There is no strong evidence to support the general public wearing face masks to protect against Covid-19, researchers have said, although they may offer some protection for the vulnerable or those living with somebody who is ill.
A team from the University of East Anglia (UEA) carried out a rapid review of existing scientific evidence and concluded there was no push to change current UK policy, which does not recommend the widespread use of face masks.
It comes after the US recommended that people wear masks or face coverings in public and the World Health Organisation (WHO) said it was looking at the issue.
Wearing a face mask in shared public places could help protect vulnerable people from #COVID19 – according to @UeaMed research. But the evidence is not strong enough to recommend widespread use of masks in the general population: https://t.co/fFMKKHv5On#ThinkingWithoutBorderspic.twitter.com/gHW3kIU37t
— UEA (@uniofeastanglia) April 6, 2020
The new study, which has not been peer-reviewed, found that widespread use of face masks was not needed.
But experts did find that if both an ill person and those who are well – and who live in the same household – wear masks, the risk of transmission is cut by 19%.
There was also enough evidence to support vulnerable people deciding to use masks for short periods, such as when they are on public transport, visiting shops or using the GP surgery.
Study author Professor Paul Hunter, from UEA’s Norwich Medical School, and an expert in infectious diseases, said: “There has been a lot of debate about whether wearing a face mask could help protect people from Covid-19 and reduce the spread of the disease.
“We wanted to evaluate all the available evidence to see what the best advice for people is.
“We studied when respiratory symptoms appeared that were similar to Covid-19 – fever and cough or sore throat.
“But it’s important to remember that we have not been able to look specifically at Covid-19 because there have been no specific studies to date.”
Lead researcher Dr Julii Brainard, also from UEA’s Norwich Medical School, said of the 31 studies reviewed: “We found that using a face mask and other face coverings had a consistent but small protective effect against influenza-type symptoms while people are out and about in the community.
“People who wore masks, usually surgical grade, were less likely to get respiratory symptoms from casual exposure in the community.
“Something like a sneeze or cough near you would become less likely to cause infection.
“It’s a small reduction in risk, but might be very important to especially vulnerable people.
“Wearing masks at home also seemed to reduce the odds of well housemates becoming ill.
“The risk reduction was greatest – a 19% reduction – if both an ill person and their well contacts wore masks.
“The protective effect is probably small within a home setting because people have lots of repeated types of contact, so there are many ways for the germs to transmit.
“This is why washing hands remains so important.”
She said people can find it difficult to wear masks correctly for many hours over many days.
“They can be uncomfortable, hot, cause skin reactions or simply feel anti-social,” she said.
“Masks also need to be disposed of correctly to prevent transmission.
“And of course, wearing a mask interferes with things like sleep, eating and brushing teeth. It’s impossible to keep them on all the time.”
The team found that wearing face masks was also not that protective during large gatherings, although those examined lasted for several days such as the Hajj, the annual Islamic pilgrimage to Mecca.
“Overall, we found that the evidence was too uncertain to support the widespread use of face masks as a protective measure against Covid-19,” Dr Brainard said.
“However, there is enough evidence to endorse the use of face masks for short periods of time by vulnerable individuals when in transient higher risk situations – such as on public transport or visiting shops.
“Although we can support vulnerable people who choose to wear masks to avoid infection, we want to remind everyone that the people who most need to wear masks, to protect us all, are healthcare workers.”