If face masks really stop Covid, then why do so many of us still get it?

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Stifling. Itchy. Dehumanizing. Oppressive. Deeply anti-British. Just a few of the terms used to describe the experience of wearing a mask.

Despite the discomfort, we put up with it for the health of our nation and so we are told to do what we can to end this nightmare as quickly as possible.

And last week, the Mayor of London, Sadiq Khan, argued that we should extend the annoyance outside – into our main streets – to protect our fellow Christmas shoppers.

The World Health Organization (WHO) urges us to wear masks around the Christmas table.

Despite the discomfort, we support the wearing of masks for the health of our nation and, therefore, we are told to do what we can to end this nightmare, as quickly as possible.

But does all that wearing a mask help? Surveys show that three-quarters of Britons wear masks in mandatory areas – public transport, offices, pubs and restaurants when not seated at a table, and most indoor spaces.

Yet the infection is still spreading at a rate that is forcing 38 million Britons to ban mingling indoors with anyone outside their homes.

Last week cases increased in all parts of England except Yorkshire and the Humber, and in some areas the infection rate has climbed to twice what it was in April .

So are they unnecessary after all? If Mr. Khan’s logic is to be believed, maybe the problem is that we don’t wear them outside – surrounded by crowds of people. But studies show that only one in 100 cases is transmitted externally.

Countries that have implemented compulsory mask wearing outdoors, such as Spain and Italy, have not been spared from further devastating waves.

Inside, the theory is that the masks trap viral particles that are expelled from an infected person’s mouth or nose when they cough, drool, sneeze, or speak. In the past six months, some studies seem to have shown their effectiveness in doing this. In June, The Lancet compiled data from 172 studies from 16 countries and concluded that two meters social distancing and wearing a face mask reduced the risk of contracting Covid.

A US study, published in August, found rates to be four times lower in countries where mask wear was considered a norm or was mandated by the government.

In the UK, most of the data has concluded that masks are, at the population level, effective when an infected person is wearing them.

A sign telling people to wear face masks on display in London earlier this year.  Surveys show three quarters of Britons wear masks in mandatory areas

A sign telling people to wear face masks on display in London earlier this year. Surveys show three quarters of Britons wear masks in mandatory areas

Professor Paul Digard, a virologist at the University of Edinburgh involved in the trial, explains: “A major source of transmission is through droplets of fluid – like coughs and sneezes – which send the virus into the air.

“Covid particles are too small to be stopped by a mask, but they often travel in larger water droplets. These droplets are large enough to be trapped in a mask.

But droplets aren’t the only way to spread the virus. In July, the WHO released new guidelines for viral spread through smaller, lighter particles that travel through the air – like smoke or dust – and persist long after the infected person leaves the area.

“There is little that masks can do to stop airborne transmission,” says Professor Digard. “The Covid particles that are not contained in the water droplets are too small to be stopped by them. However, he adds that only a minority of infections are spread by airborne infections because the virus particles do not stay in the air for too long. But there is little evidence of effectiveness in real life.

Most of the research carried out in the spring and summer involved laboratory studies using artificial respirators to simulate human coughs and observe the effectiveness of masks limiting the movement of water droplets.

Last week, the Mayor of London, Sadiq Khan, argued that we should extend the annoyance outside - into our high streets - to protect our fellow Christmas shoppers.

Last week, the Mayor of London, Sadiq Khan, argued that we should extend the annoyance outside – into our main streets – to protect our fellow Christmas shoppers.

A real-world trial, involving 6,000 participants wearing surgical masks at all times when in public, was inconclusive. Professor Jimmy Whitworth, London School of Hygiene and Tropical Medicine, adds: “Even real-world studies are hampered by the fact that you don’t know if participants are actually wearing the mask correctly – if at all. “

There is little research available on whether we are wearing masks correctly, but experts say this is an aspect of the debate that is often overlooked. Professor Whitworth said: “Studies show it’s effective, but it has to be worn correctly – with your mouth and nose covered.

As to whether they prevent the virus from entering, protecting the carrier, the evidence is even more fragile.

Studies do not take into account unknown variables – such as how often people wear them. “Masks are unlikely to prevent you from catching the virus, but they are much more likely to trap infected water droplets coming out of your mouth,” says Professor Digard.

Masks are a less powerful tool than the other key mitigation measure – social distancing. Yet, according to a national poll in October, 42% of Britons had broken the two-meter rule at some point, compared with just a tenth who had not worn a face mask in a store.

Professor Whitworth says: “The two most important risk factors for catching Covid are lack of ventilation and congestion. The more air you share with others, the more likely you are to catch it.

Yet masks, we have come to believe, will lessen the damage caused by crowds.

The official advice is to wear face masks when social distancing is not possible. The data suggests it’s actually correct and scientists say if it weren’t for the masks, the cases could be even higher.

Commuters pictured wearing face masks at Canada Water station in London on the Jubilee Line in November this year

Commuters pictured wearing face masks at Canada Water station in London on the Jubilee Line in November this year

Figures from Public Health England show that the majority of outbreaks between August and October occurred in schools and workplaces – environments where mask wear is low. Only children over 12 years old should wear a mask. They are allowed to take them off at their desks, while many workplaces do not require masks to be worn. Meanwhile, pubs and restaurants, where masks are mandatory and only small groups can congregate, accounted for around 5% of all outbreaks.

Another hot spot is inside each other’s houses, where people rarely wear masks.

The truth is, we don’t know for sure what effect masks have. “But common sense tells us it’s worth doing,” says Professor Whitworth.

Professor Digard sees laboratory studies as sufficient evidence that masks offer more protection than not – and not always directly.

Italian research shows that wearing masks makes us more likely to respect social distancing and other restrictions related to Covid. Professor Julian Tang, University of Leicester, said: “Scientists speculated that the masks would give people a false sense of security and make them complacent. But studies show the opposite to be true. When people put on masks, they become more aware of the people around them and play by the rules.

Ultimately, while wearing a mask offers a small benefit, it comes with little to no risk.

As Professor Digard puts it: “What is there to lose in wearing one? “

Don’t forget to wash yours …

Britain’s poor hygiene habits may explain why masks are not having the desired effect.

In October, a YouGov poll found that 85% of Britons did not wash reusable face coverings properly between uses. Shockingly, 15% said they never washed them.

In September, the government’s science advisory group, SAGE, released a report urging people to wash their masks properly, warning that dirty masks could increase the risk of transmission of Covid-19.

Professor Julian Tang said, “Studies show that touching an unwashed mask could lead to transmission of Covid if the virus is present on the surface.

Likewise, the reuse of disposable masks is a problem. A study from the University of Oxford found that continued use of disposable surgical masks for more than six hours relaxes the tissue, making it less able to trap expelled droplets and airborne particles.

Those clogged with dirt attracted viral particles that stuck to the material, increasing the risk of infecting the wearer.

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