Despite months of ministers telling the public not to wear face masks, the government has confirmed it does now want people to wear face coverings.
On Tuesday, health secretary Matt Hancock will announce that face coverings are to be compulsory in shops in England from 24 July.
The announcement comes after Scotland made face coverings mandatory in shops on 10 July, and follows the decision to require their use on public transport in England from 15 June.
The move is designed to prevent an upsurge in coronavirus infections as the country continues to relax lockdown measures, with non-essential shops and restaurants now allowed to reopen.
This also follows a change in advice in mid-May, which recommended people wore face coverings in places it was hard to social distance - like shops and public transport - but this was not made mandatory.
The government's original 50 page plan says: "As more people return to work, there will be more movement outside people's immediate household.
"This increased mobility means the government is now advising that people should aim to wear a face covering in enclosed spaces where social distancing is not always possible and they come into contact with others that they do not normally meet, for example on public transport or in some shops."
Very young children and those with disabilities or respiratory problems will be exempt from the new rules.
The government in Scotland first recommended people wear masks in enclosed public spaces on 28 April: first Minister Nicola Sturgeon said there could be "some benefit" in places where social distancing was otherwise difficult.
So do face masks stop people contracting the virus or just stop those who might be otherwise asymptomatic from unknowingly passing it on?
Do face masks help protect you?
On 8 April the World Health Organisation said there was no evidence to suggest wearing a face mask outside prevented healthy people from picking up Covid-19.
The study found masks don’t necessarily stop healthy people from catching Covid-19 but do stop people spreading the virus further.
It was based on a review of evidence from Hong Kong that suggested widespread use of face masks may have reduced the spread.
Professor David Heymann, of the London School of Hygiene and Tropical Medicine, who chaired the WHO’s scientific and technical advisory group, said that unless people were working in healthcare settings, masks are “only for the protection of others, not for the protection of oneself” - which is why the government is now introducing them.
Surgical masks were first introduced into hospitals in the late 1700s but they did not make the transition into public use until the Spanish flu outbreak in 1919. In a clinical setting, such as a hospital ward or theatre, they are primarily meant for preventing visible sprays or splashes of fluid.
A separate study, conducted by the University of Edinburgh, also suggested that wearing a face covering could help reduce the spread of coronavirus from people who are carriers.
The research showed that wearing a covering over the mouth and nose can reduce the forward distance travelled by an exhaled breath by more than 90 per cent. As the breath could contain small droplets of water, some of which may contain traces of the virus, wearing face coverings will be particularly useful for stopping asymptomatic carriers of the virus.
Are there potential problems with wearing masks?
In February Dr Jake Dunning, head of emerging infections and zoonoses [infectious disease spread between humans and animals] at Public Health England, told The Independent that there is “very little evidence of a widespread benefit” in members of the public wearing masks.
Dr Dunning explained there are a number of reasons why they are not effective in stopping people contracting the virus (rather than spreading it). “Face masks must be worn correctly, changed frequently, removed properly, disposed of safely and used in combination with good universal hygiene behaviour in order for them to be effective.”
And most of the paper options being worn do not have a respirator to filter out infectious air particles.
If they are not worn properly and are loose fitting it means that bacteria can easily access the nose and mouth. Experts have also warned coronavirus could enter the body through the eyes.
Even when users do comply with these rules initially, research shows if users wear them for long periods of time they gradually become slack and are less likely to do so.
The study conducted by University of Edinburgh also pointed out that while surgical masks and handmade masks were found to limit the forward flow of a breath, they also enabled strong jets of air to escape from the back and sides.
Only masks that formed a tight seal with the face were found to prevent the escape of virus-laden fluid particles, the team said.
What other research has there been on face masks?
Jimmy Whitworth, professor of international public health at the London School of Hygiene and Tropical Medicine, told The Independent: “There’s little evidence they are very effective. They’re more beneficial if you have a virus and don’t want to pass it on than to prevent catching anything.” This corroborates the findings by the WHO.
A 2014 study conducted after the Sars outbreak, where masks were also widely worn in Asia, showed inconclusive results on their effectiveness. “Inconsistent results were found in the systematic review evaluating studies on respiratory protection,” states the report.
What should you also do to protect yourself?
The government, and Dr Dunning, still recommend a robust approach to “good personal, respiratory and hand hygiene” as well as now wearing a face mask.
Social distancing measures of two metres or more should also continue to be observed in public wherever possible to help prevent the spread of infection.
The government has stipulated that people should continue working from home if they can do so and avoid public transport.
If you, or anyone in your household has symptoms, you should be self-isolating and not going outside.