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Face masks – the million dollar question

Jul 27, 2020 • 14m 56s

Ten key questions on the science of face masks, as experts hunt for consensus.

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Face masks – the million dollar question

173 • Jul 27, 2020

Face masks – the million dollar question

RUBY:

From Schwartz Media, I’m Ruby Jones. This is 7am.

As face masks become compulsory, doctors and public health officials are working to find consensus on their efficacy.

But in the rush to contain coronavirus, there is no time to wait for perfect science.

Today - Amy Coopes answers ten questions about face masks: how they work, and how to use them.


RUBY:

Okay. Amy. First question, how effective are masks in controlling the spread of coronavirus?

AMY:

Well, I think this is the million dollar question, it's the one that everybody wants the answer to. And I think the uncertainty around this question is probably part of the reason why it's taken quite so long for authorities in Australia to kind of get on board.

RUBY:

Amy Coopes is a medical journalist. She wrote about face masks for The Saturday Paper.

AMY:

There's so many studies into this question, you know, the WHO did a big analysis to try and answer this question, and they looked at 172 studies. So there's lots of studies out there. The question is, um, for, you know, public health experts and people who are perhaps critical of this is the quality of the evidence.

So, you know, these are largely observational studies, which means essentially they're not run in a controlled fashion.

And so some of the problems about kind of trying to bring all this evidence together is that mostly the studies are in healthcare settings. They look at surgical masks and respirators as opposed to cloth masks.

And so, um, extrapolating findings from that to the community is very difficult. And we actually don't have any studies, you know, robust big studies, into community mask wearing. And so that's one of the big problems.

RUBY:

So what is the case for wearing masks?

AMY:

So the case for wearing masks, I think, very much comes from what we've seen with the epidemiology of, of coronavirus and how it's being controlled in countries that have done well.

So, many of the experts that I spoke to, in particular, Mary Louise McLaws who works for the WHO and has been involved in their pandemic response, points to the experience of countries who probably are quite much more enculturated than a country like Australia into wearing masks.

Archival Tape -- Mary Louise McLaws:

“All the countries that have SARS, MURS and pandemic flu have responded remarkably fast.”

AMY:

You know, there are countries that mandated mask-wearing very early on in the epidemic. And just looking at the infection rates per million, which she says is a, you know, a good proxy of how countries are doing, Vietnam has been lauded for it’s response and certainly it's got one of the lowest rates of infection in the world, it's like 4 infections per million people.

Archival Tape -- Mary Louise McLaws:

“I mean in Vietnam the masks are not very impressive, they’re usually a single layer. But even a single layer is better than nothing if everyone wears a single layer.”

AMY:

Taiwan is 19 infections per million and they are very big on mask wearing, and always have been in this epidemic. Then you look at somewhere like the US, which is, as we know, not doing so well, they have 12,000 infections per million. Brazil has 10,000 infections per million. So, you know, it's just looking at it from those terms. She says, you know, these are meaningful epidemiological experiments into mask growing having a role.

Archival Tape -- Mary Louise McLaws:

“So I was more skeptical of the evidence but I have become, certainly over the months, seeing the importance of it being a whole package, and the more these papers are coming out the more they’re supporting the idea that ..gosh it doesn’t hurt.”

RUBY:

And what about the case against wearing a facemask? Is there any actual risk that comes from putting one on?

AMY:

So there are risks to wearing masks, particularly cloth masks.

There are concerns around certainly contamination and infection, people not kind of wearing them properly.

Trent Yawood, who's an infectious diseases expert at the University of Queensland, told me there’s been studies that have shown that people do actually touch their face more when they wear a mask as opposed to not wearing a mask, which is some you know, it's uncomfortable. They adjust it.

And certainly, look, I work in a hospital and I wear a mask all day and I touch my face all the time, particularly because I wear glasses. And if it's fogging up your glasses, you need to, you know, adjust the nose and whatever.

The most important risk, though, that has been stressed to me by most of the people I spoke to is this thing called “risk compensation”. So what that means is when people are wearing a mask, they think, “Great, I'm wearing a mask.”

