“It looks like the major route of infection is droplet spread rather than true aerosol,” he said. “Masks may have a marginal positive effect in those situations, or face coverings of some sort.
“Where masks have a role is where distancing may not be possible. So there may be some cases where that is not possible, situations where there is undue crowding when wearing masks may be beneficial to stop the spread.
“It’s important that those coverings are worn properly, that they cover the nose and mouth, and it’s important that people don’t handle their face a lot. There’s a much, much higher risk of transmission from hand to mouth or touching things.”
Sir Patrick added that the evidence for face masks was much stronger in health and social care settings, where the abundance of the virus meant it was “absolutely clear” that staff should have masks. He also pointed out that people should be much more concerned with their proximity to other people, adding that the risk of contracting the virus was significantly increased depending on how close people stand to another person.
“The evidence… is that essentially a minute at two metres is around the same risk as six seconds at one metre,” he said. “The risk at one metre is around 10 to 30 times higher than the risk at two metres.”