test results to date are clear about the safety of the commercial milk supply and representative of real-world scenarios, additional scientific work is being undertaken to validate the criteria for pasteurization relative to the HPAI H5N1 virus and will include tests using pasteurization equipment typically used by milk processors. Today, we’d like to share more about our additional research efforts.

The established pasteurization process set forth in federal regulation (21 CFR 1240.61) and the Pasteurized Milk Ordinance (PMO) provides specific temperature and time requirements for effective elimination of known pathogens in the milk supply. To further validate pasteurization effectiveness against this recently detected virus, the FDA previously noted it was testing samples of pooled raw milk routed for commercial processing to characterize potential virus levels that the pasteurization process must eliminate. Our pasteurization study is designed to better replicate real-world conditions to deliver the pasteurization treatment parameters set forth in the CFR and PMO, and to assess their effectiveness in inactivating HPAI H5N1 in bovine milk and other dairy products.

The results from this study will help further the FDA’s understanding of pasteurization efficacy against anticipated concentrations of virus under real-world processing conditions. The pasteurization study is ongoing and we anticipate making preliminary results available in the near future.

Today, the agency is also announcing an additional $8 million is being made available to support its ongoing response activities to ensure the safety of the commercial milk supply. This funding will support the agency’s ability to validate pasteurization criteria, conduct surveillance at different points in the milk production system, bolster laboratory capacity and provide needed resources to train staff on biosecurity procedures.

Additionally, these funds will help support HPAI H5N1 activities in partnership with state co-regulatory partners, who administer state programs as part of the federal/state milk safety system. It may also allow the FDA to partner with universities on critical research questions.

To date, the totality of evidence – including studies on the effectiveness of pasteurization against multiple pathogens, recent studies on the effectiveness of pasteurization of HPAI H5N1 in eggs at lower temperatures than generally used in dairy products, negative retail sample results to date, and real-world evidence from the last 100 years of the PMO — continues to indicate that the commercial milk supply is safe.

At the same time, the FDA also continues to advise against the consumption of raw milk (milk that has not been pasteurized). The FDA and CDC have long standing information regarding the increased risk of foodborne illness associated with numerous pathogens that may be present in raw milk. This increased risk exists for both humans and other animals that might drink raw milk. Additional guidance on raw milk and milk handling can be found on our website.

We are committed to continuing to initiate, support, and collaborate on research and surveillance of milk production, processing, and pasteurization to further our public health goals.