Cats and dogs may need Covid vaccine to curb infections, scientists say

Experts warn continued evolution of virus in animals followed by transmission to humans ‘poses significant long-term risk to public health’

A group of scientists have suggested cats and dogs may need to be vaccinated against Covid-19 to curb the spread of the virus (iStock/Getty Images)

Cats and dogs may need to be vaccinated against Covid-19 to curb the spread of the virus, according to a group of scientists.

Coronavirus can infect a wide range of species including cats, dogs, mink and other domesticated species, experts from the University of East Anglia (UEA), Norwich-based research facility the Earlham Institute and University of Minnesota have said.

In an editorial for the journal Virulence, they warned that continued evolution of the virus in animals followed by transmission to humans "poses a significant long-term risk to public health".

"It is not unthinkable that vaccination of some domesticated animal species might... be necessary to curb the spread of the infection," they wrote.

Last year, Denmark's government culled millions of mink after it emerged hundreds of Covid-19 cases in the country were linked with coronavirus variants associated with farmed mink.

One of the editorial's authors, Cock van Oosterhout, professor of evolutionary genetics at UEA, said dogs and cats can contract coronavirus but there are no known cases in which there has been spillback to humans.

"It makes sense to develop vaccines for pets, for domestic animals, just as a precaution to reduce this risk," he said.

"What we need to be as a human society, we really need to be prepared for any eventuality when it comes to Covid.

"I think the best way to do this is indeed consider development of vaccines for animals as well.

"Interestingly the Russians have already started to develop a vaccine for pets, which there's very little information about."

Kevin Tyler, editor-in-chief of Virulence, said: "Cats are asymptomatic but they are infected by it and they can infect humans with it.

"The risk is that, as long as there are these reservoirs, that it starts to pass as it did in the mink from animal to animal, and then starts to evolve animal-specific strains, but then they spill back into the human population and you end up essentially with a new virus which is related which causes the whole thing all over again."

He said that while mink were culled in Denmark, "if you were thinking about domestic animals, companion animals, then you might think about whether you could vaccinate to stop that from happening".

He added: "It's not an obvious risk yet."

Prof van Oosterhout and Prof Tyler wrote the editorial along with director of the Earlham Institute Neil Hall and Hinh Ly of the University of Minnesota.

In their editorial, the scientists wrote: "Continued virus evolution in reservoir animal hosts, followed by spillback events into susceptible human hosts, poses a significant long-term risk to public health.

"SARS-CoV-2 can infect a wide range of host species, including cats, dogs, mink and other wild and domesticated species and, hence, the vaccination of domesticated animals might be required to halt further virus evolution and spillback events.

"Whilst the vaccination campaigns against SARS-CoV-2/ Covid-19 are being rolled out worldwide, new virus variants are likely to continue to evolve that have the potential to sweep through the human population."

They said that more transmissible virus strains, such as the UK variant, require more people to be vaccinated to keep coronavirus under control.

"Vaccination against a viral pathogen with such high prevalence globally is without precedent and we, therefore, have found ourselves in uncharted waters," they wrote.

The scientists have called on governments to consider the continued use of strict control measures such as masks and social distancing as the only way to reduce the evolution and spread of new Covid-19 variants.

Additional reporting by PA