About 1 in 15 pet cats carry a gut parasite, study finds
About one in 15 pet cats tested carried Giardia, a gut parasite nicknamed "beaver fever," a large study in the journal PLOS One found. About one in five infected cats had strains that can also sicken people. The study looked at more than 150,000 stool samples from cats across the U.S. and Canada.
Your cat could be carrying a parasite that can also make people sick, a new study suggests.
Researchers tested more than 150,000 cat stool samples sent to labs between March 2022 and August 2023. The samples came from cats in 49 states, Washington, D.C., and five Canadian provinces. About 6.3%, or roughly one in 15, tested positive for Giardia duodenalis, Gizmodo reported. Of those, about one in five carried types that can infect humans. The study was published Wednesday in the journal PLOS One.
Giardia lives in the gut and spreads through stool. It can cause diarrhea, cramps and bloating in people and pets. Some infected animals show no signs at all. The nickname "beaver fever" caught on in the 1970s after outbreaks were tied to water where beavers lived, ABC News reported. Giardia is the most common parasitic disease in the U.S., with more than a million cases a year, according to the Centers for Disease Control and Prevention.
Kittens were more likely to test positive than older cats, and male cats more than females. Cases were less common in summer, likely because the parasite survives better in cool, damp conditions. Cats in the Midwest had higher rates.
The researchers work for Mars Veterinary Health and Antech Diagnostics, both part of Mars Petcare, which runs large vet clinic and lab networks. "Some infected cats may not appear sick," co-author Dr. Anne Kimmerlein told Gizmodo. She said owners should not assume their cat is safe just because it stays indoors.
People usually catch Giardia from dirty water or close contact with stool. Cats are only one possible source. The infection is usually very treatable.
Emergency veterinarian Dr. Stevie Aitken told ABC News that owners of an infected cat should clean litter boxes and food and water bowls well. "Wash your hands, don't let animals lick your face or your mouth, and keep kids away from litter boxes," Aitken said. Vets generally advise a yearly stool test, and more often for young or outdoor cats.
What we know: Giardia is common in pet cats, and some strains can spread to people.
What we don't: How often cats actually pass the parasite to their owners.
Where outlets agree ABC News and Gizmodo both report that the study tested more than 150,000 cat stool samples and found Giardia in about one in 15 cats.
Where they differ Gizmodo reports the infection risk was highest in young, male and unneutered cats, while ABC News reports that neutered kittens had a markedly higher likelihood of infection.
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