flu-virus-stays-infectious-in-raw-milk-for-5-days-study

The influenza virus has been found to stay infectious in refrigerated raw milk for as long as five days, according to researchers. 

 

This recent study from Stanford University comes amidst concerns about possible new pandemics linked to bird flu outbreaks in cattle. 

 

Alexandria Boehm, the study’s senior author from the Stanford Doerr School of Sustainability and the Stanford School of Engineering, emphasised the potential danger of avian influenza spreading through raw milk consumption and highlighted the need for milk pasteurisation. 

 

Supporters of raw milk argue that it retains more beneficial nutrients, enzymes, and probiotics compared to pasteurised milk, which they claim can enhance immune and gut health. 

 

The US Food and Drug Administration (FDA) has associated raw milk with over 200 reported illness outbreaks and cautions that pathogens such as E. coli and Salmonella in raw milk pose "serious" health threats, especially to vulnerable groups like children, the elderly, pregnant women, and those with weakened immune systems. 

 

The research, published in Environmental Science and Technology Letters, investigated how a strain of the human influenza virus persists in raw cow’s milk under usual refrigeration conditions. 

 

The H1N1 PR8 strain of the flu virus was shown to survive and retain its infectious nature in the milk for up to five days. 

 

Mengyang Zhang, a postdoctoral scholar in civil and environmental engineering and co-lead author of the study, noted that the duration for which infectious influenza virus persists in raw milk raises alarm about possible transmission pathways. “The virus might contaminate surfaces and various environmental materials in dairy facilities, posing risks to both animals and humans.” 

 

Additionally, the researchers discovered that flu virus RNA—genetic material that is not deemed a health risk—remained detectable in raw milk for at least 57 days. 

 

In contrast, pasteurisation effectively eradicated infectious influenza from the milk and decreased the presence of viral RNA by nearly 90%, although some RNA remained. 

 

The results stress the necessity of enhancing monitoring systems, particularly in light of the ongoing spread of bird flu among livestock, according to the authors of the study.