Several new studies show that many white-tailed deer in the northern United States have contracted COVID-19, with potential implications for the fight against the pandemic.
And while the same has yet to be found in Canadian deer, scientists say finding the virus in wildlife could mark the end of any hope of completely eradicating COVID-19. in humans.
“Any disease that infects more than one species,” says Scott Weese, a veterinary infectious disease specialist with the Ontario College of Veterinary Medicine and director of the Center for Public Health and Animal Diseases. I cannot eradicate.
Two recent US studies have found evidence that COVID-19 is present in deer populations. In one study, researchers sampled 283 deer in Iowa between April 2020 and January 2021 and found that a third of them had evidence of COVID-19 infection. These infections are likely due to multiple transmissions from human to deer and deer to deer, the researchers say.
Spread of COVID-19 in mink
Another US Department of Agriculture study found antibodies to the SARS-CoV-2 virus in 40% of the 385 wild deer they sampled in 2021 from four states: New York, Michigan , Pennsylvania and Illinois. These antibodies suggest the deer were exposed to COVID-19 at some point, the researchers write.
The scientists said they tested deer knowing that the animals are biologically susceptible to infection with the virus and can exhibit prolonged shedding, are social animals and often live in close proximity to animals. urban center.
Jeff Bowman, a wildlife scientist with the Ontario Ministry of Northern Development, Mines, Resources and Forestry, said Canadian scientists have been following the US research with interest. .
They are looking into the possibility that wild animals, including deer, could become a “reservoir” for SARS-CoV-2, he said.
“If the virus is circulating in a wildlife population, it could persist in that population and become a source of re-infection to humans,” he said.
Nova Scotia pays for mink COVID-19 vaccine, BC says no before shutting down industry
It’s also possible that viruses circulating in animals could generate new variants, Weese said.
“The more they transmit, the more they mutate because the more they reproduce, the more random errors can happen,” he said. “And when they switch to a different species, that’s probably more likely to happen because they’re adapting to that species a little bit.”
That’s not necessarily dangerous to humans, he said, but what health professionals don’t want to see is that the virus mutates in deer and can still infect humans.
“It’s possible it’s different enough that our immune systems won’t recognize it either,” he said, adding that this is a low-risk situation, but not impossible.
A group of Canadian organizations, including the Public Health Agency of Canada, the Ontario Ministry of Health and the Canadian Wildlife Health Center, sampled a variety of animals – including ferrets, raccoons, and raccoons. skunks and bats – and so far there is no result Bowman says any evidence of the virus, even though ferrets on BC farms have been infected with COVID-19. They are still collecting samples of muskrats, otters, beavers and white-tailed deer.
BC announces plan to phase out ferret farms gradually due to concerns about COVID-19
It is possible that if deer in the northern United States have been infected, some Canadian deer could also be infected, Weese said, at least in places where the countries share a land border.
“Deer don’t care where they’re going,” he said, though he is tracking the end results of studies in Canada.
Weese said researchers aren’t sure how the virus got into the deer in the first place – conjectures include through deer farms or possibly wild deer feeders – and they It is also unlikely that a person can contract COVID-19 from an infected deer.
“It’s probably pretty unlikely,” he said.
Most people do not come into close contact with deer, although those who work with captive deer may be at risk.
We could see an increase in diseases like COVID-19 due to climate change
The other risky group, he said, could be the hunters.
“An injured deer is breathing and they are approaching it, that is doable,” he said, as well as being able to handle the deer during slaughter.
Wisconsin has issued guidance to hunters on how to protect themselves from the possibility of infection, including wearing a mask while cleaning carcasses and washing hands, tools, and surfaces that come in contact with animals after. there. However, the state notes that the CDC says there is currently no evidence that wildlife can be a source of infection for people in the US.
Quebec Zoo hopes to vaccinate wildlife against COVID-19 in the coming weeks
“The greatest risk of contracting SARS-CoV-2, from transmission of that virus, is person-to-person,” says Bowman. “And we think the risk of transmitting that virus from animals to humans is lower. For instance, there is no evidence that a virus is transmitted through food preparation or food consumption, such as from wild game.”
Scientists need to think more broadly about the impact of viruses that are transmitted between animals and humans on this and the next pandemic, Weese said.
“We are one big ecosystem and the virus doesn’t care… are we humans or dogs or cats or what we call animals.”
View links »
© 2021 Global News, a division of Corus Entertainment Inc.