Surgical or alternative masks in public spaces: their proper use will be a key factor in ensuring their effectiveness as a complement to preventive measures

As part of the fight against COVID-19, the question of widespread mask use among the general public in public spaces is frequently raised. Some countries and cities around the world—including places where mask-wearing had not previously been recommended for the general public in the absence of symptoms—have taken steps in this direction, advocating the use of surgical masks or non-surgical fabric masks1 known as “alternative,” “barrier,” or “general public” ^masks2. In France, the production of alternative masks is growing and is becoming increasingly popular among the public, and the proportion of people reporting having used a mask has risen since late March, reaching 59% on April 20–22³.

An opinion from the High Council for Public Health (HCSP) dated April 24, 2020, regarding the adaptation of barrier measures and social distancing to be implemented among the general public, outside of healthcare and medico-social settings, to control the spread of SARS-CoV-2, “recommends making the wearing of a general-purpose mask mandatory in establishments open to the public, whenever a physical distance of at least 1 meter cannot be guaranteed or if there is doubt about the possibility of organizing and maintaining it.”

In light of the easing of lockdown restrictions announced by the government on May 11, 2020, and the expected increase in public movement in France, it is necessary to assess the risk-benefit ratio of widespread use of surgical or alternative masks in public spaces, which depends on strict adherence to usage recommendations to ensure their effectiveness.

Key Takeaways

• Available data suggest that SARS-CoV-2 transmission is possible from individuals who are infected before symptoms appear, or who have mild symptoms or are asymptomatic.

• The routine use of masks in public spaces to reduce SARS-CoV-2 transmission is under discussion. Studies show a moderate but not statistically significant reduction in respiratory infections when masks are worn in public settings.

• Wearing a mask must be combined with the implementation of barrier measures.

• In a context where surgical mask supplies are limited, these should be reserved primarily for healthcare activities.

• The epidemiological effectiveness of alternative masks has not been established; however, provided they meet certain manufacturing standards and use materials that combine filtration capacity with sufficient breathability, their use could help reduce transmission in the population.

• If the use of alternative masks were to be encouraged, guidelines for manufacturing, use, and maintenance, as well as information on precautions to take (particularly regarding limitations on mask use in children), should be developed and promoted.

• The use of masks could lead to a false sense of security and thus a relaxation of barrier measures and social distancing.

• Simple, visual messages about precautions for use, accompanied by a reminder of the importance of adhering to barrier measures, should be promoted.

How to Use and Make Masks: Instructions

To learn how to use a mask:

• Government website: https://www.gouvernement.fr/info-coronavirus/masques-grand-public

To make a cloth mask following the AFNOR guidelines:

• Government website: https://www.gouvernement.fr/fabriquer-un-masque-tutoriels-et-recommandations

• AFNOR website: https://masques-barrieres.afnor.org/home/faire-mon-masquebarriere

• Montissumasque website, created on the initiative of Prof. Bertrand Dautzenberg: https://montissumasque.com/fabriquer-son-masque/