As provinces look at gradually lifting COVID-19 restrictions, masks should be among the last things to go, experts say, even with high vaccination rates.

That’s Ontario’s current plan – while it’s subject to change, the province anticipates lifting mask mandates in March 2022, after other measures like capacity limits and proof-of-vaccination requirements are already gone.

This is more gradual than the approach taken by B.C. and Alberta this summer. When they dropped their mask mandates – alongside a slew of other COVID-19 restrictions – cases went back up. Both provinces have since reimposed masks in most indoor settings.

“I think what happened in Alberta was predictable, but I think all of us really learnt from that experience, unfortunately, with the devastation that we’ve seen in our health-care system,” said Dr. Michelle Bailey, a pediatrician at the Alberta Children’s Hospital.

“Ending mask mandates is an absolutely horrible idea,” said Dr. Barry Pakes, an assistant professor at the University of Toronto’s school of public health.

Dr. Peter Juni, a professor at the University of Toronto and scientific director of the Ontario Science Table, agrees.

“We can’t let go of the masks and we can’t let go of the vaccine certificates,” he told Global News Friday after Ontario announced its plan to ease measures.

“If you want to have a proof of concept of what I just said, go to Denmark. Denmark has a lot of advantages over Ontario, structurally speaking, with a lot less problems with socioeconomic status, a lot less problems with living situations of people. But they lifted nearly all restrictions. And guess what? Case numbers are exploding again. We want to avoid that.”

The U.K., which also lifted masking requirements in July, has seen steadily high numbers of COVID-19 cases since then. Around 68 per cent of the U.K. population is fully vaccinated, according to Our World in Data, compared with about 77 per cent in Canada.

Mask science

Even if case numbers are falling, masks still serve a purpose, said Dr. Susy Hota, an infectious diseases specialist and director of infection prevention and control at Toronto’s University Health Network.

“Masking can be one of the most powerful, and it’s also one of the most easily tolerated interventions we have,” she said.

Several studies have found that masks are an effective way of slowing the spread of COVID-19.

randomized trial from Bangladesh published in September that looked at mask promotion found that even in areas where fewer than half of people regularly wore masks, symptomatic COVID-19 infection was 11 per cent lower than in areas that didn’t have mask-promotion campaigns. Symptomatic infections among seniors were reduced by 35 per cent.

An evidence review published in January also found that masks helped reduce disease spread, and the more people wore them, the better it worked.

Vaccination doesn’t entirely change the game, Hota said.

“The good news is that people are vaccinated. The risk of acquiring the infection is reduced significantly, and their risk of transmitting it off to others is also reduced, but it’s not down to zero,” Hota said. “So that’s why we have to have all of these measures in place and be mindful of when you remove one, making sure you have other measures that can help to mitigate the risk.”

In many provinces, you may remove masks inside a restaurant or while exercising at a gym, but you need to show proof of vaccination to get in, as a way of mitigating risk.

But even as more and more people get vaccinated, Bailey cautions against relying on vaccines alone as the pandemic continues.

“The question that we don’t know is how high a vaccination rate is good enough to be a standalone measure, and I think we really need to have caution going forward that this is really a combination deal,” she said.

Provinces should look at vaccination rates, case numbers, physical distancing measures, and a number of other factors before lifting things like mask mandates, she said.

Wearing a mask in most indoor settings can help to keep case numbers low enough to allow people to take them off where they think it’s important – like at a restaurant with friends, said Dr. Catherine Clase, a professor of medicine and member of McMaster University’s Centre of Excellence in Protective Equipment and Materials.



Written by Leslie Young

A new joint study says that without mask wearing, a two-metre physical distancing guideline may not be enough to prevent the spread of COVID-19 indoors, however, wearing a mask can reduce the contamination range of airborne particles by approximately 67 per cent.

The study, published in the December volume of the journal Building and Environment, was conducted by researchers at McGill University, Universite de Sherbrooke, Texas A&M University, and Northern Illinois University. The research was based on models that examined the flow of liquids and gasses in indoor spaces using a computer program that accurately simulated coughing dynamics.

“Mask mandates and good ventilation are critically important to curb the spread of more contagious strains of COVID-19, especially during the flu season and winter months as more people socialize indoors,” said study author Saad Akhtar in a release.

Coughing is one of the main sources of spread of airborne viruses from symptomatic individuals, and currently, most public health guidelines recommend a distance of two metres for physical distancing between people who are not from the same household to address this.

However, the study found that when people are unmasked, more than 70 per cent of airborne particles pass the two-metre threshold within 30 seconds. By comparison, less than one per cent of particles cross the two-metres mark if masks are worn.

Coughing simulations run by the study found that particles can reach distances as far as five metres away or more if the person is unmasked and depending on ventilation and air conditioning.

Coughing simulation

The effect of mask wearing indoors on the spread of particles over a 30 second interval can be seen here in a coughing simulation run by the joint study. (McGill University/ Building and Environment Journal)

The study found that ventilation, a person’s posture, and mask-wearing impacted the spread of particles significantly, but age and gender had only marginal impacts.

“This study advances the understanding of how infectious particles can spread from a source to its surroundings and can help policymakers and governments make informed decisions about guidelines for masks and distancing in indoor settings,” Akhtar said.


Written by Christy Somos