The government’s chief medical officer says he will continue to wear a face mask when appropriate. We should follow his example. Covid-19 is an infection that is largely spread indoors – particularly in crowded, poorly ventilated areas – through inhaling droplets and aerosols produced by infected people when they cough, sneeze, sing, talk, or breathe. Face masks are a simple method of reducing the risk of infection – but only if they are worn by large numbers of people. The main function of a mask is to reduce the emission of droplets from infected people into the air. The droplets are captured by the mask and hence less virus enters the air. Much of the benefit of wearing face masks goes to other people but they can also benefit the wearer, particularly if a high-specification FFP2 mask is worn that filters out more particles and droplets when the wearer breathes in air.
Wearing face masks will reduce the spread of the coronavirus and help protect others. This is very important in settings where we are in contact with older and more vulnerable people – such as in supermarkets and on public transport. Wearing a mask has no major side effects, and does not change a person’s oxygen or carbon dioxide levels. Widespread wearing of face masks has been an important part of the pandemic control strategies of countries that have been more successful in containing the spread of Covid-19. Vaccines are essential and can protect us from developing a more serious illness. But we must maintain the use of other control measures, such as the use of face masks, until we are past the worst of the Covid-19 pandemic.