By Karen Taylor, Director, Centre for Health Solutions
Since the outset of the COVID-19 pandemic debate has been growing about the benefits or otherwise of the general public wearing face masks to help control the spread of the virus. While arguments exist on both sides of the debate, history and culture has played a crucial role in polarising opinions. Nevertheless, all countries have accepted the need for mitigation strategies and importantly, the views of public health advisors and most governments have now converged in favour of wearing masks. While growing numbers of people across the world have begun to wear face masks in public, confusion still remains as to the merits or otherwise of wearing a mask. This week’s blog discusses of the supporting evidence for face masks and, why they have become the new ‘must have’ accessory.
How has the wearing of face masks evolved across the world?
For many years, Western society has been bemused to see increasing number of visitors from Asian countries, such as China, Taiwan and Hong Kong, wearing face masks in public. In these countries the culture of wearing face coverings in public has evolved due to increasing levels of pollution and, importantly, previous experience with the SARS and H1N1 virus outbreaks. The advent of the COVID-19 pandemic has normalised these behaviours.
In early March 2020, Venezuela and Vietnam were among the first countries to impose the mandatory use of face masks in public. In April, the Czech Republic became the first European country to make wearing masks mandatory in supermarkets, pharmacies, and on public transport; closely followed by Germany who made the wearing of face masks compulsory while on public transport and shopping. By May, France, Spain, Portugal and Italy had made the use of face masks in public mandatory, as these countries prepared to emerge from lockdowns.1 By mid-June, more than 120 countries had made wearing masks in public places compulsory (Figure 1). The UK and US were particularly conspicuous in having a low percentage of people wearing of face masks.2
Figure 1. Mask use around the world. Percentage of people who say they always wear a mask going out (19 June)
Source: IHME, University of Washington3
While, the tradition and culture of the country will impact adherence, opinions can change rapidly, for example in Italy uptake went from about 20 per cent up to 84 per cent over three weeks, and quickly rose to 99 per cent.4 Figure 2 illustrates how behaviours in various countries have evolved over time and Figure 3, provides a snap shot of individual behaviours.
Figure 2. YouGov COVID-19 behaviour changes tracker: Wearing a face mask when in public
Figure 3. How often have you worn a face mask outside your home to protect yourself or others from coronavirus (COVID-19)?
Details: Europe; YouGov; Imperial College London; June 22 to June 28, 2020; Approx 1,000; Online survey
Of course, wearing face masks is only one part of the mitigation strategies seen across countries to contain the spread of the virus; social distancing, hand and environmental hygiene measures are still important as restrictions continue to be lifted. Importantly, while the timing of and the terms and conditions attached to, easing restrictions have varied from country to country, those countries that locked down early and embraced the wearing of masks appear to have better outcomes.
What is the UK’s position on face masks in the UK?
UK nations have devolved powers which has meant that England, Scotland, Northern Ireland and Wales have made their own decisions on coronavirus lockdown strategies, including the wearing of face coverings including masks (see Figure 4).7 Under the new rules, people who do not wear a face covering will face a fine of up to £100, unless they qualify for an exemption (children under 11, certain disabilities and breathing difficulties).8 The different interpretations across the UK have added to public confusion and concern over the merits or otherwise of wearing face-coverings.
Figure 4. UK’s position on face masks and coverings
So what is the latest advice on wearing face masks?
Historically, Western society has never had a culture of using masks among the general public. Moreover, the initial position of several influential institutions was that masks were not recommended as necessary for the general public. One reason was a valid concern that the mass use of masks would deplete the resources available for healthcare workers, especially due to shortages at the height of the outbreak. Furthermore widespread use of disposable masks would be expensive to provide to billions of people, not to mention the environmental impact.
Furthermore, there are no randomised control trials on the efficacy of universal mask use in stemming COVID-19 transmission. Partly as such a trial would require complete adherence for it to be valid, and the poor adherence has been seen in public gatherings where masks are optional, especially when alcohol is ingested (many countries including Thailand actually banned the sale of alcohol during their lockdown). Nevertheless, the cumulative multifaceted evidence on mask efficacy, gathered as part of ‘The Delve’ masks report, provides strong support for their use:
- Longitudinal data support initial findings that the majority of SARS-CoV-2 infected individuals remain asymptomatic during and post infection. New evidence suggests that transmission of SARS-CoV-2 by asymptomatic individuals is a substantial driver, including through droplets, aerosols and super spreader events.
- Evidence, based on observational and modelling data in humans, shows that masks, including cloth masks, prevent onward transmission of infection in intercepting droplets and aerosols protecting the wearer and others.
- New evidence finds that the use of clear plastic face shields can prevent onward transmission of droplets and aerosols; addressing the concerns from individuals, such as individuals with hearing impairments or breathing disorders that cannot use masks.
- Mandatory use of masks or shields in all situations outside the home where physical distancing is not possible will help to counterbalance the expected increase in population-level exposure as lockdown ends.9
For the past month or so the British Medical Association and the World Health Organization have recommended the use of masks in public settings.10 Moreover, the updated DELVE report presents new evidence that further supports the universal use of face coverings in all settings where distancing is not possible or predictable. Universal mask use, is seen as a cost-effective method facilitate the opening up of society. The cumulative evidence strongly supports the use of masks in all circumstances particularly where physical distancing of more than one metre cannot be maintained, and no physical barriers exist in public settings.11
Meanwhile, in the US, the Institute for Health Metrics and Evaluation (IHME) has advocated that wearing non-medical grade masks or face coverings in the general population saves lives and will have a profound effect in limiting COVID-19 transmission by 33 per cent.12 Furthermore analysis from Goldman Sachs suggests that a national face mask mandate could potentially substitute for renewed lockdowns that would otherwise subtract nearly five per cent from GDP.13
Nevertheless there remains a large degree of confusion among the public about the merits or otherwise of wearing face masks. While most accept that wearing masks is mainly about protecting others and that wearing face coverings in crowded places will reduce the likelihood of the spread of droplets, there is more limited understanding that masks will not stop the risk of self-infection if they keep touching their mask and risk contaminating the hands. This suggests that a consistent public education campaign backed up by consistent compliance and support from people in the public eye, is needed.
Even before the evidence on mask wearing started to build, masks were becoming a must-have accessory and, arguably, one of the most popular commodities to emerge from the pandemic. Meanwhile a whole new industry has emerged, from an expansion of traditional mask producers, to clothing manufacturers and even people with sewing machine at home, all pivoting their activities to making face masks. Furthermore, emerging evidence shows that while single use masks are required for healthcare workers, it is possible for masks to be reused by a healthy individual. Even if an individual is asymptomatic, masks may offer clear benefits in reducing the spread of disease.