Face masks may have a “weak but positive effect” in reducing the spread of coronavirus, Downing Street has concluded, as ministers continue to consider what advice to issue.
Boris Johnson suggested that coverings will play a part in his May 7 announcement on how the lockdown measures may be eased.
The Prime Minister’s spokesman said: "Ministers are still considering how we move forward with face coverings in terms of the precise advice which we give to the public and once that's ready we will announce it.
"The advice we have received based on the science shows a weak but positive effect in reducing transmission of coronavirus from asymptomatic members of the public where social distancing isn't possible.
"What ministers need to consider is how best to produce advice for the public on the next steps and that work is still ongoing."
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The comments come after a minister suggested face coverings only bring “modest” health benefits and don’t necessarily make a “huge difference”, a government minister has said.
Housing Secretary Robert Jenrick said wearing face masks is a “personal choice” and while they bring modest benefits, they could help boost public confidence.
Speaking to the BBC on Friday, Jenrick said: “The advice in the past has been that face masks have only quite a modest difference from a health perspective.”
He said: “They do help us to protect others, and it might be particularly useful if you’re asymptomatic – so you don’t know if you’ve got symptoms but you could still be spreading the virus.
“The benefits are modest but they might be a way of giving people confidence because many people are understandably very anxious about going out, about returning to the workplace in a safe way.”
Jenrick continued: “It’s a personal choice, if you have a face mask, it’s your choice whether you want to use them, and if you walk around some of our towns and cities today you are seeing more people using them than ever before.
“The advice today is that the difference made by a face covering is quite modest – it doesn’t make a huge difference but it does make some. So it’s your choice.”
The Housing Secretary’s comments echo those of Sir Patrick Vallance, the government’s chief scientific adviser, who said evidence showing that masks prevent transmission of COVID-19 is “quite weak”.
Concerns have also been raised that continued use of masks by the public could deprive NHS and other key workers from the protective equipment they need.
Cabinet Office Minister Michael Gove also suggested there could be a risk that people would act in a “cavalier” way if told to wear masks.
He told MPs: “The scientific evidence so far says face coverings can have an effect in preventing an individual from spreading the disease to others if they have it and are asymptomatic.
“But there is also a worry that some people may think that wearing a mask protects themselves, as distinct to protecting others, and therefore they may behave in a manner that is slightly more cavalier.”