Study Reveals Pasteurization Removes H5N1 Virus from Milk

In March 2024, Texas dairy cows were infected with H5N1 bird flu. It was the first known case of the virus in cattle. After that, H5N1 has been found in 200 animals and three people across 12 states. The virus was detected in raw milk. Hence researchers are trying to study if dairy products can infect people. 

A reputed virologist, Erica Spackman and her colleagues have recently conducted a study at the U.S. Department of Agriculture. They found no infectious virus in nearly 300 milk products from 132 processors. 

This study was recently published in the Journal of Virology. Researchers believe milk is safe due to the sanitation processes in place. The sanitation process removes some pathogens such as bacteria and other viruses that can occur in milk. 

The milk processing pipeline has multiple layers of protection. It includes microbiological surveillance that identifies pathogens, prevents milk from cows with mastitis from entering the food supply and heat during pasteurization that destroys common bacterial pathogens. 

Bird flu is an infection that mostly affects birds that migrate. It can also spread to other animals such as goats, cats, dogs, polar bears, elephants, and seals. But it was very surprising to find the virus in dairy cows because this infection was never seen in them before. After the discovery, tests showed that the virus was found in raw milk. This suggests that the virus can be passed from cows to raw milk.  

The FDA and USDA also studied whether pasteurization effectively removes risks in milk. They tested 297 samples of pasteurized milk from 17 states between April 18 and April 22, 2024. They used a method called real-time PCR. The samples included 23 different types of milk products. 

Researchers of this study did a test to find live virus. When they observed the results, they couldn’t find any virus in pasteurized milk. They used a very sensitive method but still couldn’t detect any virus. But they found viral genetic material in 20% of the samples using a different method called PCR. It seems like the virus is not active anymore. 

Researchers of this study said that these new findings make us feel better because pasteurization keeps us safe from unknown dangers. 

The result of this study clearly shows that pasteurized milk is safe because the process removes all the dangerous pathogens. Hence this study is very helpful as it shows positive effects of pasteurization.