Since 2022, a growing number of mammals—including more than 80 domestic cats—have been confirmed to carry H5N1, the highly pathogenic strain of bird flu currently circulating in the United States. While many of these infected cats were barn cats or outdoor pets that likely hunted diseased rodents or wild birds, house cats have also begun testing positive after consuming raw meat or unpasteurized milk. In some cases, these infected cats died
Why House Cats Pose a Risk
Although this strain of H5N1 hasn’t evolved to spread efficiently among humans, the concern is that cats—often described as “semi-domesticated” because of their instinct to roam and hunt—could bring bird flu into the home. As virologist Angela Rasmussen from the University of Saskatchewan emphasizes, cats can be a “100% public health risk” when it comes to zoonotic transmission because we live in close contact with them. Sharing beds, cuddling, and letting them roam freely on kitchen counters could create a route for infection if a cat carries a contagious virus.
How Is H5N1 Transmitted?
Direct contact with infected birds or animals: Cats that spend time outdoors may hunt or scavenge diseased birds or rodents.
Consumption of contaminated products: Raw meat or unpasteurized dairy from infected sources has been linked to feline H5N1 infection.
Close contact at home: Theoretically, if a cat becomes infected, it could shed the virus and potentially expose other animals or people.
Symptoms of Bird Flu in Cats
According to Michael Q. Bailey of the American Veterinary Medical Association, signs of H5N1 in cats can include:
Respiratory symptoms: Runny nose or discharge around the eyes.
Neurological symptoms: Dizziness, disorientation, and seizures—similar to signs of rabies.
If you notice these symptoms, it’s essential to consult a veterinarian immediately. While bird flu remains relatively rare, early detection can prevent complications.
Why You Shouldn’t Panic—But Stay Vigilant
Experts, including Rasmussen, stress that while the risk of a cat transmitting H5N1 to humans is currently low, it’s not zero. Bruce Kornreich, director of Cornell University’s Feline Health Center, notes that cats’ wide range of possible hosts and roaming behaviors make them potential carriers. Still, the predominant human cases of H5N1 have involved direct contact with infected poultry on farms, not household pets.
Take Precautions
Keep vaccinations up-to-date: This includes routine vaccinations and keeping an eye on emerging or recommended vaccines.
Restrict outdoor access: Whenever possible, discourage unsupervised roaming to reduce exposure to infected wildlife or stray animals.
Practice good hygiene: Wash your hands after handling pets, and avoid letting cats drink from your glass or sit on areas where you prepare food.
The Raw Food Debate
Increased Risk from Raw Diets
Some cat owners opt for raw meat or unpasteurized milk, believing it to be more natural or nutritious. However, the American Veterinary Medical Association warns against feeding raw diets because they can contain pathogens like salmonella, listeria—and now H5N1. Cases have emerged in which indoor-only cats became infected after eating contaminated products.
Recent Recalls
Northwest Naturals voluntarily recalled a batch of its frozen turkey-based pet food after one indoor cat that consumed the product died. Testing showed a genetic match between the virus in the food and the cat.
Raw Farm recalled its unpasteurized milk and cream after multiple cats tested positive for H5N1. The cats had reportedly consumed Raw Farm’s products.
What About Cooked or Commercial Pet Food?
Veterinarian Jane Sykes from the University of California-Davis reassures pet owners that conventional dry or canned pet food is generally safe because the heating process kills viruses, including H5N1.
More Cases, More Chances for Mutation
The growing presence of H5N1 in different animal species fuels concern about viral mutation or reassortment—when a host (like a cat, pig, or human) is infected by two different influenza viruses at once and they exchange genetic material. Although such events are rare, they can produce new strains that could spread more easily among humans.
1918 Flu Pandemic: Likely originated from an avian virus and remains a stark example of how dangerous reassortment events can be.
Seasonal Flu Overlap: If someone already has seasonal flu and then becomes exposed to H5N1, there’s a small possibility the viruses could mix.
The Role of Public Health Surveillance
Most human H5N1 cases in the U.S. have occurred in agricultural workers. Still, researchers and public health agencies call for expanded surveillance in companion animals. Monitoring early signs and possible transmission can help prevent larger outbreaks, especially if the virus mutates into a more contagious form.
Delayed Research
A forthcoming CDC study on H5N1 in cats—initially delayed—suggests that house cats likely contracted bird flu from dairy farm workers. As viruses continue to evolve, scientific efforts aim to better understand how feline infections begin and whether the virus can spread further through households or communities.
The Outlook for Dogs
Dogs can contract certain strains of bird flu, but confirmed H5N1 cases in U.S. dogs are currently nonexistent. While dogs in some countries have tested positive and, in rare cases, died from bird flu, they appear less susceptible than cats. Behavioral factors—such as fewer free-roaming dog packs compared to feral cat colonies—may contribute to their lower risk.
How to Protect Your Home
Although H5N1 is “flying around” in migratory birds, you can reduce your household risk by:
Avoiding Raw Pet Food: Stick to commercially prepared dry or canned products.
Refraining from Unpasteurized Dairy: Don’t let cats drink raw milk or cream.
Supervising Outdoor Activity: Keep cats indoors or under close watch to minimize hunting or scavenging.
Practicing Good Pet Hygiene: Regularly clean litter boxes, bedding, and feeding bowls.
Staying Informed: Follow updates from public health agencies and veterinary organizations.
While experts say there’s no need to panic about a looming cat-driven bird flu pandemic, awareness and precaution are key. By limiting pets’ exposure to potential carriers, feeding them properly prepared food, and maintaining good hygiene practices, you can keep your pets safe and reduce the overall risk of H5N1 transmission.
As bird flu continues to circulate among wildlife, ongoing research and vigilant surveillance will be critical to ensuring that house cats—and their human companions—stay healthy.