New research shows that people who become infected with the novel coronavirus, or SARS-CoV-2, and fall ill often pass the pathogen on to their pets. The animals sometimes also become sick from the infection, occasionally severely, according to the results of two separate studies presented at this year’s European Congress of Clinical Microbiology and Infectious Diseases. The papers have not yet been published in scientific journals.

A team led by veterinarian Dorothee Bienzle of the University of Guelph in Ontario investigated potential COVID infection in 198 cats and 54 dogs. All of the dogs and 48 of the cats came from a household in which at least one person had COVID, and the rest of the cats came from an animal shelter or neuter clinic. The team found that two out of three cats and two out of five dogs whose owners had COVID had antibodies against SARS-CoV-2, indicating they had been infected with the virus at some point, too. But in the shelter group, less than one in 10 cats had these antibodies. And in the neuter clinic, the figure was less than one in 38.