In May 2026, the CDC published the first documented evidence of a domestic cat transmitting H5N1 bird flu to a human. The key risk factor in every confirmed cat case so far has been raw poultry-based pet food, raw meat, or raw milk. If your cat eats only commercially cooked or canned food, the risk is very low. If your cat eats any raw poultry-based product, stop feeding it now. If your cat shows fever, loss of appetite, trouble breathing, or neurological signs such as wobbling or seizures after eating raw food, contact your vet immediately and mention the food type.
Most cat owners heard a version of this headline in May 2026 and wondered how worried to be. The short answer is: it depends almost entirely on what you feed your cat. Here is a clear breakdown of the actual science, not the panic.
What the CDC Actually Found
In late 2024 and early 2025, 19 domestic cats across five Los Angeles County households became severely ill after eating raw animal products, including commercially purchased raw poultry and raw milk. Nine tested positive for H5N1 clade 2.3.4.4b, the same strain driving outbreaks in dairy cattle and poultry across the US. Fourteen of the cats died or were euthanized.
Investigators from the Los Angeles County Department of Public Health and CDC then followed up with 139 people who had been exposed to those cats, including pet owners, veterinary staff, and animal control workers. Of the 25 who agreed to blood testing months after the exposure, one person showed serologic evidence of prior H5N1 infection. That finding, published in the CDC's Morbidity and Mortality Weekly Report on May 7, 2026, represents the first documented evidence of possible cat-to-human H5N1 transmission.
The person who tested positive was an asymptomatic veterinary professional. They had handled multiple infected cats during clinical procedures without wearing respiratory or eye protection. They reported no other known risk factors for H5N1 exposure. A follow-up PCR test taken seven days after exposure had come back negative, but the blood antibody test taken 120 days later told a different story.
How Cats Are Getting H5N1
In every documented case among domestic cats in the United States, the source has been consistent: raw animal products. Cornell University's Feline Health Center has tracked multiple clusters linked to commercially purchased raw cat food brands, raw poultry meat, and unpasteurized milk. The H5N1 virus contaminates poultry during slaughter or processing when infected birds enter the supply chain, and raw food processing does not destroy the virus the way heat treatment does.
What makes this particularly relevant for cat owners is that several major raw pet food brands have issued voluntary recalls specifically because of confirmed H5N1 contamination. This is not a theoretical risk buried in epidemiology reports. It has resulted in actual cats dying in actual homes across California, Oregon, and other states. Research published in Emerging Infectious Diseases documented H5N1 in cat urine weeks after a cat survived infection from contaminated raw milk, raising questions about shedding duration and environmental contamination in homes.
Indoor-only status provides no protection if the food source is contaminated. Every cat in the Los Angeles cluster that tested positive was described by owners as an indoor-only pet.
Which raw products carry the highest risk?
Poultry-based raw diets carry the most consistent risk because avian influenza is, by definition, a virus that circulates primarily in birds. Raw chicken, turkey, duck, and quail-based pet foods have all been implicated in confirmed cases. Raw milk is also high risk, as the virus has been detected in milk from infected dairy cattle. The Worms and Germs infectious disease blog, maintained by Dr. Scott Weese of the University of Guelph, notes that freeze-dried raw products should be considered similarly high risk since the freeze-drying process does not kill influenza viruses. High-pressure pasteurized raw food carries lower but not zero risk.
Non-poultry raw products such as beef or pork carry meaningfully lower risk because H5N1 circulates primarily in birds, not in those species. That said, cross-contamination during manufacturing is possible.
Symptoms of H5N1 in Cats
H5N1 infection in cats is not subtle when it takes hold. The pattern seen across documented cases is consistent. Initial signs typically include fever, sudden loss of appetite, and lethargy. These progress quickly. Unlike most common cat illnesses where owners have days to observe changes, H5N1 can move from initial symptoms to severe neurological disease within 48 to 72 hours in some cats.
