Colorado has the most cases of bird flu among dairy cows in the U.S.

Cases of highly pathogenic avian flu cases in Colorado dairy cows keep rising, with numbers from a federal website recording the state as having more cases than any other. Public health experts said they’re watching to see if infections spillover from cattle to  humans and then human to human. “I think it's an important time for public health to be watching this really closely,” said  Elizabeth Carlton, an epidemiologist at the Colorado School of Public Health. “Concern for the general public is pretty low right now,” she said.