More cats may be COVID-positive than thought, scientists suggest

WUHAN, China — A new study out of “ground zero” for the coronavirus pandemic reveals troubling news for cat owners out there. Researchers in Wuhan, China say more cats may be COVID-positive than most assume right now. While the felines seem to be doing a good job fighting off the infection and remaining asymptomatic, they are at risk of re-infection.

Conducted at the Huazhong Agricultural University in Wuhan, researchers collected blood samples (and nasal/anal swabs) from 102 local cats earlier this year as the coronavirus first emerged (January – March 2020). The cats came from a variety of places. Many (46) had already been abandoned by animal shelters, another 41 came from animal hospitals, and 15 were from people who had tested positive themselves.

Among all those cats, 15 showed the presence of COVID-19 antibodies in their blood. Of those 15 cats, 11 displayed actual neutralizing antibodies. That is, proteins which can successfully block the coronavirus from infecting a host (in this case, the cats).

‘Infections probably due to contact with SARS-CoV-2 polluted environment’

It’s noteworthy that not a single cat tested positive for COVID, nor did any display obvious coronavirus symptoms. Also, according to periodic check-ins on the cats, none of the 102 examined felines have passed away as of today.

The three cats with the most antibodies had all come from an owner who tested positive for COVID-19, but the study’s authors say they’ve also found evidence that some examined cats were infected by other felines, not humans.

“Although the infection in stray cats could not be fully understood, it is reasonable to speculate that these infections are probably due to the contact with SARS-CoV-2 polluted environment, or COVID-19 patients who fed the cats,” comments lead study author Meilin Jin in a release. “Therefore measures should be considered to maintain a suitable distance between COVID-19 patients and companion animals such as cats and dogs, and hygiene and quarantine measures should also be established for those high-risk animals.”

Can cats have a coronavirus infection more than once?

The research team did their best to closely examine and analyze the full spectrum of antibody reactions observed in the cats. One observation of particular note is the revelation that the cats’ immune reaction to the coronavirus appears to mimic, or at least resemble, typical immune reactions to seasonal coronavirus infections. This suggests, researchers say, that cats can indeed be reinfected with coronavirus.

Moreover, similar antibody reactions have been seen in humans. With this in mind, the authors say their work should be used as a “reference for the clinical treatment and prevention of COVID-19.”

“We suggest that cats have a great potential as an animal model for assessing the characteristic of antibody against SARS-CoV-2 in humans,” they write.

“Retrospective investigation confirmed that all of antibody positive samples were taken after the outbreak, suggesting that the infection of cats could be due to the virus transmission from humans to cats. Certainly, it is still needed to be verified via investigating the SARS-CoV-2 infections before this outbreak in a wide range of sampling,” Jin concludes.

The study is published in Emerging Microbes & Infections.