Modelling predicts possibility of variant-related surge of cases in Montreal by March

·4 min read

MONTREAL — Quebec health officials said Wednesday there were no COVID-19-related deaths reported in the past 24 hours, but sobering new modelling suggested new variants of the novel coronavirus could surge in Montreal by March.

The modelling for the greater Montreal area released by the province's public health institute suggested a more contagious COVID-19 variant could be the dominant strain in the region in a few weeks.

The spread of variants, however, depends on how many cases are imported and how strongly people follow public health orders, such as limiting contacts, wearing masks, physical distancing and respecting quarantine rules when returning from travel, researchers told a technical briefing.

"The key right now, and the important message, is to have a good adhesion to the measures in place," said Marc Brisson, professor at Universite Laval's social medicine department and head of an epidemiological modelling group.

The researchers presented modelling based on a mutation that is between 1.2 and 1.8 times more contagious than the current strain, which corresponds roughly to the B.1.1.7 variant first detected in the United Kingdom. The modelling took into account the government's vaccination schedule to make its predictions.

The modelling provided a range of outcomes, from cases and hospitalizations remaining stable if few variants are imported and health orders are strictly respected, to infections shooting upwards if the opposite occurs.

Brisson said it's too soon to know which scenario will come to pass because the province doesn't have a complete portrait of how widely variants are circulating. He said vaccinations would likely help reduce the number of deaths among vulnerable seniors living in care, but he said many older adults living in the community have yet to receive shots.

As of Wednesday, there were 16 confirmed cases of variants of the novel coronavirus in Quebec, including 13 cases of the U.K. mutation. Health Minister Christian Dube said Tuesday there were another 86 suspected cases of variants in the province.

The modelling team found that the health orders imposed in early January, which included an 8 p.m. to 5 a.m. curfew, may have been enough to limit a rise in the number of new cases linked to a variant. However, the Quebec government chose to relax some measures on Feb. 8, including allowing non-essential stores to reopen.

"If a more infectious variant circulates in greater Montreal (ex. British variant B.1.1.7), the easing of measures on Feb. 8 could allow an increase in variant-related cases, and thus produce an increase in hospitalizations and deaths," the presentation read.

Brisson told the technical briefing that schools are likely to be the first place where a mutation will spread because of the high level of contacts in school buildings.

Meanwhile, Quebec reported 800 new cases of COVID-19 Wednesday and 14 new deaths attributed to COVID-19 — but none in the past 24 hours. That number is likely to change in the coming days as tallies are updated.

Health officials also reported a drop of five COVID-19-related hospitalizations, for a total of 766, and said there were 130 people in intensive care, a drop of four.

Brisson said a parallel study suggested the recent drop in cases was due to a significant reduction in the number of contacts people reported having in January. He said it's impossible to say if the downward trend is due specifically to the curfew or to other reasons, such as fear of rising cases or the fact that people had already gathered over the holidays.

Earlier Wednesday, Dube announced the government will make rapid tests available to private companies whose workplaces are vulnerable to COVID-19 outbreaks.

He said in a statement that companies seized with outbreaks can still request mobile rapid testing units that use standard PCR — polymerase chain reaction — tests, which are considered more reliable than rapid tests.

Quebec has been criticized for its slow rollout of rapid tests, which provide faster results than PCR tests and can help companies quickly detect infections and isolate cases.

This report by The Canadian Press was first published Feb. 17, 2021.

— With files from Sidhartha Banerjee.

Morgan Lowrie, The Canadian Press