Research on how well various types of masks and face coverings protect against coronavirus has varied but experts and politicians have generally leaned towards the idea that the chance of some protection is better than none.
In the UK, face coverings were first made mandatory in for public transport in June and later for shops and other indoor spaces in July.
Here’s what studies have shown so far about whether masks work:
FACE MASKS LOWER VIRUS R RATE (JANUARY 2021)
Researchers at Boston University in the US found wearing face masks is an effective way to stop the spread of the coronavirus.
The study, published in the journal Lancet Digital Health, found a 10 per cent rise in self-reported mask wearing is associated with a three-fold increase in the odds of keeping the R number – the number of others each person with coronavirus infects – below 1.
Co-author of the study Ben Rader, of Boston Children’s Hospital and Boston University, said: ‘An important finding of this research is that mask wearing is not a replacement for physical distancing.’
INFECTIOUS DROPLETS WILL STILL SLIP THROUGH (DECEMBER 2020)
Scientists at New Mexico State University in the US found wearing a cloth mask may not shield the user totally from coronavirus because infected droplets can slip through, but it would significantly reduce how many.
‘Wearing a mask will offer substantial, but not complete, protection to a susceptible person,’ said Dr Krishna Kota, an associate professor at the university who led the research.
The study found while all masks blocked at least 95 per cent of droplets from coughs and sneezes – there was still a risk of the disease being passed on.
A MASK ‘WILL ALWAYS BE BETTER THAN NOTHING’ (DECEMBER 2020)
Research by the University of Massachusetts Lowell and California Baptist University in the US found wearing a used three-layer surgical mask can reduce the number of small droplets that are released into the air by two thirds.
Co-author Dr Jinxiang Xi said: ‘It is natural to think that wearing a mask, no matter new or old, should always be better than nothing.
‘Our results show that this belief is only true for particles larger than five micrometers, but not for fine particles smaller than 2.5 micrometers.’
MASK-WEARERS EQUALLY LIKELY TO CATCH VIRUS (NOVEMBER 2020)
A study by Copenhagen University Hospital in Denmark suggested face masks may only offer the wearer limited protection against Covid infection.
Researchers found there was no statistically significant difference in the number of people who contacted the virus in a group wearing masks in public compared to a group that did not do so.
The study was carried out in April and May when Danish authorities did not recommend wearing face coverings.
MASK LEADS TO THOUSANDS FEWER COUGH DROPLETS (AUGUST 2020)
Research by Edinburgh University in Scotland suggested cloth face masks are effective at reducing the amount of droplets spread by coughing or sneezing.
The findings suggest a person standing two metres from someone coughing without a mask is exposed to 10,000 times more droplets than from someone standing half a metre away wearing a basic single layer mask.
Professor Paul Digard, of the University of Edinburgh’s Roslin Institute, said: ‘The simple message from our research is that face masks work.
‘Wearing a face covering will reduce the probability that someone unknowingly infected with the virus will pass it on.’
N95 MEDICAL MASKS COULD PREVENT 99% OF SPREAD (AUGUST 2020)
A study by Duke University in North Carolina, US, found N95 masks are the most effective masks at reducing the spread of Covid-19.
The research published in the journal Science Advances, studied 14 types of face coverings.
Co-author Dr Eric Westman said: ‘If everyone wore a mask, we could stop up to 99 percent of these droplets before they reach someone else.
‘In the absence of a vaccine or antiviral medicine, it’s the one proven way to protect others as well as yourself.’
SURGICAL COVERINGS JUST AS GOOD AS N95 MASKS (MARCH 2020)
A University of Oxford study published on March 30 last year concluded that surgical face masks are just as effective at preventing respiratory infections as N95 respirators for doctors, nurses and other health care workers.
N95 respirators are made of thick, tightly woven and moulded material that fits tightly over the face and can stop 95 percent of all airborne particles, while surgical masks are thinner, fit more loosely, and more porous.
The Oxford analysis of past studies – which has not yet been peer reviewed – found that surgical masks were worth wearing but any face mask is only as good as other health and hygiene practices.