according to researchers’ latest tally.
In most cases, humans infect animals, and animals don’t transmit the virus back to humans. But scientists have expressed concerns about recent research that shows some animals – such as mink and deer – appear to be able to spread the virus to humans.
In addition, the virus will likely continue to circulate in wild animals, which could lead to new mutations, some of which may make the virus less susceptible to people’s immunity from current vaccines. Researchers are calling for better surveillance of animals, especially in the wild, to track any new variants.
“It could be evolving in hosts we are not aware of,” Eman Anis, PhD, an assistant professor of microbiology at the University of Pennsylvania, Philadelphia, told the Philadelphia Inquirer.
Scientists have identified the virus in a growing list of animals, according to the Centers for Disease Control and Prevention, including cats, dogs, ferrets, gorillas, hamsters, hippos, hyenas, mice, otters, pigs, rabbits, and tigers. In many cases, humans spread the coronavirus to pets at home or to wildlife in zoos and sanctuaries.
In the study, published in bioRxiv, researchers identified a person who tested positive after close contact with infected white-tailed deer. The coronavirus had evolved dozens of mutations not found in other strains.
Even with the changes, the virus they found doesn’t appear different enough to evade current vaccines, the researchers reported. The vaccines target the spike protein on the outside of coronavirus cells, and the mutations that happened in deer occurred elsewhere in the virus.
At the same time, scientists have noted that this points to the need to step up monitoring in wild animals before mutations become a problem.
“This is no need to panic, but this is not something we can ignore,” Suresh Kuchipudi, PhD, a professor of veterinary and biomedical sciences at Pennsylvania State University in University Park, told the Inquirer.
Dr. Kuchipudi, who wasn’t involved with the Canadian study, has done other studies that found COVID-19 in deer. As the coronavirus continues to circulate in deer, more mutations will arise, he noted.
“It’s hard to predict what evolution’s going to come up with,” Frederic Bushman, a microbiology professor at the University of Pennsylvania, told the Inquirer.
“The virus will probably change different ways in different animals. Some of them probably won’t infect humans as well,” he said. “But the fear is that maybe some new one will come along that does infect humans well.”
A version of this article first appeared on WebMD.com.