Up to 20,000 coronavirus deaths in the UK could be prevented if everyone wore a face mask in public, scientists have predicted.
The Institute for Health Metrics and Evaluation (IHME) at the University of Washington published modelling suggesting that 66,780 deaths due to COVID-19 are projected for the UK by 30 October.
Their data suggests the number could be reduced to 48,352 if at least 95% of the population wear face masks in public.
Having initially dismissed the effectiveness of face masks in preventing the spread of infection, the government has changed its stance and now advises everyone to wear a face covering in enclosed public spaces.
UK government guidelines state: “You must wear a face covering at all times on public transport or when attending a hospital as a visitor or outpatient.
“If you can, you should also wear a face covering in other enclosed public spaces where social distancing isn’t possible and where you will come into contact with people you do not normally meet.
“This is most relevant for short periods indoors in crowded areas.”
Face masks are mandatory in shops in Scotland.
In a staged photocall on Wednesday, Rishi Sunak was seen serving customers in a restaurant without wearing any protective clothing.
The chancellor laughed and joked as he served diners, prompting many to ask why he was not following government advice.
“I honestly thought this video was shot pre lockdown. No mask!, no social distancing whatsoever! A clear case of do as i say, not as i do!” said Twitter user Emily Moore.
“Hey @wagamama_uk sort it out, please...no masks, nor visors...,” wrote another.
“Do you let all your staff break procedures by not wearing masks when serving food to the public in the midst of a pandemic? Think I’ll give your place a miss thanks,” said JimNotJim.
Evidence suggests that a face covering might not protect the wearer but, if they are infected, it may provide protection for people they come into close contact with.
Before the government changed its advice, Matt Hancock had previously rejected the need for masks in public places, saying there was only "weak science" to support telling people to wear face coverings in shops as well as on public transport.
In Scotland people must - by law - wear a face covering in shops and on public transport as well as in airports and train and bus stations.
In England people who don't wear a mask on public transport - except for some groups including children under the age of 11 - can be refused travel or even fined.
Face coverings do not have to be worn by children under the age of three or by those who may find it difficult to manage them correctly.
The World Health Organization (WHO) changed its advice in early June to advise in favour of wearing face coverings, after evidence emerged showing that covering the face could help provide a barrier to "infectious droplets" passing from person to person in busy areas.
WHO now recommends that people wear non-medical face coverings on public transport and in work environments where space is limited, making it more difficult to social distance. Those over 60 with underlying health conditions are also being encouraged to wear masks if they're unable to social distance.
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