And this may not even be conscious, but they may start easing off on some of the other things that are, in fact, much more important. And they should keep doing, which is, you know, maintaining social distancing, washing their hands and staying at home, particularly when sick.

And certainly Daniel Andrews has alluded to this being a major issue, he said 90 percent of Victorians are not staying home when they’re symptomatic.

RUBY:

So is there a consensus then about whether the benefits outweigh the risks?

AMY:

Consensus? Look, consensus is very hard to come by, I think, you know, in any expert field, probably.

On this one, I would say, given that the advice has changed and given that that's being supported by the experts.

There's obviously a degree of consensus and certainly the WHO finally changed their own advice to be like, you know, in certain circumstances where there's high levels of community transmission and where you're in a situation where it's difficult to maintain distance, then, you know, like masks can be beneficial.

It's a little bit of public health “What about”-ism? But what about if this. But what about what about if it causes this to happen? And I think, you know, we can't allow ourselves not to do something that may be useful because of a ‘what about’ concern. So it's about weighing those risks and those benefits.

RUBY:

Why has the government advice in Australia changed on this? Has the evidence itself changed since the first outbreak?

AMY:

So this is, I guess, something that's vexing people, but it actually is quite a simple explanation. The same guidance that's come from the WHO applies here. It's to do with the context.

So, you know, Brett Sutton has definitely said, you know very clearly that this is the rationale for changing the advice in Melbourne. It's because the situation has changed.

Archival Tape -- Brett Sutton:

“I’ve said before, the second wave, if we are going to call it that, is very different to the first wave that we’ve gone through for a whole bunch of reasons.”

AMY:

I guess what's changed is now we're seeing widespread community transmission.

Archival Tape -- Brett Sutton:

“So we have to reinforce the things that we know will make a difference.”

AMY:

There is still an ongoing debate about the role of aerosol transmission. But the fact that the consensus is growing around, you know, is quite settled around the idea of droplet transmission - sort of underscores that it could be very useful if worn by, you know, sources.

The fact that it is a droplet borne disease that can be impacted too, and not in significant degree by wearing a mask. And the fact that pre-, a-, pauci-symptomatic symptomatic transmission is an issue, and we've got a widespread kind of community transmission, all of those factors, I think, have brought this issue to a head and moved the Victorian government's hand on this question.

RUBY:

We’ll be back after this.

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RUBY:

Amy, my next question on face masks is - does it matter what kind of mask is being worn?

AMY:

Yes, very much so.

I mean, if you look at the evidence, certainly even in the healthcare setting, like these masks have different grades. So like N95, respirator masks are obviously going to offer you the greatest protection.

But that's from very small particles. So there they are reserved for the hospital. But they are, you know, the highest level of protection.

Surgical masks are obviously not quite as stringent, but they offer good protection. We're talking about, like, disposable surgical masks. And that is what, you know, health care workers are wearing when encountering Covid patients in the hospital. So, you know, there’s certainly adequate evidence there.

Cloth masks, there is certainly some evidence out there that has looked at them.

The design of the mask is important. So there should be at least three layers. The outer layer should be hydrophobic. So it should repel kind of, moisture. The middle layer should be a very - like a high thread-count. It should be very snug fitting. You should have at least two, because at the end of every day you should be handwashing with hot, soapy water, one of your masks.

And you know, when it's not being used, if it's dirty it should be in a Ziploc bag until you can wash it. And just doing hand hygiene like never before. Anytime you touch the mask or your face, you should be doing hand hygiene.

And, you know, this is the key message really that's come from this story, is that we must keep doing all the things that we probably are very sick of doing, you know, and that's part of the concern around the risk compensation idea - that people have fatigue, they have fatigue around lockdown. But this disease is not going anywhere, and so we need to have buy-in from the public.

RUBY:

And do masks protect the wearer from infection? Or do they stop the wearer spreading the virus?

