Switch to N95 masks with surge in COVID-19 Omicron cases, infection control expert says

With the emergence of the seemingly more transmissible COVID-19 Omicron variant, an Ontario infection control epidemiologist says using N95 masks in public settings versus other types of masks is becoming critical for personal protection.

Colin Furness, who is also an assistant professor at the University of Toronto, said when masks were first introduced at the beginning of the pandemic there was a strong social obligation as well as a need to protect others from droplets and “to some extent” block aerosols.

However, when asked about still using cloth and surgical masks, he said Ontario is at “a different place” currently.

“For starters, we understand that airborne transmission is not a possibility but a major way in which COVID spreads – particularly with variants that are more contagious,” he said.

RELATED: COVID-19 Omicron cases in Ontario estimated to double every 3 days, science table reports

“If you’re vaccinated, you’re not wearing a mask to protect other people from your droplets — you’re wearing a mask to protect yourself from other people’s aerosols.”

Furness said when it comes to choosing N95 masks, he noted there are a variety of options on the market including CN95 and KN95. He said the masks are basically manufactured to a standard where you breathe and 95 per cent of small particles are filtered out.

“That is safe, that is enormously safe, you’re breathing through that fabric and it’s blocking things out – it’s blocking out virus,” Furness said, adding the availability today of such masks is much higher compared to the beginning of the pandemic.

“There’s a number of different varietals, but they all do the same thing: they sit on your face without gaping or at least they’re supposed to if you put them on properly … That’s the safe way to be when you’re sharing air with others in public.”

He said when it comes to the blue disposable surgical masks, those offer good protection but with the sides tending to leave openings the masks lose effectiveness.

RELATED: Ontario LTC visitors must be fully vaccinated, mandatory testing for staff

However, Furness said he’s heard from some who work in frontline capacities that they have been mandated to wear those types of masks since premium N95 respirators need to be fit-tested — something he said is more applicable to a high-risk hospital setting.

“The logic doesn’t make sense because blue masks have great big gaps around them and an N95 mask that may not fit perfectly is still bound to fit as well or better,” he added.

While Furness said he hasn’t tried it and couldn’t endorse it, he said mask braces have come to the market to help create a tighter seal on those types of masks — calling the addition of that “a pretty smart strategy.”

As for cloth masks made at home or bought at stores, he said it’s important that there be three layers — two cloth ones and a layer of polypropylene — in order to help protect against droplet transmission. However, he added many are not so good at protecting from aerosols.

Regardless of the mask, Furness said there’s a simple guideline to follow when it comes to choosing the right face covering.

“Find one that fits well that when you put it on the mask physically moves in and out when you breathe and then you know it’s forming a decent seal,” he said.

Meanwhile, Ontario continues to see rapid growth of cases linked to the Omicron variant. During an update at Queen’s Park Tuesday afternoon, Ontario Chief Medical Officer of Health Dr. Kieran Moore said it’s estimated the variant is more transmissible than the Delta variant and that it infects four to eight times more people by comparison. However, he added work is still being done to understand the variant and its severity.

Moore also announced new measures at the province’s long-term care and retirement homes such as restricting general visits to those who are fully vaccinated.

Furness echoed concerns raised by Moore when it comes to the Omicron variant.

“It doesn’t need to produce more severe illness to crash our health care system. It’s a numbers game. If we get a million infected people all at the same time, we’ll be unable to provide hospital beds for people who need it and when that happens mortality goes up,” he said.

“It’s going to come very fast. Its doubling time is very fast. So it’s here, it’s already doubling, and in the next two or three weeks it’s going to be something I think that we haven’t really seen before or imagined before and then it’s going to go away almost as quickly … part of it’s going will be an acceleration of third doses, part of it will be people choosing to wear N95 masks and part of it will be closing some things down to reduce weeks.”

Yesterday I told my barber that she must switch to N95 masks immediately. She listened, & she's smart.

But she said she *can't*: if a public health inspector shows up & she's not wearing the prescribed, lousy, gaping blue procedure mask, she could be shut down.

So we're hooped.

— Colin Furness MISt PhD MPH (@FurnessColin) December 13, 2021

h/t to @graemeblake who has pointed to the availability of "mask braces" that fit over a blue surgical mask and are effective at closing gaps.

This strikes me as a promising choice for teachers and others who are being prevented from wearing adequate PPE.

— Colin Furness MISt PhD MPH (@FurnessColin) December 13, 2021

Thank you, @TOPublicHealth for this new vaccination capacity.

It is urgent, I mean really urgent, that everybody who can get a third shot, do so immediately.

Please.

Two shots means you are now functionally unvaccinated. The third shot is the protection. https://t.co/jSgziAMZNG

— Colin Furness MISt PhD MPH (@FurnessColin) December 13, 2021