HomeArticles‘Everyone should wear a cloth mask.’ But do they work?

‘Everyone should wear a cloth mask.’ But do they work?

Guidelines around the world are changing to recommend the use of masks. But you still shouldn’t be buying medical masks – rather make your own at home.

Wear a cloth face mask in public. That’s the national health department’s new recommendation as from April 10. 

Before this, we were told to absolutely not wear face masks to prevent ourselves from contracting the new coronavirus, known as SARS-CoV-2 — unless we were taking care of an infected person.

So why the about-face? 

Well, in some ways the argument is still the same: masks won’t protect the person wearing one against getting infected with the virus, the department says. But now that SARS-CoV-2 has started to spread locally — as opposed to mainly being imported by people who arrived in South Africa from high-risk countries — there is an increasing risk that you could be infected without knowing it and, as a result, spread the virus to others when you cough or talk. 

A mask, research in the journal Nature has shown, makes people less likely to release droplets of spit carrying the virus into the air that can infect others.  

In short, the new recommendation to wear masks is a sort of a last resort. Because we live in a country where many people aren’t able to practice social distancing or wash their hands — the two main ways to prevent the spread of the virus — masks can add another layer of protection.   

The health department doesn’t want us to wear surgical masks (the ones you can buy in chemists), as health workers need them and there’s a global shortage. 

Rather, you should make a cloth one, which you can wash after each use.

But do cloth masks work?

Research on medical mask use in communities is inconclusive. When it comes to cloth masks, there is even less evidence to show whether they work or not.

With the research so unclear, it comes down to individual countries around the world to decide what’s best for them.

On the health department’s coronavirus website, it says:

“Cloth masks are easy and not expensive to make, reusable and help reduce the transmission of COVID-19 by acting like a shield to contain the respiratory droplets through which the virus spreads.”

Here’s what the science can tell us:

Earlier this month, the Nature study found surgical masks helped stop people with symptoms from spreading influenza and other coronaviruses similar to SARS-Cov-2. But the research did not look at fabric masks.

The first randomised trial studying cloth mask use (by healthcare workers) was published in the BMJ Open in 2015. The study, set in Vietnam, cautioned against the use of these masks because they led to more infections than in those wearing medical masks.

Fabric masks were more likely to stay wet and hold moisture, plus they didn’t filter out as many infectious particles as medical masks and were reused — this, the study’s researchers argued, all led to increased infections.

But, a 2008 study published in PLoS One, compared cloth masks to surgical masks as well as respirators, or special masks worn by healthcare workers that can filter very small particles. The research found that all three types of masks offered varying degrees of protection to the wearers in human volunteers. In laboratory simulations, the study also showed all three conferred a slightly lesser degree of protection to those around the wearer.

In 2013, research in Disaster Medicine and Public Health Preparedness compared the effectiveness of homemade cloth masks to surgical masks to protect people from the flu. The study found that both masks worked to reduce the spread of particles exhaled by wearers. But surgical masks were three times better at protecting the wearer from the flu virus than self-made fabric masks and scientists recommended that “a homemade mask should only be considered as a last resort”. 

A mask, research in the journal Nature has shown, makes people less likely to release droplets of spit carrying the virus into the air that can infect others. (Kelly Sikkema, Unsplash)

So why should cloth masks be considered at all?

Kerin Begg is a public health specialist at Stellenbosch University and helped draft the Colleges of Medicines in South Africa guidance on the use of cloth face masks that informed the Western Cape health department’s policy.

The Colleges of Medicines in South Africa is an oversight body that sets the standard for medical specialisations in the country.

After reviewing the existing research, the Colleges found the evidence too uncertain to make a clearcut recommendation for community use of cloth masks nationally. In spite of this, on 2 April the Western Cape decided to recommend that everyone, including those who were not ill, start wearing masks.

“The best time to use face masks would be a bit later [in the outbreak] when the prevalence rates are much higher,” Begg says.

She believes it would have been wiser to only have recommended fabric masks once there was widespread community transmission of the virus, with around 10 000 cases, because then there would be more risk to the general public of getting infected by close contacts.

