Saskatchewan·Q & A

Is it better to wear a double mask or an N95? Infectious diseases specialist answers questions on COVID-19

Dr. Alex Wong answers questions about Omicron.

Omicron brings different challenges, here's how to deal with them

Dr. Alex Wong is an infectious disease doctor at Regina General Hospital. (Submitted by Dr. Alex Wong)

The new COVID-19 variant Omicron has been a game changer in terms of how health-care professionals handle the pandemic. Omicron has spread quickly, leaving many people unsure about how to keep themselves and others safe.   

Regina infectious diseases specialist Dr. Alex Wong took some time to speak to The Morning Edition host Stefani Langenegger and answer listener questions.

Is it better to wear a double mask or an N95? And if the N95 is better, why is that not a recommendation from the Saskatchewan Health Authority?

The SHA actually just recently changed guidelines, and are now recommending N95s, in the context of acknowledging that airborne transmission of COVID-19 is actually very real and relevant. In the last couple of weeks, N95s are now recommended for all health-care workers, who are interacting with any COVID positive patients, regardless of the type of interaction.

The bottom line here is that respirators, like N95s or KN95s, or KF94s are better than medical and surgical masks and cloth masks because they filter a lot of what is in the air and what we breathe much, much better, (filtering) 95 per cent plus, compared to medical masks, which are probably between 50 to 70 per cent, and cloth masks, which are even less. 

If you have the financial means to do so, upgrading to a respirator for all indoor public interactions is recommended. If you can't afford or can't find a respirator mask, then you need to certainly upgrade your cloth mask, at least to some type of a medical or surgical grade mask to improve the amount that's filtered. Double mask by placing a cloth mask over top of a medical or surgical mask to try to make that fit much tighter and to reduce the amount of leakage. 

Especially with Omicron being as contagious and transmissible as it is, we really want to do the best that we can to upgrade masks as best as possible, both for yourself, as well as for all your family members, including your kids. 

LISTEN | Dr. Alex Wong on symptoms, testing and safety:

What is the best way to use rapid tests?

The best way to use rapid tests, at this point, is when you're asymptomatic and you want a way to screen yourself to ensure that you're not actually positive. For example, you could use them before you head to work, or kids could use them before going to school as an extra layer of safety. 

The challenge and the confusing thing for a lot of people becomes once you're symptomatic. The challenge with rapid tests is that they're not completely reliable in terms of picking up the virus. So when you're symptomatic and your risk of being infected with COVID is high, and the test result is negative, that's not good enough to say: "I don't actually have COVID," because of the nature of how the test works. In that type of a situation, up until recently, the suggestion was to get a PCR test. And that's still the case if you're symptomatic.

But if you have a positive rapid test, you can rely on it, because the so-called specificity of the test is very high. So if you see those two bars, that is essentially a guarantee that you do have COVID and that you do need to isolate. 

The other question a lot of people have is: 'Should I just be swabbing the nose, which is kind of what you know, the box instructions would say, or should I potentially swab both my throat as well as my nose?' There is some data that would suggest that doing a combined throat and nose, or nasal swab, at the same time might increase yield because the amount of virus in sort of the back of the throat and then the sort of upper respiratory tract is higher or gets faster, higher than the amount of virus in the nose. 

If you're going to try to swab your throat and your nose, don't eat or drink 30 minutes beforehand, to optimize the yield of the amount of virus that you have in the back of your throat. But again, regardless of the results, whether it's negative or positive, that's not a reason for you to go out and about if you're symptomatic. 

The bottom line right now is that if you're symptomatic, you must isolate yourself. If you want to get out at five days, you have to be asymptomatic at day three and then have no symptoms for two straight days in order to exit isolation. If you have symptoms, you cannot go; you are still very much potentially infectious.

We've learned about the airborne nature of this virus versus large droplets. What's your recommendation in terms of working in an open area with other people, where you're spaced out more than two meters, but allowed to take off your masks at your desks?

When people are smoking in an indoor setting, it's poorly ventilated, and you could smell the smoke, you know, like for an hour or two or something like that, that's the same way that you can sort of think about COVID. If you can breathe that smoke in and smell it, then you can breathe the virus in and potentially become infected too.

That's why ventilation is so important. If you upgrade the ventilation and get all that air moving out quickly, that's going to significantly reduce risk. If you're pretty much sitting, distance is not good enough to imply that you're safe. I would wear a mask, personally, if that was me.

ICU numbers are at their lowest point in more than six months, despite the surge in Omicron cases. Isn't it fair to say that this strain is less dangerous than Delta?

