Madison, Wisconsin – A recent study published in the New England Journal of Medicine has shed light on the potential dangers of consuming unpasteurized milk contaminated with H5N1 avian flu viruses. Researchers at the University of Wisconsin-Madison found that mice fed milk from H5N1-infected cows experienced severe illness, raising concerns about the risks associated with raw milk consumption.

While the study cannot definitively prove that humans who drink raw milk containing the virus will fall ill, experts warn of the potential dangers. Ethical constraints prevent studies of this nature from being conducted on humans, but the evidence from animal studies is concerning.

Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota, emphasized the suspicion surrounding raw milk as a potential transmitter of the H5N1 virus. He expressed uncertainty about the risks for humans but advised against taking any chances with consuming raw milk.

The study’s findings were not limited to mice. Reports of farm cats dying after consuming contaminated milk from infected cows further underscore the risks associated with raw milk consumption. Thijs Kuiken, a pathologist at the Erasmus Medical Center in Rotterdam, highlighted the likelihood of humans contracting systemic disease from consuming raw milk from infected cows.

The Food and Drug Administration has long warned against consuming raw milk due to the presence of various dangerous pathogens, including E. coli, Salmonella, and Listeria. The agency reiterated this advice in light of the H5N1 outbreak in dairy cattle across nine states, with two confirmed human infections among farm workers.

The study, led by researchers at the University of Wisconsin-Madison and senior author Yoshihiro Kawaoka, explored various aspects of milk contamination and pasteurization. Despite different pasteurization approaches reducing the amount of active virus in the milk to varying degrees, researchers cautioned that their methods may not align with commercial milk processing practices.

Furthermore, storing raw milk containing the virus at refrigerator temperature for several weeks showed only a minor reduction in virus levels, suggesting its infectiousness could persist for an extended period. The presence of H5N1 virus in the mammary glands of mice indicates the susceptibility of dairy cattle to the virus, with lactating cows shedding high levels of virus in their milk.

Overall, the study’s findings raise concerns about the potential risks associated with consuming raw milk contaminated with H5N1 avian flu viruses, emphasizing the importance of pasteurization processes in ensuring food safety.