Cat and dog owners who hug their pets while infected with COVID-19 could end up infecting their animals with the virus, according to a Canadian study.
While animals including cats, dogs, ferrets and hamsters are known to appear susceptible to COVID-19, transmission may occur more frequently than previously thought, the study said.
The study, published this month in the journal Emerging Infectious Diseases, involved 69 cats and 49 dogs, including pets and animals from shelters and neutering clinics.
Pet owners were also asked to fill out an online survey about the nature of their interactions with animals.
“These data suggest that human-to-animal transmission of SARS-CoV-2 is relatively common and that certain human-animal contact—eg, kissing pets, pets sleeping in beds—appears to increase risk,” the study said.
“We infer that, given the prevalence of this virus in humans and the limited exposure of most household pets to other animals, infection in dogs and cats reflects direct transmission from humans to animals.”
Study co-author Professor Scott Weiss, of the Ontario School of Veterinary Medicine at the University of Guelph, said dogs and cats living in shelters had lower rates of COVID-19 infection compared to people living with humans.
“As we expected, that’s a pretty big difference,” Weiss said.
Lead author Professor Dorothee Bienzle, from the University of Guelph’s Department of Pathobiology, said the results suggest that cats have a higher rate of COVID-19 infection than dogs.
“It has to do with how well the virus locks onto receptors in the cat’s or dog’s respiratory system,” Bienzle said.
The high prevalence of COVID-19 antibodies in cats surprised the researchers, she said.
“We didn’t expect so many,” she said. “More than half of the cats that live in the homes of COVID patients have antibodies. That’s a very high number.”
Animals infected with COVID-19 show symptoms similar to humans infected with the virus, she said.
“They don’t have any appetite, they feel bad, they sleep more, they may sneeze and cough,” she said.
Cats are able to transmit infections to each other and to humans, Weiss said.
He said a veterinarian in Thailand was diagnosed with COVID-19 in August 2021 when the veterinarian sneezed on an infected cat owned by a patient who had tested positive for the virus. Genetic analysis showed that the virus was passed from cat owners to pets and veterinarians, Weiss said.
There is also evidence that minks infected by humans can transmit the virus to others, he said.
Transmission from humans to animals can be minimized by maintaining distance, wearing masks and taking other precautions, just as they prevent infecting people, he said.
“Ideally, what we’re trying to do is stop it from spreading as much as possible so people can limit their contact with animals if they’re infected,” he said. “That’s ideal.”
The Canadian Press report was first published on June 26, 2022.