AMY:

Yeah, so I guess we’ve talked about this but essentially the evidence for masks and the rationale for them being rolled out in Melbourne is that it's a form of source control.

So it's actually to stop the person who's wearing it from spreading the virus.

You know, one in five infections may be coming from asymptomatic people. So it's - it's a form of source control.

It's actually... The evidence is not there for them being protective, it's to stop you from spreading your droplets from your mouth to other people and the environment.

RUBY:

Mm hm. Would other coverings, like neck warmers or scarves, also limit transmission?

AMY:

In theory, yes. That's, of course, a possibility.

It's whether it's going to be more dangerous to the person who's wearing it, I suppose is, is the question. Wearing a neck warmer or a scarf around your face is obviously going to certainly limit droplets, leaving your mouth and spreading into the environment.

It's really just not going to do it quite as effectively as a mask.

RUBY:

Mmhmm. If people get dizzy wearing masks or have other kinds of side effects, are there different types that they could wear instead?

AMY:

Yeah, that's interesting. This is one of the risks that was highlighted to me by Julie Leask, who’s a risk communication specialist which is that, you know, they are uncomfortable and some people can kind of get dermatitis or stuff on their face from them.

Archival Tape -- Julie Leask:

“I say this as a former registered nurse who worked in operating theaters and wore them all day. That they are uncomfortable, they are stifling..”

AMY:

I guess: try different things. You could certainly try a different kind of mask if you're wearing a surgical mask and you're finding that's kind of making you feel claustrophobic. You could try a cloth mask, which can be a bit, like, lighter on the face. Make sure it's an appropriate design, of course.

Archival Tape -- Julie Leask:

“You need to be trained to use them properly. You can contaminate yourself if you touch the mask and don't wash your hands afterwards. So there are certain ways you should wear them.”

AMY:

I would not recommend anybody wearing an N95 mask or try to get one because they're very constrictive and they do actually make you feel like you can't breathe very well and they're not going to protect you from coronavirus.

But the best advice, I suppose, in the scenario where you're finding a mask intolerable and certainly all the experts would emphasize this, is stay at home.

RUBY:

Okay. And last question. On balance here, would the best thing to do be to follow the advice to wear a facemask?

AMY:

If I lived in Melbourne, would I wear a mask? Absolutely. Do most people I know who live in Melbourne wearing a mask? Absolutely. Most of them are doctors.

And I think that, you know, playing a part, doing something, taking affirmative action and signaling to other people that you care about them: those things aren't to be underestimated.

Archival Tape -- Julie Leask:

“I think I should just cut to the damn chase and say that essentially what we're doing is we're settling for lower quality evidence because of the situation we're in. We've got a strong desire to control this before it really catches fire. You know we are at this pivotal point right now where we really want to control this.”

RUBY:

Amy, thank you so much for talking to me today.

AMY:

No worries.

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RUBY:

Also in the news -

Victoria recorded 459 new cases of coronavirus yesterday. Ten people in the state died from the virus over the weekend.

And Black Lives Matter rally organisers in Sydney are intending to file an appeal against a Supreme court decision to prohibit a rally going ahead on Tuesday.

NSW Police took the organisers to court over concerns the event would breach public health orders.

The organisers have said the March will go ahead regardless.. with more than 4,000 people indicating that they’ll attend.

**

I’m Ruby Jones, this is 7am, see you tomorrow.

As face masks become compulsory, doctors and public health officials are working to find consensus on their efficacy. But in the rush to contain coronavirus, there is no time to wait for perfect science.

Guest: Health journalist Amy Coopes.

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7am is a daily show from The Monthly and The Saturday Paper. It’s produced by Ruby Schwartz, Atticus Bastow, and Michelle Macklem.

Elle Marsh is our features and field producer, in a position supported by the Judith Neilson Institute for Journalism and Ideas.

Brian Campeau mixes the show. Our editor is Osman Faruqi. Erik Jensen is our editor-in-chief.
Our theme music is by Ned Beckley and Josh Hogan of Envelope Audio.

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173: Face masks – the million dollar question