The full list of documented signs, as described by Cornell's Feline Health Center, includes:
- Fever and general malaise
- Loss of appetite (often sudden and complete)
- Lethargy
- Respiratory difficulty, including labored breathing or open-mouth breathing
- Incoordination and stumbling
- Tremors
- Seizures
- In late stages: blindness, circling, and copious eye and nose discharge
Neurological signs are a particularly consistent feature. Research published in Emerging Infectious Diseases describing cases in dairy farm cats documented depressed mental state, stiff body movements, ataxia, and blindness as prominent clinical features. The disease can look very different from ordinary cat flu and can be mistaken for other neurological conditions if the raw food history is not disclosed to the vet.
The Real Risk to Cat Owners
The May 2026 MMWR finding is significant precisely because cat-to-human transmission had not been documented before. But it is important to read what actually happened carefully. Of 139 people with exposure, 25 agreed to blood testing, and one person had antibody evidence of infection. That person was asymptomatic throughout, worked as a veterinary professional with prolonged close contact involving airway procedures on infected cats, and wore no respiratory or eye protection during those procedures.
The American Veterinary Medical Association notes that CDC authors emphasized the overall risk to the general public remains low and there is no evidence of sustained human-to-human transmission. For the typical cat owner whose cat eats cooked food and has not been exposed to any raw poultry products, the risk is negligible based on all available evidence.
The meaningful risk exists for people who have direct, prolonged, unprotected contact with a cat that may have eaten contaminated raw food and is showing signs of illness. Veterinary professionals handling sick cats need to wear respiratory and eye protection as a standard precaution, as the CDC report makes clear. For home cat owners, the practical protection is primarily dietary, not contact-related.
What Cat Owners Should Do Now
The guidance from the CDC, the AVMA, and Cornell's Feline Health Center is consistent and straightforward.
Stop feeding raw poultry-based food immediately. This means raw cat food made with chicken, turkey, duck, or other poultry. It also means raw milk and raw meat. These products carry the most significant H5N1 risk based on all documented cases to date. If you have unused product at home, bag it and dispose of it.
Check current recall lists. Multiple raw pet food brands have issued H5N1-related recalls. The FDA maintains a current list at FDA.gov. Do not assume a product is safe because you have been buying it for months without incident. Contamination can occur in specific production batches, not across an entire brand's history.
Clean surfaces where raw food was prepared. H5N1 is relatively fragile in the environment compared to some viruses, but any surfaces, bowls, or utensils that contacted raw poultry products should be washed with soap and hot water. Diluted bleach solution provides additional assurance on hard surfaces.
If you choose to continue raw feeding despite the risks, limit it to red meat sources such as beef or lamb, avoid all poultry-based products, and look specifically for high-pressure pasteurized products, which carry substantially lower risk. Understand this is still a risk-reduction approach, not a risk-elimination one.
For cat owners who are uncertain about transitioning away from raw food, our guide on getting a cat to accept new food covers the transition approach that minimizes digestive upset and refusal behavior.
When to Call Your Vet
If your cat has eaten any raw poultry-based product in the past two to three weeks and develops any of the following signs, contact your veterinarian the same day and tell them specifically about the raw food history:
- Fever (you can check with a rectal thermometer: above 103.5F is concerning)
- Complete loss of appetite lasting more than 24 hours
- Any difficulty breathing or respiratory distress
- Stumbling, wobbling, or loss of coordination
- Tremors or seizure-like activity
- Sudden change in eye appearance or apparent blindness
Disclosing the raw food history to your vet is critical. Vets are currently being advised by the AVMA to consider H5N1 in cats presenting with acute respiratory or neurological illness, but they can only do that if you mention what your cat has been eating. PCR testing on nasal swabs can confirm H5N1, and urine testing is also an option in some cases based on Cornell's published research.
Veterinary staff treating a potentially H5N1-positive cat will follow infection control protocols including personal protective equipment. You do not need to handle any secretions from a sick cat without gloves, and avoid touching your face after handling an ill cat before washing hands thoroughly.
For broader guidance on emergency cat situations, our guide to emergency vet signs in cats covers triage across all major urgent conditions.