Several cats have fallen ill and died after contracting the H5N1 bird flu from raw food or unpasteurized milk.

According to NPR, infectious disease expert Dr. Jane Sykes, of the University of California, Davis School of Veterinary Medicine warns that consuming raw milk or meat, even if it’s in the form of pet food, can be hazardous. The Food and Drug Administration (FDA) recently issued a requirement that manufacturers of cat and dog food review their food safety plans to include the proper processing of their products to prevent the hazards of H5N1.

“We encourage consumers to carefully consider the risk of this emerging pathogen before feeding their pets uncooked meat or an uncooked pet food product,” the agency said, added CNN.

In the meantime, veterinarians recommend sticking to conventional pet food that’s been heated, canned and pasteurized to neutralize the virus. Pet owners should try and supervise their cats on the prowl to discourage them from catching and eating birds outdoors.

The symptoms of bird flu in cats are lethargy, runny nose, or discharge around the yes. While upper respiratory illnesses in cats are common, the bird flu is still rare, says Sykes. Bird flu can also cause neurological symptoms such as dizziness and seizures, but rabies can also cause these signs. Make sure your cats are up to date with their vaccinations.

The American Veterinary Association says that so far, there has been no cat-to-human transmission of bird flu, although it doesn’t rule out that possibility. Sykes says that since viruses mutate over time, there is a chance that this particular strain can adapt to spreading to humans.

The FDA says that dogs are also vulnerable to bird flu infections, which tend to be milder in dogs than in cats. Other mammals such as large cats, foxes and opossums can also become infected. However, domestic cats are the third most common detection of H5N in non-farm animals in the U.S., behind foxes and mice, notes CNN.

 In the meantime, experts discourage pet owners from feeding raw food and unpasteurized milk to their domestic animals. While feeding raw food to pets is a growing and popular trend, veterinary experts say there is no nutritional advantage to this practice, and the risks of raw food far outweigh the potential benefits.