Can ANY mask really protect you from the coronavirus?
International health chiefs last week declared a ‘global emergency’ and the first cases of the deadly coronavirus, inevitably, emerged in the UK.
A further 83 Britons and three Irish citizens have now been evacuated from Wuhan – where the virus was first recognised – and are finishing their period of quarantine in a Merseyside hospital.
Health bosses here and over in the UK have reassured the public about ‘robust measures’ already being in place to prevent the spread of the illness. With the number of confirmed cases soaring worldwide, as well as the toll of deaths, an increasing numberof people want to know: what can I do to best protect myself?
In many Asian countries, face masks – the reusable cloth ones, or the disposable surgical type worn by doctors and nurses – have been a common sight on commuters for decades, often as protection from pollution.
The spectre of successive health outbreaks since SARS in 2002 – including H1N1 ‘swine’ flu, ‘avian’ or bird flu, and MERS – all of which could kill, also means the public are on high alert.
Last week in China, amid nationwide shortages of masks, people began resorting to using bras, plastic bags and containers over theirheads as makeshift protection.
The new virus has so far proved fatal in about three per cent of infected patients. This doesn’t sound high, but it is about the same death rate as the 1918 ‘Spanish’ flu that killed millions worldwide. And that number may well rise. So concern is understandable. But are masks – which, except forbeing worn by a few supermodels and celebrities, have never really caught on in these parts – a good idea?
SOME MASKS COULD BE WORSE THAN USELESS
THERE are three basic types of face mask you can buy. First are washable cloth masks – often sold in bright colours. They’ve become something of a fashion item in Asia.
Then there is the light, loose surgical mask, made of paper and other fibres. These are designed to be thrown away after each use.
Finally, there are close-fitting masks worn by hospital staff – and some cyclists and builders – called the N95 or FFP3 ‘respirators’. These are also single-use.
The effectiveness of each type in any given outbreak will depend on how the virus spreads.
Some viruses travel in larger‘droplets’ of saliva or mucus. These are coughed or sneezed out by an infected person, propelled forward, and don’t float in the air. They can be either directly inhaled or, commonly, picked up from surfaces by the hands, and then transferred when someone touches their face.
Other viruses are airborne or‘aerosol’, and exist in tiny particles of moisture – in our breath and floating in the air – and spread more easily. Despite their popularity, there’s not much evidence that surgical masks are an effective way to stop infection, although they may provide a physical barrier, protecting against any significant spray of saliva or mucus.
However, we don’t yet know how the coronavirus spreads. If it travels via the ‘droplet’ method, as SARS and MERS mainly did, surgical masks may help protect you from particles expelled from coughs or sneezes. But viruses aren’t always one or the other, according to researchers.
Both SARS and MERS also spread, occasionally, via fine aerosols and because most masks do not fit closely around the face, tiny airborne particles could still get through to the mouth and nose.
As Professor Raina MacIntyre, of the University of New South Wales in Sydney, Australia, says: ‘The effectiveness of surgical masks against airborne infections is low, because they do not provide a seal around the face and do not have good filtration.’
And the cloth masks popular in Asia (and make-shift bra masks, in case you were considering one) may be worse than useless.
Prof MacIntyre led the only scientific study of them so far, in 14 hospitals in Hanoi, Vietnam.
‘Cloth masks have no efficacy at all, and may even increase your risk of infection – especially if they are not washed regularly,’ she says.
THE BEST DEFENCE? WASHING YOUR HANDS
DESPITE questions over the effectiveness of masks, worried Chinese are buying them – with retailers selling out and reports of prices soaring ten-fold.
With most medical protective equipment made in China, that shortage could spread. Some European countries are also warning of shortages. You could improvise, of course, with some in China even resorting to orange rinds and plastic bottles cut in half.
But there are, perhaps, more useful things you can do.
The World Health Organisation advises wearing washable or disposable gloves in public, and washing hands regularly with soap or alcohol-based cleaner. Avoid touching doorknobs and other public surfaces. Stand 3ft from sick people and cough and sneeze into a tissue – then throw it away and wash your hands. Don’t share towels.