Minimal Health Risks from Inactive H5N1 Virus in Pasteurized Milk Confirmed by Recent Research

Recent scientific findings from St. Jude Children's Research Hospital reveal that pasteurized milk contaminated with inactive H5N1 influenza virus poses little to no health risk to consumers. Although proteins and genetic fragments of the virus can be detected in pasteurized dairy products, the inactivation process effectively neutralizes their infectious potential.

The study specifically examined whether consuming pasteurized milk containing viral components could influence immune responses or increase susceptibility to influenza infections. Researchers found that such exposure did not significantly affect the immune system's ability to handle subsequent flu viruses, indicating minimal health concern.

Despite the safety of pasteurized milk, the research highlights the dangers of unpasteurized milk, which, if contaminated with live H5N1 virus, can cause severe disease and death, as demonstrated in mouse models. Proper pasteurization is emphasized as crucial in eliminating infectious viral particles from milk. The study also considered the impact of pre-existing immunity, finding that prior infection or vaccination against influenza provides robust protection, regardless of viral exposure through contaminated milk.

The findings support current food safety practices and vaccination strategies, reinforcing that pasteurized milk is safe for consumption even during outbreaks of H5N1 in dairy cattle. However, ongoing vigilance and strict adherence to pasteurization standards remain essential to prevent the risk of zoonotic transmission.

For further details, see the full study published in Science Advances: [DOI: 10.1126/sciadv.aeb3906]. Source: https://medicalxpress.com/news/2025-09-inactive-h5n1-influenza-virus-pasteurized.html