Scientists are sounding alarms about a genetic mutation that was recently identified in four dairy cow herds, nearly one year after H5N1 bird flu was first reported in Texas dairy cattle.

The ongoing bird flu outbreak has led to wild bird deaths, slaughtered livestock, and hazardous conditions for dairy industry workers.

Highly pathogenic avian influenza (HPAI) readily infected cells from milk-producing organs in dairy cows, but beef cells held it off, and virus behaviour was different depending on if it spread through a bird or another mammal.

Avian flu is not just for the birds; cases have been reported in the United States in dairy cows, as well as types of cats, a fox, a seal, and most recently, rats and domestic indoor cats, according to the latest data from the US Department of Agriculture (USDA)’s Animal and Plant Health Inspection Service (APHIS).

San Jose, Calif. — Bird flu isn’t just affecting chickens and cows; it’s hitting pet cats.

Avian flu is hitting California’s San Joaquin Valley hard — nearly 20 million chickens, ducks and turkeys have been killed in the region since 2022, according to data from the Centers for Disease Control and Prevention.

While the ongoing H5N1 outbreak has affected the United States, it is good to know what the avian flu is and how the virus can hit cats.