On Tuesday night, South Africa had a total of 2 415 confirmed COVID-19 cases — less than a quarter of 10 000. 

Why then, the push for cloth masks? 

“I think people want some sort of visual sign,” explains Begg, who herself has been hounded by people wanting a conclusive recommendation that they should wear masks.

“It helps people feel better, it reduces anxiety. But I think it may create a false sense of security and that was part of our concern.”

Once people wear masks all the time, says Begg, they might drop other preventative steps, such as handwashing. There is also a good chance that people will wear the masks incorrectly and render them pointless. She says incorrect usage can range anywhere from people who touch their face more to adjust the mask to people who put the mask under their chin when it gets uncomfortable.

To Begg, the thought process from a policy standpoint is: “If that’s [cloth masks] the only thing that can help us, then maybe we just kind of try it anyway.”

Why does South Africa need cloth masks? 

The most basic steps people should be taking — washing hands, maintaining distance from others and good hygiene — are not things that can be easily carried out by most South Africans.

Almost half the population doesn’t have access to water in their own homes, show 2018 Statistics South Africa data — and high levels of inequality in the country means that those living in poorer communities will be disproportionately affected by the outbreak.

These are people that might not be able to practice social distancing or wash their hands regularly.

Although the government has delivered over 6 000 water tanks to those who need them, people living in these communities need a variety of options for how to protect themselves.

The solution: Add cloth masks as another option.

“If we were living in a perfect world where we had really great social isolation and physical distancing and we didn’t need to use public transport and all of that, I might also go for a higher standard of evidence,” says Max Price, former vice-chancellor at the University of Cape Town and part of the ministerial advisory committee on COVID-19.

“But given that we don’t have that and that people are close together, we should just use whatever we have.”

For Price, the debate is not about whether or not cloth masks work, but rather whether the general public should wear masks to reduce infection. The answer to which he believes is a resounding yes.

“The fact that we don’t have evidence that it works, doesn’t mean that we have evidence that it doesn’t work,” Price reasons. “If laboratory evidence suggests that it could work, then we should just use everything we can.”

The impact that general use of medical masks would have on the healthcare sector has already been noted, but there is another drawback that has perhaps been overlooked.

The reality is that even if there were enough medical masks for health workers, recommending their use to the public would still disadvantage some people. If you’re telling people to wear masks, you need to be sure that everyone has access to one — and this, likely, wouldn’t have been possible. 

But that’s the beauty of homemade masks, says Price.

Currently, there is no standard and everyone can make one depending on what they have access to at home.

[WATCH] The department of health shows you one way to make a mask at home

The only guidelines set out by the national health department are:

  • Your mouth and nose should be covered completely;
  • Wash your mask with warm soapy water and iron when dry;
  • Change your mask when it is wet or visibly dirty;
  • Everyone should have at least two masks, so one can be worn while the other is being washed.

Additionally, the department says you should not lower or remove your mask when talking, coughing or sneezing. Do not touch your mask when it is on your face and never touch the inside of the mask. Wash your hands before putting the mask on and after removing it.

“It’s important not to set the bar so high that people can’t meet it,” Price explains. The message should be: Use anything that you can to catch droplets and also to prevent yourself from breathing in droplets.

“The thicker the better, the tighter the fit the better and there are some designs that may be better than others, but use what works for you. And if what you’ve got is a scarf or a towel to cut up or a bandana, then that’s good.”

Previously, the government’s recommendation was that only people who have symptoms of COVID-19 should wear a mask, but new evidence has shown that people might be able to transmit the virus even though they show no symptoms of the disease.

According to the World Health Organisation’s head of emerging diseases Maria Van Kerkhove, the team that collected data on China’s COVID-19 outbreak found that 75% of people developed symptoms after being classed as asymptomatic. A recent study by the US Centers for Disease Control and Prevention showed similar results at a nursing home where almost half of the 23 positive patients didn’t have symptoms at the time of testing.

Price concludes: “Now that we take the view that most people are infectious without knowing it and they can’t quarantine, we need to find some other method of adding to the physical isolation or physical distancing and masks can be the way of doing that.”

Aisha Abdool Karim was a senior health reporter at Bhekisisa from 2020 to 2022.