Laboratory studies suggest Covid-19 could be transmitted to numerous animals because its spike protein, by which it attaches to host cells, uses a protein found in many species.
Professor Sarah Edwards said: “There’s an urgent need for widespread surveillance, by testing samples, preferably non-invasively, from large numbers of animals, particularly pets, livestock and wildlife that are in close proximity to human populations.
“More laboratory experiments on small numbers of animals are unlikely to give us the evidence needed to be confident that certain species are entirely safe, making major surveillance work the only real option here.”
Her colleague Professor Joanne Santini said: “We need to develop surveillance strategies to ensure we don’t get taken by surprise by a large outbreak in animals which could pose a threat not just to animal health but to human health as well.”
She added that virus transmission in animal populations could “become irreversible” if left unchecked, which could “threaten the success of existing public health measures”.
The scientists said cats could pose a particularly high risk of spreading the virus between households because they are “efficient” carriers and roam far from home.
Infected mink which were being reared for their fur were found on 10 Dutch farms. The incident is the strongest evidence so far that animals pass the virus back to humans.
Experts believe that, once originally infected by humans, the outbreak among minks spread to different farms via wild cats. Antibody testing in the Netherlands found a significant minority of cats had been infected with the virus.
The US Centers for Disease Control and Prevention acknowledges that cats, dogs “and a few other” animals can be infected.
The body has updated its advice, telling people not to let their pets interact with other animals or people outside the house.
In New York, several lions and tigers at a zoo tested positive but all recovered fully.
Prof Santini said: “There is increasing evidence that some animals can catch SARS-Cov-2 from people, and might subsequently transmit it to other people, but we don’t know just how much of a risk this is as it’s an area of study that has not been prioritised.”
Testing for coronavirus in animals is most efficiently done through analysis of faecal matter.
The Lancet paper comes as staff at a chicken processing plant in north Wales were asked to self-isolate for two weeks after 58 cases of coronavirus were confirmed. Production was halted at the 2 Sisters Poultry factory in Llangefni, Anglesey.