- September 22, 2025
- By Fid Thompson
Bird flu hits cats particularly hard—a fact demonstrated again in recent weeks when an infected cat was euthanized in California after eating raw pet food. But a University of Maryland-led study published Thursday in the journal One Health shows promising results when an infected cat gets early care and treatment with an antiviral drug.
“Cats need not be euthanized in every case,” said Kristen K. Coleman, the study’s lead researcher and an assistant professor at UMD’s School of Public Health specializing in airborne infectious diseases. “They can regain full health and what appears to be strong protection from reinfection for at least several months after recovery.” Coleman is also an affiliate assistant professor in UMD’s Department of Veterinary Medicine.
Last fall, four domestic cats in a home near Tulare, the epicenter of California’s avian flu outbreaks in dairy cattle, contracted the highly pathogenic avian influenza H5N1 virus from an unknown source. The first cat died suddenly at a local vet clinic after having breathing problems, and the second died within a few days of receiving antibiotics and fluids at a different clinic. The two remaining cats fell ill within the same week but survived after receiving prompt treatment including oseltamivir, which is the same antiviral used to treat influenza in humans.
“Being able to recognize and begin treatment at the first signs of illness gave us the best chance for success,” said Dr. Jake Gomez, the veterinarian who treated the cats at Cross Street Small Animal Veterinary Hospital in Tulare.
Symptoms in cats can begin with loss of appetite and fever and quickly progress to neurological signs, such as tremors and difficulty walking, discharge from nose and eyes and other respiratory problems such as trouble breathing. If bird flu is suspected, Coleman advises pet owners to share a paper on outbreaks of highly pathogenic avian influenza a (H5N1) among house cats with the veterinarian and request that the sick cat be empirically treated with the antiviral oseltamivir.
Bird flu spreads quickly through animals and researchers are concerned about infected cats posing an unexpected risk to family members and veterinarians caring for them.
“This virus can move rapidly through pets in a home, catching families off guard. Bird flu, especially this current strain, is highly deadly to cats,” said Coleman. “If you suspect your cat has bird flu, the best course of action is to act swiftly by seeking veterinary care. And although spillover infections from cats to humans are seemingly rare, they can happen.”
Although this case series involved just four domestic cats in a single household and is too small to be definitive, results highlight both the importance of rapid recognition of disease and the potential role of antiviral therapy in protecting animal health along with potentially reducing spillover cases, added Gomez.