More US cows being tested, tracked in bid to stop bird flu

FILE - Cows are pictured at a dairy in California, Nov. 23, 2016. The U.S. Food and Drug Administration said April 23, 2024, that samples of pasteurized milk had tested positive for remnants of the bird flu virus that has infected dairy cows.

U.S. health and agriculture officials are ramping up testing and tracking of bird flu in dairy cows in an urgent effort to understand — and stop — the growing outbreak.