We've heard a lot about how when you compare one to one, somebody that's infected with Omicron is less likely to become severely ill compared with someone that has been infected with Delta. And that is the case as the Omicron reproduces less rapidly in the lungs and generally causes less severe lung disease compared with the previous variants like Alpha and Delta, which would sometimes just completely ravage someone's lungs. Even someone otherwise completely young and healthy could need life support, or might have ended up on a ventilator for weeks at a time. We're not quite seeing that pattern now. 

The challenge with Omicron right now is that there's a typical lag between the number of cases and subsequent ICU and hospitalizations. We're seeing that across the entire world, including in Ontario and Quebec, where the numbers of people in hospital and ICU continues to rise very quickly, even though the nature of the illness is a bit different.

The problem is that when so many people get infected, even if a small proportion of those people become severely ill, that's going to be significant enough to significantly strain our healthcare system. We significantly expect to see the numbers of hospitalizations and ICU admissions climb in the coming weeks. And that's when we're going to face some real challenges in our health-care system.

What happened to Delta? Did Omicron push it out? How did it do that? And can it come back when Omicron subsides? Or is the virus weakening as it mutates?

It's very, very unlikely that Delta will re-emerge because Omicron has certain survivability and reproducibility advantages. The main one is that it's much more transmissible. And the reason for that is probably twofold. One is that it replicates much more quickly in the upper respiratory tract, which makes you infectious much more quickly. The second reason is because of all of these mutations on the so-called spike protein, which does a much better job of evading protection from either recovery from natural infection or from vaccine. The protection that our bodies have against Omicron isn't as good as it was with previous periods.

We can almost think of Omicron as like a whole new virus compared to all of the other variants that we've had in the past. So for those reasons, it's just spreading so fast, so quickly, vaccines and natural covering or some combination of the two are not completely protective, obviously, against getting infected. There will be some other variant probably at some point in time, hopefully not in the near future that will do something similar to Omicron. And we'll have to see what it does at a clinical level as well.

For those who got Delta or some previous version of COVID, how resistant are they now to getting Omicron? 

There are some significant mutations and changes with this so-called spike protein with Omicron. The data suggests that recovery from natural infection with Delta, for example, only provides very limited protection against getting infected with Omicron. That number could be as low as 15 per cent or 20 per cent. So it's nowhere near as good as what we believe to be the case with previous variants where they're relatively minor changes in terms of the mutations in spike protein. From the immune system perspective, Omicron is almost like a whole new virus and what we have in terms of our immune memory, doesn't do super well, in terms of protecting us against that.

Dr. Wong, we also had a lot of questions about whether one should get a confirmatory PCR test if they test positive on a rapid test. Would you go get it confirmed if you had a positive rapid test? And how should you record a positive rapid test? 

Right now, I think that the government's public health guideline has been just to remain isolated. If you're significantly symptomatic, I do believe the guidance is still that you should try and go to access a PCR test if you can, in order to make the diagnosis.

A lot of people are asking how do I document a rapid test? There is no official way to report a rapid test, as far as I know, right now in the province. If you can do a rapid test on yourself, or have somebody do a rapid test on you and film it with your cellphone from start to finish to document that entire process, and then speak with your family doctor, in order to get that onto the chart relatively quickly.

Keep that video as a way to document: 'Yes, indeed, I actually did have COVID.' I think that video would be something that could potentially be valid. It's hard to really know at this point in time, what's going to happen with all of that going forward. 

What do we do in terms of boosters or those who had three or even four shots because of mixing and matching?

Guidelines are changing so fast, it's hard to generalize for everyone. What I would just strongly suggest is everyone go and get as many doses as you're actually eligible for. We know with Omicron, that the third or fourth dose, makes a tremendous difference in terms of protecting you against symptomatic infection, although two doses does seem to continue to provide meaningful benefit against hospitalization and severe illness.

When can we expect roll out of booster shots for teenagers and vaccines for kids under the age of five? 

We would expect boosters for those 12 years and older in the relatively near future. They've already been approved in the United States. And I know that regulatory processes are working their way through Canada.

Unfortunately, the news for young kids under five isn't as good. Both Pfizer's and Moderna's trials, are delayed for various reasons. Pfizer's trial doesn't seem like they use a dose high enough. So they had to give a third dose that delayed everything. Moderna has asked for more patients to be enrolled. So we're not probably looking until maybe April, May or even longer at this point, which is disappointing for a lot of people with young kids. But that's another reason to do what we can to protect them. 

Thank you, Dr. Wong for your time this morning. We really appreciate it.

Thanks, Stef. Always a pleasure.

Written by Florence Hwang, with files from The Morning Edition. Q&A edited for length and clarity.

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