COVID-19 and Cats: A New Study Supports Transmission Among Cats

A new study confirms that cats can be infected with SARS-CoV-2, the virus responsible for COVID-19, and that the virus can be transmitted between cats. However, these experimental findings should be viewed in context. The risk of infection in real-world situations remains low.   In early April, researchers at the Harbin Veterinary Research Institute published findings indicating that cats were susceptible to infection with the novel coronavirus, SARS-CoV-2, and could transmit it within their own species. One in three cats placed near cats inoculated with the virus tested positive. A few months later, following the identification of six cases of naturally infected cats, a new study by the University of Wisconsin School of Veterinary Medicine and the University of Tokyo reinforces this hypothesis. Japanese and American researchers show that three cats infected with COVID-19 in a laboratory were able to infect three other healthy cats.

Within five days, the virus appeared capable of infecting healthy cats housed with the infected cats. And five days later, they were still testing positive, which, according to the researchers, suggests they were likely still contagious.

  Blood tests also revealed the production of antibodies against SARS-CoV-2 as late as 24 days after infection. However, none of the cats showed any symptoms, and all cleared the virus completely. It should be noted, however, that the experimental setting does not necessarily reflect real-world conditions. The data show that viral transmission occurs easily among domestic cats, but the protocol used is far removed from reality. While this study highlights a higher probability of intraspecies transmission—even higher than in the previous study—the viral doses inoculated experimentally were five times higher. The animals were also housed in very small spaces. The amount of virus inoculated, as well as the confined space between the animals, likely greatly facilitated infection. These conditions therefore do not reflect realistic transmission. The response of Linda Saif, a world-renowned coronavirologist, in *Nature* magazine regarding the first study remains entirely relevant: “This suggests that the virus is not highly transmissible among cats.” “The results are based on laboratory experiments in which a small number of animals were deliberately given high doses of the virus, SARS-CoV-2, and do not represent real-world interactions between people and their pets.” The risk of natural infection due to exposure to SARS-CoV-2 remains fairly low, according to experts, and there is still no evidence that the virus can be transmitted from cats to humans, even though the reverse remains possible. Experts advise people with COVID-19 to minimize contact with their cats to avoid infecting them.