Covid transmission from human-to-cat is possible, scientists confirm
Two cases of human-to-cat transmission of Covid-19 have been identified by researchers from the University of Glasgow as part of a screening programme.
The cats, of different breeds, were living in separate households and displayed mild to severe respiratory signs. Researchers believe both pets were infected by their owners, who had Covid-19 symptoms before the cats became unwell.
The study, published in the Veterinary Record, said there is currently no evidence of cat-to-human transmission or that domestic animals can play any significant role in the epidemiology of human infections.
However, the scientists said domestic animals could potentially act as a “viral reservoir”, allowing continued transmission, and said it is important to improve understanding of whether pets can play a role in infecting humans.
“These two cases of human-to-animal transmission, found in the feline population in the UK, demonstrate why it is important that we improve our understanding of animal SARS-CoV-2 infection,” lead author of the study Margaret Hosie, and professor from the MRC-University of Glasgow Centre for Virus Research, said.
“Currently, animal-to-human transmission represents a relatively low risk to public health in areas where human-to-human transmission remains high,” The professor said. “However as human cases decrease, the prospect of transmission among animals becomes increasingly important as a potential source of SARS-CoV-2 reintroduction to humans.”
“It is therefore important to improve our understanding of whether exposed animals could play any role in transmission.”
One cat, a four-month-old Ragdoll kitten from a household in which the owner developed symptoms that were consistent with the Covid-19 at the end of March 2020, although they were not tested.
The kitten was taken to a vet with breathing difficulties in April last year, but its condition worsened and it later had to be put down. Lung samples taken post-mortem revealed damage consistent with viral pneumonia.
It is not known whether cats with Covid-19 could naturally transmit the virus to other animals, or back to humans. Yet, scientists believe the cases are likely to be the tip of the iceberg when it comes to human-to-animal transmission, as animal testing is limited.
Global reports
Reports of cats, both big and domestic, catching Covid-19 have swirled since the pandemic began.
Cats in Hong Kong, Belgium, the US, France and Spain which reportedly tested positive for Covid-19, also known as SARS-CoV-2, were presumed to be infected by their owners.
“Cats and dogs have been reported to be infected. This is a high-quality study, including whole-genome sequencing to confirm transmission links,” head of the Department of Veterinary Medicine at the University of Cambridge, Professor James Wood, said.
“These are important and interesting findings, adding to the body of evidence that humans can infect their pets, in some cases, as here, leading to clinical disease in the animals.”