We now have the chance to use our new mask-prowess to curb the spread of TB as well — but only if we consider keeping masks woven into the fabric of our lives after the COVID pandemic has passed.


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Sister Pelisa Dlomo is sitting outside a small clinic on a crisp winter morning in the rural Eastern Cape. The queue of patients for the day is accumulating, rapidly filling the facility’s narrow passages. 

Some patients are asked to put on masks as staff look over their test results. For many this will be the moment when they realise they have tuberculosis (TB).  “They say the masks stigmatise them. It’s making everyone know that that one is having TB,” Sister Dlomo explains with a sigh. “My patients feel like they’re depersonalised in some way by wearing masks, that it’s a signal for people to run away from them.”

How TB can benefit from measures taken to contain COVID-19

I am a medical doctor and for the past 8 years, I have been studying ways to prevent TB from spreading, interviewing health workers and patients. 

Being diagnosed with TB means wearing a mask until a patient has taken medication for long enough to not be infectious any more. The masks prevent people with TB from expelling the germs that cause the disease into the air.

TB — a curable illness — is the leading infectious disease killer globally and South Africa has one of the highest case loads of this condition. In 2019, it killed 64 000 people in the country. 

But until recently, mask-wearing led to TB patients facing severe stigma — because patients with other diseases were mostly not required to wear masks too.  

This type of stigma has severe consequences. 

Research has found that the fear of TB-related stigma makes people less likely to undergo TB screening or to take up treatment, which in turn leads to the spread of the disease.  

This year’s COVID-19 epidemic, however, dramatically changed the acceptability of one of TB’s most valuable prevention tools. In South Africa, masks have become part of our normal life, embraced as an important method to prevent the spread of COVID-19.  

As a result, the social meaning of masks has transformed from being a symbol of illness, to becoming a sign of solidarity amidst a common threat.   

And although COVID-19 has had a destructive impact on TB services and testing — TB testing with GeneXpert machines in South Africa declined by 48% per week between February and May because of restricted movement during level 5 lockdown — the country now has the chance to use our new mask-prowess to curb the spread of TB as well. 

But only if we consider keeping masks woven into the fabric of our lives for a while longer — even after the COVID pandemic has passed.

Why should we care about TB now, when it has been part of our lives for many years?

COVID-19 is only the latest threat to enter the air we all breathe. In South Africa, crowded spaces such as public transport, schools, hospitals and mines have long posed a threat to our health.

In 2019, TB killed far more people in South Africa than what COVID-19 is likely to do in 2020. Eight months since the start of the outbreak in the country, COVID-19 has led to about 19 000 deaths — that’s less than a third of the 64 000 people who died of TB in 2019.  

There is a misperception that TB only affects people with weakened immune systems (as may result from HIV or malnutrition), but the reality is that the TB bacterium spreads through the air and that everyone is at risk. 

We have been slow in recognising the disease’s impact, because TB progresses slowly. 

A patient with COVID-19 can develop symptoms days after being in contact with an infectious person; with TB the onset of symptoms can take months or years. After coming into contact with TB, some patients can initially contain the infection, leading to a latent TB infection with no symptoms. Whether a patient develops symptoms immediately or in years depends on how much TB they are exposed to, their immune system, time and luck. 

This slow timeline poses a challenge for prevention, but just because the disease presents slowly, does not mean we should be slow in our response.

Masks for patients with TB have been recommended to prevent the spread of the disease for several years. This is known as source control. In practice, this means that if someone who has TB, but who is not yet on treatment, wears a mask, this can reduce the spread of multidrug resistant TB — for which treatment is more expensive and the death rate higher than for ordinary TB — by up to 56%, according to 2012 research published in the American Journal of Respiratory Care and Critical Medicine. 

But because of social norms and stigma, such as those faced by the patients of Sister Dlomo, the use of masks to prevent the spread of TB has been limited to health facilities and by sick people. Public spaces, such as poorly ventilated offices and taxi’s can be hotspots for the spread of TB, but before the COVID-19 pandemic, wearing a mask would cause quite a consternation in such spaces. 

Just as with COVID-19, knowing who has TB and poses the most risk of infecting other people is difficult. The old belief was that masks are helpful only for symptomatic TB patients, those who are coughing, as they are likely spreading illness. However, recent research suggests that half of people with TB may have no symptoms at all.  This suggests that for every person asked to wear a mask to prevent the spread of TB, another person is spreading TB without showing symptoms or feeling ill at all. 

This is why the widespread mask wearing by the public that started with the COVID-19 pandemic offers such promise for TB. By establishing social norms and identifying places where wearing a mask will offer communal protection, we may be preventing TB as well as other diseases.

Why we should carry on wearing masks beyond COVID-19

But despite the possibility of communal protection, wearing a mask is not convenient. 

Masks have also come to symbolise the COVID-19 pandemic and this poses a challenge. In the near future, it may become tempting to discard our masks as we yearn for a post-pandemic life. 

But if we throw away our masks after COVID-19, we would also be throwing away an opportunity to make a difference to the suffering caused by TB. 

Masks are an integral part of the anti-TB toolkit, although we should also look at implementing low cost adaptations to improve natural ventilation, using air disinfection like germicidal UV and auditing the safety of shared air using CO2 levels, which will all help to keep COVID-19 at bay as well.

We have already made great progress with the most difficult step — achieving widespread access to reusable cloth masks. It is now part of our routines to grab our mask when leaving the house. We’ve even figured out the details of ear elastics, ties around the head, nose clips for glasses and patterns for different outfits. 

But our mask guidelines for our post COVID-19 lives can be smarter. 

Instead of blanket rules, as we used at the start of the pandemic for COVID-19, we should identify high risk spaces where TB commonly spreads and strongly encourage the use of masks in those spaces as much as possible. 

This is important for areas with poor ventilation such as taxis, healthcare facilities, schools and shopping centres and should become part of broader airborne disease prevention, rather than a COVID-19 specific measure. 

With the wider acceptance of mask-wearing, managing the spread of TB at Sister Dlomo’s clinic is starting to look very different. 

Instead of selecting a couple of people to brandish the mask label, everyone at the facility is now wearing their own cloth masks, as required by government regulations, protecting each other not only against COVID-19, but also against TB, flu and any unknown future airborne diseases. 

If they stop doing this after COVID-19 has passed, we would have missed a crucial chance to apply the lessons learned from this pandemic to curb TB and destigmatise preventive tools. 

“I think treating people with TB equally with respect and supporting them is so important,” says Sister Dlomo.

She turns a page in her patient register book, opens a new box of masks, and explains: “If we can just fight that stigma and stand together.”

Helene-Mari van der Westhuizen is a South African medical doctor and doctoral researcher in the Nuffield department of primary care health sciences at Oxford University, studying TB infection control in rural settings in South Africa. Koot Kotze also contributed to this article.