The science is pretty clear about one thing – COVID-19 is spread by droplets that come out of infected people's mouths while coughing, sneezing, singing, talking and possibly just breathing.
It is also accepted by most people that wearing a face covering, or mask, cuts the chances of someone – including those who don't know they are infectious – of passing on the virus.
Many countries in the world have told people to wear face masks during the pandemic, with laws making them compulsory in enclosed public spaces such as shops and on public transport. Some countries also made them compulsory when outside the home.
But while the UK cites South Korea and others as role models for a "test, track and trace" approach to defeating the virus, it has for months rejected the other measure these countries had to stop the spread, which is the mass wearing of face masks.
Amid growing pressure, the position has been changing and the UK government has now said face coverings will be compulsory on public transport in England – although only from 15 June.、
In Europe, Czechia, Slovakia and Austria acted early and have a low infection and death rate, while Italy, France and Spain have all since taken similar steps and seen their infection rates fall – but the UK has remained skeptical about face coverings. Indeed, in the early stages of the pandemic using face masks was actively discouraged, with the message that they should be reserved for health workers.
It is worth mentioning that the UK view of face masks has been fairly closely aligned with that of the World Health Organization, which says there is mixed evidence of the benefits of general wearing of face masks and says they should only be used in addition to social distancing and other protective measures, or in places where social distancing is not possible.
While the effectiveness of face masks against catching the coronavirus is a much-discussed topic, health experts agree that in most cases wearing a mask is better than having no protection at all.
The World Health Organization (WHO) says that because the novel coronavirus is a respiratory disease and is passed on through droplets coming out of the mouth and nose while coughing or sneezing, it is important to practise respiratory etiquette and guard the face from coming into contact with these droplets or spreading them.