If you need another reason to keep your feline pets indoors, read on. Since March 2024, when a bird flu virus (H5N1) outbreak occurred in dairy cattle in the United States, dozens of domestic cats (including barn and feral cats) and “big” cats located in zoos and in the wild (e.g., mountain lions, tigers, leopards, and bobcats) have died from the virus. According to the American Veterinary Medical Association (AVMA) (https://www.avma.org/resources-tools/animal-health-and-welfare/animal-health/avian-influenza/avian-influenza-h5n1-cats ), cats appear to be highly susceptible to the virus. More importantly, once clinical symptoms occur, the disease’s outcome is typically fatal within the week.
Avian influenza is so contagious in poultry that an entire flock is culled as soon as the presence of the virus is confirmed. Since federal and state government officials began tracking in February 2022, at least 1,400 outbreaks have been reported in more than 600 counties nationwide, affecting nearly 135 million birds. Positive bird flu detections in domestic cats were gathered in January 2025 in California, Kansas, Louisiana and Iowa. What is known is that in December 2024, the Santa Barbara County Public Health Department confirmed two cases of the flu in domestic cats after being fed raw milk, eggs, and chicken. That same month, Northwest Naturals pet food company issued a recall of one type of its raw frozen pet food when a house cat in Oregon died after eating the food, which later tested positive for H5N1.
The first human case in the US occurred in April 2024. Since then the CDC (Centers for Disease Control and Prevention (https://www.cdc.gov/bird-flu/situation-summary/index.html )) reported a total of 70 confirmed human cases, with the first death occurring this past January in Louisiana. Most human cases are quite mild, and the current public health risk remains low according to the CDC. Most human infection is due to exposure from commercial agriculture operations, like dairy cattle herds and poultry farms. However, it is also possible for infected cats to transmit the virus to people, though the risk of cat-to-human transmission is considered low. However, be aware that with prolonged, unprotected exposure to infected animals the risk increases.
Bird flu is present in wild birds (turkey vultures, mallards, etc.)( https://www.cdc.gov/bird-flu/situation-summary/data-map-wild-birds.html ), poultry (ducks, chickens, turkeys, etc.)( https://www.cdc.gov/bird-flu/situation-summary/data-map-commercial.html ) and dairy cattle (https://www.aphis.usda.gov/livestock-poultry-disease/avian/avian-influenza/hpai-detections/hpai-confirmed-cases-livestock ). Bird flu was also documented in raccoons, black rats, fishers, and feral and domestic cats in California (https://www.aphis.usda.gov/livestock-poultry-disease/avian/avian-influenza/hpai-detections ).
The AVMA and the European Advisory Board on Cat Diseases (ABCD)( https://www.abcdcatsvets.org/ ) offered the following suggestions for the prevention of transmittal of the virus: do not feed cats raw dairy products (since pasteurization kills the virus, pasteurized milk is safe for human consumption); do not feed raw meat diets or treats, being sure to thoroughly cook any meat before feeding it to cats; keep cats indoors to prevent exposure to birds, other wildlife and livestock, and poultry in areas with known H5N1 outbreaks; always follow good hand washing techniques, and be sure to change clothes and shoes after interacting with animals believed to have the virus; immediately contact your veterinarian if you think your cat might have been exposed to the virus. If H5N1-virus infection in a cat is suspected, minimize all direct physical contact with the cat, avoiding any potential scratching and biting; wear gloves, a mask, and protective eyewear when handling the feline; the cat should also be confined to a separate room; litter trays, bowls, bedding and other contaminated objects should be disinfected using household bleach. Limit the cat’s contact with children younger than 5, people with weakened immune systems, people over 65 years and pregnant women.
According to the AVMA and the ABCD, clinical signs of cats infected with the H5N1 avian virus (https://pmc.ncbi.nlm.nih.gov/articles/PMC10822538/ ) are: fever, lethargy, severe depression (little to no interest in doing anything), conjunctivitis, jaundice, and loss of appetite. It also noted that bird flu in domestic cats can quickly progress with neurological signs like tremors, seizures, ataxia (lack of muscle coordination and control) or loss of coordination and balance, circling, or blindness. Several cases have also reported large amounts of discharge from the eyes and nose, and other respiratory signs like tachypnea (abnormally rapid breathing), dyspnea (shortness of breath), and possibly sneezing or coughing.
Early signs of bird flu in cats can appear similar to many other illnesses such as: Feline herpesvirus (FVR and FHV-1); calicivirus (a highly contagious virus that causes a mild to severe respiratory infection and oral disease in cats); Bordetella bronchiseptica (a pathogenic bacteria of domestic cats, particularly in high population density conditions); Chlamydophila Felis (a bacterium that can infect cats of any age, the most common symptom is conjunctivitis); and mycoplasma (caused by a type of bacteria that acts as a parasite in the blood, causing anemia and other signs of infection). However, with cats who contract the H5N1 avian virus the progression to death can be rapid, with some succumbing within 24 hours of showing symptoms.
Additional information: USDA (Us Department of Agriculture) https://www.aphis.usda.gov/livestock-poultry-disease/avian/avian-influenza; The Center for Food Security and Public Health (https://www.cfsph.iastate.edu/diseaseinfo/disease/?disease=avian-influenza&lang=en ); and the World Organisation for Animal Health ( https://www.woah.org/en/disease/avian-influenza/ ).
