Possible case of deer-to human Covid infection identified in Canada

Canadian researchers believe they have found the first instance of a deer passing the coronaviruses to a human, warning that more monitoring of wildlife is needed to prevent further mutations from developing and spreading undetected.

Scientists say at least one case of Covid-19 in humans can be traced to a strain of the virus found in deer.

White tail deer have been found with Covid in northeastern regions of the United States and central provinces of Canada. While deer aren't typically seen as a species that can easily pass on the virus to humans, experts speculated that transmission was possible.

Canadian scientists took samples from hundreds of white tail deer that were hunted in southwestern Ontario. The 17 deer that were positive for the coronaviruses were found to have a new and highly diverging lineage.

The virus does not have the same resemblance to strains currently circulating in human populations. The closest genetic relative to the strain came from samples taken from humans and mink in Michigan two years ago, according to one of the paper's authors.

The researchers compared the genetic makeup of the coronaviruses found in deer and humans in the region.

One resident had a similar strain of the virus and had been in contact with deer. The authors said it was difficult to fully understand the genetic relationship between the strains, but the timing and location of the infection suggested a deer was the probable source.

The scientists aren't sure how the deer contracted the virus, but the variant circulating in the population suggested that the vaccine wouldn't work.

It's reassuring that we found no evidence of further transmission during a time when we were doing a lot of sampling.

The experts have been concerned that the virus could cause problems in certain animals.

Canada's public health agency said there was no indication that the virus had spread to humans and that it was probably an isolated case.

The agency said that until we know more, people who hunt, trap or work with wildlife should take precautions.