Western Manitoba lab tracks SARS-CoV-2 in white-tailed deer with help from hunters

In a small laboratory in the industrial district of Dauphin, deer heads melt on the ground.

These heads are submitted as part of the provincial surveillance program for chronic wasting disease in deer, but for the past two years, technicians from the western Manitoba town have probed inside the nostrils and throats of deer to test for SARS-CoV-2. .

Richard Davis, a Manitoba Conservation biologist and manager of the province’s wildlife health program, is responsible for the program to prevent disease from affecting Manitoba’s wildlife populations.

He said after a US jurisdiction began testing for the virus that causes COVID-19 in samples of white-tailed deer, Environment and Climate Change Canada launched a study across the country asking agencies like the of Manitoba to begin testing deer for the virus.

Davis said his team sent 300 swabs last year, and three confirmed SARS-CoV-2 for a 1% positivity rate.

« It’s surprising because … the type of COVID that was in the deer was the alpha variant, the delta variant and a third variant that was only seen in the UK, » Davis said.

« Scientists and researchers are really wondering what’s going on there, and of course the concern is that if it becomes endemic in deer, are they going to pass it on to people. »

About 50 SARS-CoV-2 infections have been detected in deer across the country since October 2020, with Ontario, Alberta and British Columbia leading the way.

These infections could potentially impact humans, so researchers are using the hunting season to monitor the situation. This includes Jennifer Provencher, a research scientist with Environment and Climate Change Canada, who works at the National Wildlife Research Center in Ottawa.

« I think just pointing out the contribution and the collaboration with these hunters…for these programs to ensure that the deer are healthy and accessible, I think that’s really a really important point, » she said.

Earlier in the COVID-19 pandemic, animals such as cats and dogs contracted the virus from their family homes and other people they came into contact with, Provencher said.

These data prompted Environment and Climate Change Canada – along with provincial and territorial partners – to think about other species to which the virus causing COVID-19 could also be transferred.

“Can it get into deer? Can it get into birds? “, said Provencher.

The highest risk of contracting or being exposed to SARS CoV-2 2 is still human-to-human interaction, but many animals have interactions with humans. This is where Provencher first became interested in wild animals.

She says biologists like Davis tested white-tailed deer, mule deer, elk, and moose, and they found that white-tailed deer and mule deer were exposed to or had SARS-CoV-2 matching what Provencher’s colleagues in the United States found.

The positivity rate is below 5% in most areas, she said, but that’s over a two- to three-year sampling period.

In Manitoba, the western border accounts for most of the sampling because it is part of a screening program to see if chronic wasting disease is entering the province.

« It’s probably representative of that area. It’s probably not representative of the whole province, » Provencher said.

And just because SARS-CoV-2 doesn’t seem to have negative effects on deer doesn’t mean it doesn’t have an effect, she said.

« There are still potential ways to reduce survival. It could reduce fertility. There are many reasons why a disease can actually affect an animal, » Provencher said.

Viruses circulating in animals can also act as a reservoir, and it is possible that the virus continues to evolve.

« It’s still a big question mark for us. And so we don’t know if deer, especially in North America, will continue to circulate this virus and become a reservoir of viruses that could impact people. humans,” she said. .

« There is a comeback in humans that can really change the dynamics of the disease against humans. We don’t see it yet, but by following the population of deer in their SARS-CoV-2, we can see if it happens. »