Pasteurization completely inactivates bird flu from raw milk, FDA says

Over 100 dairy cattle herds in around a dozen states have reported cases of the highly infectious disease since March.
Posted at 2:03 PM, Jul 01, 2024

The U.S. Department of Agriculture has announced the results of a study showing pasteurization is effective at inactivating the virus popularly known as the "bird flu" in milk and other dairy products.

The FDA said the study is the first to simulate commercial milk processing. It found that "the most commonly used pasteurization time and temperature requirements were effective at inactivating the H5N1 HPAI virus in milk."

Researchers tested 275 raw milk samples obtained from farms in four states where bird flu has been known to spread. Out of those samples, 158 tested positive for "viral fragments" of bird flu, while 39 were found to have infectious virus.

They then took these milk samples and heated them to 161 degrees Fahrenheit for 15 seconds. The FDA said warming the milk was "effective at eliminating the levels of virus found in raw milk."

Next, they spiked milk with higher levels of virus to see if pasteurization remained effective. The FDA said that pasteurization treatment "completely inactivated" the virus.

“While testing finished product post-pasteurization is one strategy to detect potential problems in finished products, validating the effectiveness of the pasteurization parameters critically demonstrates that commercial milk processing is capable of controlling the HPAI virus and further provides broad assurance that pasteurized milk and dairy products made from pasteurized milk are safe,” said Nathan Anderson, a director in the FDA’s Center for Food Safety and Applied Nutrition.

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The Centers for Disease Control and Prevention says over 100 dairy cattle herds in around a dozen states have reported cases of the highly infectious disease since March.

Bird flu typically spreads from animal to animal, but has jumped to four humans in the U.S. since 2022, all of whom interacted with infected cows or poultry.

The FDA said it continues to recommend against the consumption of unpasteurized raw milk, although the FDA said that it's still unknown whether someone can become infected with bird flu by consuming raw milk.

"Pasteurization is a proven process with a 100-year history of protecting public health and is highly effective at eliminating the dangers associated with consuming raw milk," the FDA said.

The National Institutes of Health said that as of 2022, at least 4.4% of the U.S. population reported consuming raw milk. At the time, an estimated 2.5 million adults consumed raw milk on at least a weekly basis.