What we know about the deadliest U.S. bird flu outbreak in 7 years

The price of eggs has risen sharply since the start of a bird flu outbreak that has resulted in millions of birds being culled.

Justin Sullivan / Justin Sullivan

A highly pathogenic bird flu virus is tearing its way through U.S. farms and chicken yards, spreading to at least 24 states less than two months after the first outbreak was reported in a commercial flock.

Nearly 23 million birds have died. It’s the worst U.S. outbreak of the avian flu since 2015, when more than 50 million birds died. The outbreak is driving up consumer prices for eggs and chicken meat that, like many costs, had already been rising due to inflation.

Here’s what you need to know about the outbreak.