Bird flu cases are still rising in the U.S. as the virus continues to devastate poultry farms. More than 145 million chickens, ducks, turkeys and other fowl have been slaughtered across the United States since the outbreak began in January 2022. As for humans, 67 people have been infected, according to the Centers for Disease Control.

While the H5N1 bird flu keep spreading, the first reported H5N9 outbreak in the United States has been identified on a duck farm in California.

H5N9 is a rare subtype of the influenza A virus that can cause highly pathogenic avian influenza (HPAI), also known as bird flu. It's a reassortment strain that originated from the H5N1, H7N9, and H9N2 subtypes.