National Post (National Edition)
VIRUS OUTPACES VACCINATIONS AS FIELD HOSPITAL OPENS
Fast-spreading COVID-19 mutant is 2021's `nightmare'
A mutated COVID-19 virus capable of spreading more easily and quickly that has plunged England and Scotland into bleak new national lockdowns is gaining a foothold in Canada. Will it do here what it has done in the United Kingdom — and rapidly overtake the current circulating strain?
Ontario on Monday confirmed three new cases of the “super-contagious” viral variant officially known as B. 1. 1. 7, bringing the province's total to six cases, all tied to travel outside the country. British Columbia, Alberta and Quebec have reported one confirmed case each.
The more transmissible variant has spread across England since it was first detected in September. Cases are being reported in dozens of other countries, including the United States, Denmark, Netherlands, India, Turkey, Vietnam and Germany.
Another mutated strain, so far not detected in Canada, is being blamed for a surge of COVID-19 cases in South Africa.
There’s no evidence the U.K. strain is more lethal or is causing greater rates of hospitalizations or deaths. And viruses like the SARSCoV-2 pathogen that causes COVID-19 accumulate small, random mutations all the time.
What’s worrisome is the U.K. variant emerged with an unusually large number — 17 — of mutational changes, particularly in the spike protein it uses to latch to and enter human cells, making people much more likely to get infected.
The South African variant also carries multiple spike mutations, but so far it hasn’t been associated with worse symptoms. And World Health Organization officials said there is no sign it’s more contagious than the one spreading fast in Britain.
“Genetic diversity of this lineage has changed in a manner consistent with exponential growth,” a team led by Imperial College London researchers warned in a preprint. While data are limited, the U.K. variant is thought to be 40- to 70-per-cent more transmissible, increasing the basic reproduction number — the average number of people each infected person goes on to infect — by between 0.4 and 0.7.
Canada’s reproduction number is at or near 1.0. It needs to be below that for cases to start falling.
The higher infection levels in Britain happened despite high levels of social distancing. The mutated virus is also infecting a larger share of under-20s.
“Viral evolution can’t be bargained with,” Amir Attaran, a biologist and professor of law and medicine at the University of Ottawa, said in a recent Twitter thread. The variant is a “2021 nightmare” and there are only two ways out of the nightmare, according to Attaran — an Atlantic-Canada, or even British-style lockdown to buy time, and “express vaccinations” come April when supplies become more plentiful.
Vaccines still appear effective against the mutant strains.
“The growth rate is going up by 40 to 70 per cent and the best point estimate is in the low 50s,” Attaran said. “By god, do I hope that’s wrong.”
Canada’s ban on passenger flights from the U.K. imposed in late December is set to expire midnight Wednesday. “Although we slammed the door as quickly as we knew, it was already too late,” Attaran said. “The variant is within Canada and circulating in the community, which means it is 100 -per-cent, positively inevitable that it will displace the existing virus.”
The B.1.1.7 strain is more efficient at transmitting. “It of course is going to, over time, displace strains that are less efficient at transmitting. That’s just how viral ecology works,” Attaran said.
“If you believe, as I think nearly all of us would, that more sick and more dead is simply not an option, then something has to change,” Attaran said, meaning further tightening our circles. “There is no choice.”
Warning the coming weeks will be the “hardest yet,” U.K. Prime Minister Boris Johnson announced a return to a spring-style lockdown in Britain that is expected to last to mid-February.
Within the span of about three months, the variant was able to overtake the circulating strain in the U.K. “Time is of the essence for us,” said University of Manitoba virologist Jason Kindrachuk. The variant hasn’t overtaken the circulating strain in Canada, at least from the data accrued so far.
The Canadian COVID Genomics Network is developing methods to flag samples that might potentially have the U.K. virus, said executive director Dr. Catalina Lopez-Correa. “We don’t know exactly how prevalent” the variant is in Canada, she said.
The U.K. has roughly double the population of Canada, on a much smaller landmass, Kindrachuk said. Still, “we have to look at the U.K. data and certainly start to think, what is our plan to try and reduce transmission and what does this potentially mean for us in the coming months?”
The question is, if the viral variant starts circulating more broadly, how quickly could it overtake the dominant strain? “Maybe we won’t see as rapid dissemination,” said Kindrachuk, who is a Canada Research Chair in emerging viruses at the U of Manitoba. “But certainly in places with higher population density, like Ontario and Quebec and Vancouver and B.C’s lower mainland, there is that concern.”
The nine cases confirmed so far through genomic sequencing have been in travellers or their contacts, Canada’s chief public health officer Dr. Theresa Tam said Tuesday. “As far as we know, we’re not expecting that there are large numbers of contacts related to these cases,” she said, partly because of the mandatory 14day quarantine for travellers entering the country.
“But there is always a risk of a virus that can transmit in all sorts of hidden ways to accelerate in different places,” Tam said.
It goes back to masking, distancing, not being in close settings for long periods of time, avoiding groups of people, Tam said. “You’ve really got to double down on your efforts with a more transmissible virus,” Tam said. If spread accelerates, “it means that there will be more public health measures that might be needed,” she added.