On Jan. 13, 2025, the Los Angeles County Department of Public Health (LACDPH) reported that five indoor-only cats in one household experienced acute onset of illness after consuming two brands of commercially available raw pet food.

Four of the cats had severe clinical signs and two of them died. One cat had mild clinical signs. One of the severely affected cats was tested and later confirmed to be infected with H5N1 (aka H5 bird flu). Both raw pet food diets were tested, and one of the two raw pet foods, Monarch Raw Pet Food, was confirmed to contain live, infective, H5N1 virus.

Influenza A is rarely detected in cats. These are the first cats in LA County to be confirmed positive for H5 bird flu after consuming raw pet food products. Five other cats from two different households in LA County have also been confirmed with H5 bird flu after drinking raw milk for human consumption that was part of a recall due to H5 bird flu contamination. All five of these cats died from H5 bird flu.