More than half of New York City’s free-roaming cats carry at least one zoonotic parasite.
Of 87 cats tested in a new study published in PLOS One, 50 tested positive for at least one endoparasite—a parasite that lives inside a host’s gut, lungs, heart or blood vessels. The most common infection was Toxocara, a type of parasitic roundworm that colonizes the intestines.
In the study, led by Pratap Kafle, an assistant professor of parasitology at Rowan University’s Shreiber School of Veterinary Medicine in Glassboro, New Jersey, the research team collected fecal and blood samples from cats during a Trap-Neuter-Return program in 2023.
The researchers also found that sex and life stage affected how many parasite eggs the cats shed into the environment and whether or not they’re infected in the first place. Male cats shed three times as many Toxocara eggs into the environment compared to females and are four times as likely to be infected. Young cats shed nearly nine times as many parasite eggs compared to adults.
Describing young males as “super-shedders,” researchers said that Trap-Neuter-Return programs may help lower the transmission risk of certain parasites to humans by targeting deworming treatment on young male cats. Young children are especially at risk of roundworm infection because of their use of city parks and playgrounds.
