Pasteurizing Milk Inactivates Highly Infectious Bird Flu: USDA Report

H5N1 was discovered in dairy cows in March—marking the first time dairy cattle have become infected. It has since been found in 200 animals and three people.

Cows graze in a field at a dairy farm in Petaluma, Calif., on April 26, 2024. Justin Sullivan/Getty Images

Pasteurizing milk kills highly pathogenic bird flu virus H5N1, though some viral RNA may remain, a study conducted by researchers at the U.S. Department of Agriculture (USDA) finds.

The study, published Wednesday in the Journal of Virology, evaluated nearly 300 pasteurized milk samples. About 20 percent contained noninfectious virus RNA, and the authors determined that the milk did not pose a risk to public health.