How much extra protection do masks give from viruses?

Why are we asking this now?

Boris Johnson gave a press conference on Monday evening in which he made clear he expects the UK to complete its roadmap out of lockdown on 19 July, ending the last restrictions imposed on the British public to thwart the coronavirus pandemic.

Insisting at Downing Street that we must “learn to live with” Covid-19 and that it is a case of “now or never” on reopening, the prime minister announced that social distancing measures would cease to be a legal requirement other than at airports, employees will be able to return to offices, capacity limits on entertainment venues would cease, care homes can reopen their doors to visitors and table service can end in restaurants and bars.

While the decision was broadly welcomed by trade bodies, the PM was branded “reckless” by Labour leader Sir Keir Starmer and dissent was also expressed by the mayors of London and Manchester, Sadiq Khan and Andy Burnham, with many uneasy about the ongoing rise in Covid cases numbers, currently at their highest level since January and forecast to hit 50,000 a day by “Freedom Day”.

What are the rules for mask-wearing after 19 July?

The requirement to wear masks in public will be lifted, except in “enclosed and crowded” spaces where guidance will be offered, leaving the matter largely down to individual discretion, according to the PM.

Local transport authorities and commercial airlines will be entitled to set their own rules for travellers but there will be no laws requiring the wearing of face coverings on public transport, a matter of particular concern to Mr Khan and Mr Burnham.

As for places of work, the PM did not unveil any new employee rights measures, leaving workers without legal backing should they feel uncomfortable and refuse to work in places without mask mandates in place.

What have scientists said about the rule changes?

Professor Stephen Reicher, a psychologist at the University of Edinburgh and an outspoken member of the government’s Scientific Advisory Group for Emergencies (Sage), tweeted his disdain with a dig at new health secretary Sajid Javid, writing: “It is frightening to have a ‘health’ secretary who still thinks Covid is flu, who is unconcerned at levels of infection, who doesn’t realise that those who do best for health also do best for the economy, who wants to ditch all protections while only half of us are vaccinated.

“The key message of the pandemic is ‘this isn’t an ‘I’ thing, it’s a ‘we’ thing’. Your behaviour affects my health. Get your head around the ‘we’ concept.”

Professor Adam Finn of the government’s Joint Committee on Vaccination and Immunisation, was also concerned, warning that the pandemic could still spiral “out of control” in the UK.

“I shall certainly be continuing to wear a mask if I have got any symptoms, or if I am in an enclosed space with lots of other people for a prolonged period of time,” he said.

Dr Chaand Nagpaul, chair of the British Medical Association, also voiced his anxiety: “As case numbers continue to rise at an alarming rate due to the rapid transmission of the Delta variant and an increase in people mixing with one another, it makes no sense to remove restrictions in their entirety in just over two weeks’ time.”

What is the science behind masks?

The messaging has not always been clear on the benefit of face masks, with the UK failing to make them mandatory on public transport until 15 June last year and inside public venues until 24 July.

“There is no specific evidence to suggest that the wearing of masks by the mass population has any potential benefit,” said Dr Mike Ryan, executive director of the World Health Organisation (WHO)’s emergencies programme back in March 2020 at the onset of the global pandemic. “In fact, there’s some evidence to suggest the opposite in the misuse of wearing a mask properly or fitting it properly.”

The WHO subsequently revised its opinion three months later, citing “evolving knowledge”, recommending governments ask everyone to wear face masks in public places to stop the spread.

While that initial confusion was deeply unhelpful in establishing a culture of mask-wearing around the world, the UK government website now offers a clear explanation of its benefits, advising readers that the coronavirus “spreads from person to person through: small droplets, clouds of tiny airborne particles known as aerosols, direct contact.”

It continues: “The best available scientific evidence is that, when used correctly, wearing a face covering may reduce the spread of coronavirus droplets in certain circumstances, helping to protect others.

“Because face coverings are mainly intended to protect others from coronavirus, rather than the wearer, they are not a replacement for social distancing and regular hand washing.”

Dr Robert White, lecturer in virology at Imperial College London, told The Independent that masks “impede the flow of water droplets into the air, and condense them on the mouth, by filtering them onto the mask”.

Academic research projects have also repeatedly proven their efficacy, with one report published in The Lancet on 3 June 2020 - analysing data from 172 studies in 16 countries - concluding that there is just a three per cent chance of catching Covid when wearing a face covering.

What are the objections to masks?

Not everyone can safely wear a mask.

Some might have a serious underlying condition that prevents them from being able to sport one without suffering breathing difficulties and that requires them to seek an official exemption.

Others - like health minister Helen Whately - might simply take exception to them as an uncomfortable inconvenience they would rather do without, which is certainly understandable to an extent.

This latter group will be the main beneficiaries of Mr Johnson’s decision to make mask-wearing a matter of “personal choice” from 19 July, with Ms Whately telling Sky News she “can’t wait” to cast her’s aside.

But one of the more distressing attitudes to have developed over the course of the pandemic, particularly among conservatives, is that any state requirement to wear masks represents an attack on civil liberties.

This point-of-view was particularly prevalent in the US under Donald Trump last year, when the president and members of his cabinet declined to wear face coverings at public engagements, Mr Trump repeatedly claiming not to be able to understand questions posed by masked reporters at his White House Rose Garden briefings on the pandemic.

Making masks a “culture war” issue ripe for debate on Fox News rather than a simple public health necessity was symptomatic of Mr Trump’s divide and rule approach to political leadership and the issue has largely fallen away under Joe Biden, with the majority now accepting the need to keep transmission low in the wider interests of reopening, however reluctantly.

Mr Trump becoming seriously ill with Covid himself a month before November’s presidential election hardly helped his case and viral videos of angry shoppers berating supermarket staff for attempting to enforce mask mandates are now much less common.

Only the most paranoid and conspiracy-minded still regard masks (or indeed Covid vaccines) as instruments of state “control” but they remain a vocal presence around the world and social media.

More encouragingly, a recent YouGov poll found that as many as two-thirds of Britons intend to carry on wearing face coverings once the rules end, apparently unconvinced by Mr Johnson’s logic.

“Of all the ways the pandemic has impacted our day-to-day lives, wearing a small piece of fabric across my face when I go in a shop is pretty low down on the priority list,” one person told The Independent this week of their decision to persevere.

“For me, it’s a moral duty to protect more vulnerable people,” said another. “We should care enough about each other to keep people safe.”

What are the rules for mask-wearing overseas?

As with everything else concerning the pandemic, the rules differ from one location to another depending on the severity of the Covid situation locally and are subject to change.

In France, masks must be worn in enclosed public spaces while in Greece they must be worn in all public spaces.

Elsewhere, the rules are more convoluted.

In Spain, to take a popular British holiday destination for example, as of 26 June it is no  longer mandatory to wear a face mask outdoors where social distancing of 1.5 metres is in effect. However, there are exceptions in place requiring them to be worn in enclosed public spaces, on public transport and in indoor spaces where different households might mix.

In Portugal, to give another case study, you must wear a mask while walking along promenades and in restaurants and cafes until you are seated and at the beach until you reach your designated spot on the sand.

Meanwhile in Malta, masks are mandatory in all public spaces, indoor and outdoor, for all those aged three and over, with fines levied for non-compliance. Mask-wearing on beaches is advised but no longer required as of 1 June. Also since that date, a maximum of two people have been allowed to remove their masks in outside public spaces if they have been vaccinated and they have an official vaccination certificate. But, currently, only Maltese-issued certificates will be accepted.

Travellers hoping to get away this summer are advised to check the latest rules on the ground before they depart.