COVID-19 is common in pet cats and dogs whose owners are infected with the SARS-CoV-2 virus, according to a study. In the yet-to-be published study, researchers at Utrecht University in the Netherlands studied pet dogs and cats of people who had tested positive for COVID-19. A mobile veterinary clinic visited the homes of owners to take oropharyngeal and rectal swabs, and blood samples from their cats and dogs. The swabs were used in PCR tests, which provide evidence of current infection, and the blood samples were tested for antibodies, which provide evidence of past infection.
About 156 dogs and 154 cats from 196 households were tested in total. The researchers found that six cats and seven dogs (4.2 per cent) had positive PCR tests and 31 cats and 23 dogs (17.4 per cent) tested positive for antibodies. "If you have COVID-19, you should avoid contact with your cat or dog, just as you would do with other people," said Els Broens, from Utrecht University. "The main concern, however, is not the animals' health -- they had no or mild symptoms of COVID-19, but the potential risk that pets could act as a reservoir of the virus and reintroduce it into the human population," Broens said in a statement.
Eleven of the 13 owners whose pets had tested positive agreed for them to undergo a second round of testing one to three weeks after they were first tested. All 11 animals tested positive for antibodies, confirming they had had COVID-19. Three cats still had positive PCR tests and were tested for a third time. All the positive animals eventually cleared the infection and tested negative for the virus. Eight cats and dogs that lived in the same homes as the positive pets were also tested again at this second stage to check for virus transmission among pets.
The study found that none tested positive, suggesting the virus was not being passed between pets living in close contact with one another. The research shows that COVID-19 is highly prevalent in pets of people who have had the disease, with pets in 40 out of 196 households (20.4 per cent) having antibodies for the virus. The study was presented at the European Congress of Clinical Microbiology & Infectious Diseases held online this year due to the pandemic.
The researchers said that with other studies showing COVID-19 rates to be higher in pets that have been in contact with infected people, than in pets without such contact, the most likely route of transmission is from human to pet, rather than the other way round. "Fortunately, to date no pet-to-human transmission has been reported. So, despite the rather high prevalence among pets from COVID-19 positive households in this study, it seems unlikely that pets play a role in the pandemic," Broens added.
