An Omicron-like variant of the virus that causes Covid-19-appearing to be highly divergent from the circulating strains and protruding into the long branches of the virus’ family tree-was found in a population of white-tailed deer Canada. According to Ontario New research..
The same strain has been found in people in the same area who have confirmed contact with deer, but there is no evidence of persistent deer-to-human transmission and it is unlikely to pose an imminent threat to humans.
The researchers who first characterized what was called the Ontario WTD Clade evolved this line because it appeared to have been overlooked in the background of a pandemic and lasted almost a year unsampled. It is difficult to judge. They speculate that it spilled from humans to deer and returned to at least one human.
The new branch of the SARS-CoV-2 family tree has about 79 genetic changes that set it apart from the original strain of the virus first identified in Wuhan, China. About half (37) of these changes were found in animals, 23 of which were never found in deer.
“I think it’s actually a pretty important study, as the virus can evolve in animal reservoirs,” said J. Scottweise, a professor of infectious disease research at the University of Guelph, Canada. increase. Jump between animals and people.
Previously, according to Weeds, you might see the SARS-CoV-2 virus passing between humans and animals, but then it stops. After these spillovers or spillovers, there were no signs that it was persistent and changing in the animal population.
However, the closest virus relatives to the new clade date back 10-12 months to humans and mink in Michigan, which crosses the Ontario border.
“It went somewhere and changed between months and a year, and it seems most likely that it was in an animal. I just don’t know what species or place,” he reviewed the study. Says Weese, who was not involved in the study.
This study was submitted prior to a peer review on the preprint server BioRxiv.
In many respects, deer are the ideal host for SARS-CoV-2, Weese says. It is easy to get infected, but it does not get sick, it nests in groups, and the virus is easy to spread.
This new strain was detected during the hunting season. The hunters brought the deer they killed to the scientists who wiped and tested them.
Researchers say there is no evidence that this strain caused persistent deer-to-human or human-to-human transmission. However, the hunting season is over in the area, and the waves of Omicron are rushing in, further complicating surveillance.
Early laboratory experiments have suggested that antibodies produced in response to vaccination can easily knock down new strains, making this version of the virus less likely to pose an imminent threat. I am.
The question is what will happen in the future.
“I think most people thought it was causing a pandemic, but that’s true,” said research author Bradley Pickering, who is responsible for the special pathogens at the National Center for Alien Animal Diseases of Canada. “So now it looks like it’s circulating in wildlife.”
Staying a deer in North America can cycle and continue to change.
“You have that risk. It’s always there and you can always come back to people,” he said.
Researchers are trying to resume monitoring deer populations in order to continue to monitor the evolution of the virus, Pickering said.
When a deer becomes a true animal reservoir, it’s a difficult problem to solve, and it marks a new stage in the pandemic, Weez says.
“We need to go beyond a human-centric approach. An individual means an individual. It doesn’t mean a person,” Weese said. “It doesn’t matter if it circulates to 100 million people in fully vaccinated areas of the world or to 10 million deer in North America. It circulates and the virus circulates. That’s how mutations occur as they circulate and replicate. ”
When SARS-CoV-2 appears in populations of domestic animals such as mink, or in hamsters sold at pet stores in Hong Kong, it is often screened to contain the spread of the virus.
It is not possible if the virus is in a wildlife population.
There are also veterinary vaccines, but veterinarians use them for the same reasons they give to humans to prevent illness and prevent animals (such as zoo tigers) from becoming seriously ill or dying.
“Vaccines are not very effective in preventing infections,” Weese said. “We need animal vaccines that are better than human vaccines, and because animal vaccines are an old technology, they are a fairly high standard to set up.”