What to Know About Bird Flu After Third US Infection: QuickTake

A strain of highly pathogenic avian influenza that’s been decimating wild and captive flocks of birds since 2020 is spreading among US dairy cows — and has now infected three farmworkers exposed to sick cattle. The Centers for Disease Control and Prevention says the overall risk to the general public remains low, but public-health officials remain on alert for any indication of the most feared outcome: human-to-human transmission that could trigger a pandemic.

When did this flu begin spreading?

This strain of bird flu, H5N1, was first discovered in 1996 in geese bred in southern China. It’s proved to be ...