A highly transmissible variant of the coronavirus is spreading across Canada, causing a new wave of infections, even among those who have recently recovered from COVID-19.
The BA.5 sub-variant of the Omicron, and to a lesser extent the BA.4, is largely behind the last wave – the seventh since the Pandemic and the third since the arrival of the Omicron.
Both have shown an ability to evade the protection offered by a previous infection.
“The BA.5 subvariant has mutated to the point where your body doesn’t recognize it and people get reinfected,” said Dr. Fahad Razak, an internist at St. Michael’s Hospital in Toronto and scientific director of Ontario’s COVID-19 Science Advisory table.
“So you’re seeing this additional spike starting in Ontario, and now it’s started in other parts of Canada.”
The good news is that data coming out of countries where BA.4 and BA.5 have already taken hold, like South Africasuggest that they are no more severe than previous Omicron subvariants or more likely to result in hospitalizations.
However, the large number of people who are likely to become ill (especially those who are vulnerable to serious illness), together with overburdened emergency departments in many parts of the country is a cause for concern, Razak said.
“Something that’s a little less severe but infects a lot of people means … that the total number of Canadians getting sick — very sick and potentially dying — could actually be higher,” he said.
Razak pointed to a scientific analysis conducted for the star of torontowhich found that as of mid-2021, Omicron was more deadly for Ontarians age 60 and older than the previous two waves combined because of the high volume of infections.
Razak is now among a chorus of experts and public health officials urging the Canadian public to get a booster to protect against more serious illnesses.
“That third dose is incredibly valuable,” he said. “It gives you protection against severe disease and will give you at least a few weeks, maybe a few months, of protection against even getting infected at all.”
“So if you haven’t had that third dose, there’s no better time than now.”
Keeping your vaccination ‘up to date’
Canada had one of the highest vaccination rates in the world after two doses, but uptake of subsequent vaccines was slower. Across Canada, more than 40 percent of eligible Canadians have not yet received a third dose.
Razak says the message around what constitutes “fully vaccinated” needs to change given the evolution of the virus and the waning immunity of vaccines over time.
“Probably a better way to describe it is keeping your vaccines up to date, rather than being fully vaccinated, in the face of a virus that mutates rapidly.”
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Sarah Otto, an expert in modeling and evolutionary biology at the University of British Columbia, has been tracking changes in the coronavirus and says it has changed rapidly.
BA.4 and BA.5 are likely to soon become the dominant strains across the country, she said.
Those subvariants tend to infect the upper respiratory tract, she said, and “not as deep into our lungs.”
“However, there is still significant mortality, especially if you have had no immunity at all,” Otto said.
She also recommends that those eligible for a third dose get one as soon as possible, and those who are older or more vulnerable to serious illness should get a fourth.
“Why play Russian roulette with your health and the health of your loved ones? Get a booster if you can,” she said. “This will protect yourself and those around you.”
There are no upcoming restrictions
This week, officials in Ontario, Quebec and British Columbia acknowledged that their provinces have entered another wave of COVID-19.
In Quebecthe number of COVID patients in the province’s hospitals rose from 1,007 to just under 1,500 in the past month — an increase of more than 50 percent.
Hospitalizations are also rising each week in British Columbia in Ontariowhere about 60 percent of confirmed cases of COVID-19 result from BA.5.
Neither province has said public health restrictions are coming, at least not in the summer.
“We are no longer at a point where we are imposing things when people are well aware of the risks. It’s just a matter of reminding them,” Quebec Health Minister Christian Dubé said Thursday.
Quebec Health Minister Christian Dubé, right, says that although cases of COVID-19 are rising again in the province, he does not foresee a reimposition of public health restrictions. (Jacques Boissinault/The Canadian Press)
For now, it’s up to the public to make an informed choice, more than two years into the pandemic, said Kathryn Hankins, co-chair of the Canadian Task Force on Immunity to COVID-19 and a professor of epidemiology at McGill University, in an interview with CBC Montreal’s Radio Noon.
“We’re in a different scenario, with a highly transmissible virus and no mandates really in place,” she said. “We are in a difficult time.”
For his part, Razak urged people to wear a mask if gathering indoors in large groups and to meet outside whenever possible.
If cases rise again in the fall, he said, the threshold for reinstating the mask mandate should be low.
“It’s about using things like masks to prevent the more aggressive steps of restrictions or closures that were taken earlier in the pandemic,” he said.
And despite the new increase in cases, Razak said there are reasons to be hopeful.
“We now have a lot of immunity in our population, which helps protect against severe disease,” he said. “We have vaccines that continue to be remarkable even though all these mutations are happening. [They] they continue to be very protective against severe disease if we use them.”
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