It took two years, but researchers are now convinced that cats — although highly unlikely — can transmit SARS-CoV-2 to humans after a vet in Thailand caught the virus from a sneezy pet tabby who tested positive with the virus. This is the "first solid evidence" of a cat-to-human transmission of SARS-CoV-2, the virus that causes Covid-19, according to American Scientific.
The feline finding, published in Emerging Infectious Diseases on 6 June, came about by accident, says co-author Sarunyou Chusri, an infectious-disease researcher and physician at Prince of Songkla University in Hat Yai, southern Thailand. In August, a father and son who had tested positive for SARS-CoV-2 were transferred to an isolation ward at the university's hospital. Their ten-year-old cat was also swabbed and tested positive. While being swabbed, the cat sneezed in the face of a veterinary surgeon, who was wearing a mask and gloves but no eye protection.
Three days later, the vet developed a fever, sniffles and a cough, and later tested positive for SARS-CoV-2, but none of her close contacts developed COVID-19, suggesting that she had been infected by the cat. Genetic analysis also confirmed that the vet was infected with the same variant as the cat and its owners, and the viral genomic sequences were identical.
But researchers say cat-to-human transmission is "probably rare," according to Scientific American, as "infected cats don't shed much virus, and shed for only a few days," according to University of Hong Kong virologist Leo Poon. Other animals known to have passed the virus on to humans in very rare circumstances include mink, pet hamsters, and white-tailed deer. Of course humans are the main, nearly exclusive spreaders of Covid-19.