In previous posts and comments, I have expressed scepticism concerning the supposed utility of face masks, referring to the then advice of the World Health Organization which was that there was no evidence that the wearing of masks by uninfected people in public served a useful purpose.

As of Friday (June 5th 2020), the WHO has changed its advice and now recommends the wearing of non-medical grade face masks in public. There is advice on the sort of mask to be worn and also on the dangers posed by face masks if misused or mishandled. As I am not an expert in such matters, I will not try to summarize their advice but advise you to look at the WHO site yourself.