A new study on the variant of COVID-19 permeating in England — and popping up in Canada — suggests the mutation isn’t any more likely to lead to hospitalization or death.
That’s good news, experts agree. But the same study reinforces what others before it have inferred — that this variant is “substantially” more transmissible.
While the data is still early and preliminary, it’s “not something we should dismiss,” said Dr. Isaac Bogoch, an infectious disease expert based out of Toronto General Hospital.
“Just because it doesn’t seem to be more deadly doesn’t mean it’s not a problem,” said Bogoch.
“It’s still not entirely clear to what extent its more transmissible, but, even so, a more transmissible virus would be challenging. It would pose significant challenges to a population.”
Early research
In the new technical report, released Tuesday, British researchers compared nearly 1,800 people infected with the new variant to the same number of those infected with the “regular” or “wild type” of COVID-19.
Their study found no significant difference in mortality or morbidity, nor in the likelihood of reinfection.
Of the 3,538 people who caught the disease between September and December, 42 were admitted to the hospital — 16 diagnosed with the new variant, 26 with the “regular” COVID-19 infection. Within 28 days of testing positive, 12 deaths were recorded among the group of new variant patients and 10 deaths among the “regular” COVID-19 group.
This is a positive — albeit preliminary — result, said Levon Abrahamyan, a virologist at the University of Montreal.
“A more pathogenic or lethal virus would be a disaster for us,” he said.
But the result doesn’t negate the risk of the coronavirus’s contagiousness, he added.
The U.K. researchers assert “with confidence,” that this variant has “substantially increased transmissibility.”
So why might this behaviour from a variant yield a similarly serious outcome? It has to do with exponential growth.
“An increase in something that grows exponentially (i.e. transmission) can have far more effect than the same proportional increase in something that just scales an outcome (i.e. severity),” Adam Kucharski, an epidemiologist with the London School of Hygiene and Tropical Medicine, wrote in a Twitter thread, which has since gone viral.
In other words, “it’s a numbers game,” said Bogoch.
“You would have more people infected, more people sick, which means there’s a greater number of people that are going to require hospital resources, which then means, sadly, a greater number of people who succumb to this illness,” he said.
From there, it only exacerbates a trend already seen during this pandemic, he said.
“Then there’s your health-care capacity,” he said.
“If you’re stretching that beyond capacity, you get a ripple effect of poor outcomes for non-COVID-19-related issues. That’s always troubling, too.”
Potential problems
At this point, scientists believe the variant is anywhere from 40 to 70 per cent more transmissible than the original strain. Since research is still underway, it’s not yet possible to pin down an accurate rate.
One study suggests the variant is 56 per cent more contagious than others. The U.K. government had previously said the variant appears to be as much as 70 per cent more transmissible.
Ultimately, there’s nowhere near enough evidence to know for sure, said Abrahamyan.
The studies so far — including the recent one out of the U.K. — have based their claims on controlled conditions in laboratories, said Abrahamyan.
“This frequently doesn’t work in real-world situations,” he said.
“These studies are valuable, definitely, but we can’t directly correlate or extrapolate this data into a human population quite yet. The small advantages this variant may have on (transmissibility) while in a control condition in a lab may not have any significant effect in the real world.”
That’s not to say some form of action shouldn’t be taken out of caution, Bogoch added.
As of Tuesday afternoon, the new variant spreading rapidly in the U.K. has been reported in British Columbia, Alberta, Ontario and, more recently, Quebec.
Flights from the U.K. to Canada have been suspended since Dec. 21 in an effort to curb further travel-related spread. It is expected to remain in place until at least Jan. 6, 2021.
“This is something that clearly needs attention,” Bogoch said, suggesting there could be room to tighten enforcement on the Quarantine Act in response to the new variant’s spread.
“But at an individual level, it changes nothing. We’re still going to put our masks on indoors, we’re still going to do physical distancing, and hopefully, we all accept the vaccine when it’s our turn.”
Vaccine?
The World Health Organization says there is not enough information to determine whether the new variants could undermine vaccines being rolled out internationally, but most experts are generally confident in the shots.
“It doesn’t appear this variant is going to have any significant impact on how effective vaccines are,” said Bogoch, adding that the vast majority of his peers believe the same.
Bogoch said a better understanding of how this variant — and any future variant — behaves is needed before we look to any potential changes to the vaccine.
It may be more transmissible, he said, but we don’t know to what extent.
“It appears the vaccine will work on this variant, but the definitive studies are underway,” he said.
“So in the meantime, vaccination programs will be an extremely important part of keeping this under control.”
Whether the current pace of vaccinations and testing in Canada is enough?
“We should be doing everything we can to scale that up as fast as possible. Not only to protect ourselves from these variants of COVID-19 but any variant of COVID-19,” he said.
“Until we have all the answers, we need to proceed with caution.”
— with files from The Canadian Press
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