The Pestilence Threatening Us

"Even just based on waning immunity the time since the average person had their last infection or their last booster, a wave was expected. As usual, it's hard to say, will this be a big wave? Will it be a small wave. For sure it's a wave of some kind."

"[Science magazine warned one or more of several highly immune strains of SARS-CoV-2 -- BA.2.785/2. BQ.1.1, BF.7] may well cause big, new COVID-19 waves this fall and winter."

"It's [natural selection] increasing evidence that they [variants] are doing something, and what that something is, is probably to evade immunity. So they're even better at reinfecting people."

"I don't want to underplay what this virus has been putting us through -- it clearly is able to evolve in all kinds of different directions and surprise us. Bit it's encouraging that we are seeing the same mutations, repeatedly. Which suggests, at least for now, a limited supply of adapted mutations." 

"My crystal ball is my fantastic other colleagues with CoVaRR-Net [Canada's national Coronavirus Variants Rapid Response Network]. All credit to all these people who are sharing data and analyzing it."

"If you are a few months from your past infection or past vaccine, go get your booster. The more immunity we can get in the population, the less bad this wave will be in terms of overall transmissions and hospitalizations, and bad outcomes we want to avoid."

Jesse Shapiro, genomic evolutionary biologist, McGill University

A recent spike in cases and hospitalizations in the U.K., and a recent rise of the virus in wastewater levels in Ontario and Saskatchewan have scientists bracing for potential fall and winter waves. (Ben Nelms/CBC)

"They are basically less easily recognized by the antibodies that are in the majority of people right now."

"It's kind of saying that the virus is constrained. It's hobbled a little bit."

"Here in British Columbia, it's estimated we're under-reporting cases by 100-fold."

"COVID now, for almost all of us in Canada, is a disease our immune system recognizes."

"So when we get infected, if we don't have antibodies in our bloodstream currently, we have memory cells that remember this virus, that remember SARS-CoV-2, and kick into action."

"The bad news is that COVID is still rampant at the moment. So that first wave of protection -- having antibodies that recognize and prevent you from getting infected in the first place -- is still the one you want to go for."

Sarah Otto, evolutionary biologist, University of British Columbia 

Virologists are concerned new Omicron subvariants could potentially drive future COVID waves, especially given their concerning mutations. (Ben Nelms/CBC)

 

Throughout Canada, the state of public immunity has not reached the peak that health scientists would prefer it to be, leading the country's public health agency to appeal to the public to get "up to date" with their vaccines, now that new bivalent shots targeting the original SARS-CoV-2 strain along with the original BA.1 strain of Omicron are being made available. Bivalent vaccines that target the BA.4 and BA.5 strains currently along with BA. 2 the most prominent circulating strains in Canada have not yet been approved by Health Canada.

Quebec, Alberta and British Columbia are currently seeing infections and hospitalizations rising in a system already strained past the capacity of hospitals to absorb, and health care workers to manage. A gradual increase is being seen in cases in Ontario with the number of tests checking positive rising in the past two weeks. A new wave of COVID-19 is not only in the works, it's started. The pathogenic virus persists at a high rate of infection across the entire country. 

A vast convergence of evolution is transpiring, explained Dr. Shapiro an associate professor in McGill's department of microbiology and immunology. The same mutations or combinations of mutations are appearing in many of the variants and subvariants on key sites of the viral genome, allowing them to spread more rapidly, despite circulating within a highly immunized population. It is biology's natural selection that favours the same mutations repeatedly. New lineages or subvariants emerging from Omicron, a deep branch of the biogenetic tree of SARS-CoV-2.

Although none of the new variants are circulating at high levels in Canada, there is some concern that BQ.1.7, with a striking constellation of mutations increasing the capacity of the virus to evade antibodies, might sweep through populations as though no one has any immunity: "I don't think that's going to be the case, based on what I've seen so far. It's just helping the virus spread a little bit, not game-changer amounts. But it's too early to know for sure", hazarded Dr. Otto.

Omicron continues to mutate and produce new strains that have been shown to better evade immunity with the potential to drive new COVID waves. (Evan Mitsui/CBC)