Coronavirus variants, resistant to existing public health restrictions, near dominance in Quebec

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Coronavirus variants, resistant to existing public health restrictions, near dominance in Quebec
The warm weather on Thursday drew people outside in Montreal despite provincial restrictions on gathering. (Ryan Remiorz/The Canadian Press - image credit)
The warm weather on Thursday drew people outside in Montreal despite provincial restrictions on gathering. (Ryan Remiorz/The Canadian Press - image credit)

Variants of the virus behind COVID-19 are on the verge of becoming dominant in Quebec, with past and existing government measures to control spread not enough to contain the more contagious virus strains, Quebec's public health institute said Friday.

"There's a variant wave moving that is getting bigger," said Gaston De Serres, an epidemiologist with l'Institut National de Santé Publique du Québec (INSPQ).

De Serres said the spread of so-called variants of concern had begun to accelerate weeks ago, when the Quebec government's public health measures were more strict.

That means those measures "were insufficient to control the variants," he said, which means further action is required to prevent the variant wave from becoming an overall third wave.

In the meantime, the Quebec government has lowered the alert level in several regions and relaxed other rules: spas and gyms in Quebec's red zone regions were allowed to open as of Friday; places of worship can welcome up to 250 people, depending on their capacity; and high schools will return to in-person classes next week.

The timing of these changes worries Dr. Raymond Tellier, an infectious diseases specialist and medical microbiologist who is also an associate professor at McGill University.

"It's unfortunate that we seem to be creating circumstances that may lead to triggering super-spreading events and outbreaks," he said.

Watch| Premier François Legault getting his first dose of vaccine

Quebec Premier François Legault, speaking to media after getting a first vaccine shot at the Olympic Stadium, said officials are keeping a close eye on the situation, and it is possible that new public health measures will be adopted if needed.

"The next weeks are critical," said Legault, invoking a "huge wave," should Quebecers let their guard down.

"The variants are more contagious. It's important that you are all careful."

Variants are already dominant in Quebec City and the Lower Saint-Lawrence, Abitibi-Témiscamingue and Outaouais regions, according to the INSPQ. They are close to making up most new cases in greater Montreal.

What does it mean?

Left unchecked, the variants will continue their exponential growth, De Serres said. Many older, more vulnerable people are now protected by vaccines, but significant transmission in younger age groups would lead to a higher number of severe cases and hospitalizations.

"Each time someone gets an infection, it's a little bit of a game of Russian Roulette," Tellier said. "Even if you are young and healthy, the risks of complications are low but they are not zero."

Data from other countries has shown that the variants are "not just more contagious but more likely to cause severe symptoms," said Mathieu Maheu-Giroux, an assistant professor in the department of epidemiology and occupational health at McGill University who works with the INSPQ.

A briefing prepared by Ontario's science advisory table — expected to be made public early next week and based on data between December and March — is expected to show that variants increase death and hospitalization risk by 60 per cent and the risk of being admitted to intensive care by 100 per cent .

What can be done?

Although the variants will soon become dominant, the arrival of a third wave is not inevitable, De Serres said. But avoiding it would require either stronger adherence by the population to public-health measures, or additional government restrictions.

The idea of more restrictions may be unpalatable to some Quebecers who by now are experiencing "pandemic fatigue," De Serres acknowledged.

Premier Legault said if measures are too intense, people may stop following the rules altogether.

The question public health and government officials must wrestle with is what a third wave would look like in the context of the vaccination campaign, in terms of hospitalizations, deaths and impact on the health-care system.

Data released Thursday by the provincial health institute, known as the INESSS, shows new cases have dropped among those 70 and older, and the average age of people hospitalized for COVID-19 is trending younger — both trends expected now that a majority of people aged 70 and over have now received a first vaccine dose.

Legault said the government is betting that there will not be a sharp increase in hospitalizations given the rate at which people 65 or older — the group that makes up most of the severe cases — are getting their shots.

Similarly, after Quebec reported a rise in new cases Friday, Health Minister Christian Dubé said on social media an increase in cases had been expected. But he said "what matters to us is that this increase in cases does not translate into an increase in hospitals, as it did in January."

Why is it happening?

For many health-care experts, the dominance of variants in Quebec has been a question of when, not if.

The rise of the so-called variants of concern is not a surprise, because by definition a more contagious strain will spread more easily.

Variants already account for the majority of new cases in Ontario and Saskatchewan and are expected to become dominant in B.C. within weeks.

Quebec data indicates the variants have a "transmission advantage" of 30 to 50 per cent over the historical strains, said Maheu-Giroux, though that range is "probably a slight underestimate."

The INSPQ has been tracking the variants' effective reproduction number, Rt, which is a measure of how fast the disease is spreading. That number is currently 1.31, which means 100 people with a variant strain would infect another 131 people.

For the original strains of COVID-19, Rt is 0.92, meaning the spread has been under control.