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Coronavirus expert says masks cut infection risk by 77%

Face masks reduce the risk of coronavirus infection by 77 per cent according to new medical research published on Tuesday. 

‘When you are out and about, you cannot tell who is infected and who is not,’ said Professor Raina Macintyre, the head of the biosecurity research program at the University of NSW’s Kirby Institute.  

‘You yourself may be infected and not know it. Especially with the growing evidence of pre-symptomatic and asymptomatic transmission, universal face mask use is an important way to reduce the spread of infection.’

Pictured: A staff member wearing a stylish homemade mask prepares artworks last Thursday for the reopening of the National Gallery of Australia. 

The scientific review of 216 coronavirus studies commissioned by the World Health Organisation found the virus can spread through the air, by aerosolised transmission.

It found an 82 per cent reduction in infection risk at a physical distance of one metre, even though droplets can spray up to eight metres from a person’s mouth.

The review, published in the prestigious medical journal The Lancet, found face masks were 77 percent effective at stopping infection, while respirators were 96 percent effective.

'When you are out and about, you cannot tell who is infected and who is not,' said Professor Raina MacIntyre. Face masks can cut the risk of infection, but social distancing also has to stay

‘When you are out and about, you cannot tell who is infected and who is not,’ said Professor Raina MacIntyre. Face masks can cut the risk of infection, but social distancing also has to stay

This finding has enormous implications for Australia as lockdowns are lifted and people return to public transport and shopping centres.

Professor Raina Macintyre said masks would be useful to prevent transmission.

‘As we resume normal activities and increase social mixing at work and leisure, the risk of transmission will increase,’ she told Daily Mail Australia on Tuesday.

CORONAVIRUS CASES IN AUSTRALIA: 7,221

New South Wales: 3,104

Victoria: 1,663

Queensland: 1,059

Western Australia: 591

South Australia: 440

Tasmania: 228

Australian Capital Territory: 107

Northern Territory: 29

TOTAL CASES: 7,221

RECOVERED: 6,625

DEATHS: 102

‘The infection can spread from people who have no symptoms, so you cannot tell who is infected.

‘Wearing a mask prevents onward transmission from someone who is infected and also may prevent infection in someone who is well.

‘People who have to get on crowded buses or trains, or other crowded spaces may consider wearing a mask.’

Professor MacIntyre wrote a commentary on the research which was also published in The Lancet. 

The study, called Physical distancing, face masks, and eye protection to prevent person-to-person transmission of SARS-CoV-2 and COVID-19: a systematic review and meta-analysis, found that multilayer masks were more protective than single layer masks.

‘This finding is vital to inform the proliferation of home-made cloth mask designs, many of which are single-layered,’ she wrote.

‘A well-designed cloth mask should have water-resistant fabric, multiple layers, and good facial fit.’

‘This study supports universal face mask use … Growing evidence for presymptomatic and asymptomatic transmission of SARS-CoV-2 further supports universal face mask use and distancing.’

Face masks are not a substitute for social distancing, however.

Professor MacIntyre said the study supports the recommendation for a 1.5m physical distancing which should continue as lockdowns lift. 

A shortage of face masks at the start of the pandemic was part of the reason that Australia’s health authorities discouraged public mask-wearing, despite their usefulness in stopping droplet transmission.

People worldwide began making their own homemade masks, putting up instruction videos on YouTube. 

While they are not as good as surgical masks, studies have found they are much better than nothing. 

Professor MacIntyre said it was important to follow sound design principles.

‘You need multiple layers, a fine weave, high thread count, water resistant material and good fit around the face. They should be washed daily or can become contaminated,’ she said. 

Australia’s health authorities continue to discourage public face mask wearing, encouraging them only for people who show symptoms.

This has been the consistent message since Australia’s first coronavirus case, a Chinese man from Wuhan who flew to Melbourne on January 19. 

As evidence mounted that people without symptoms could spread the virus, Daily Mail Australia repeatedly asked the Health Department if they would change their advice.

Face masks have inspired a sense of humour. Pictured:  a tree in Melbourne’s CBD  and a statue of Queensland football legend Wally Lewis in Brisbane both were given masks on Thursday

‘As agreed by all state and territory Chief Health Offices and Australia’s Chief Medical Officer, there is little evidence supporting the widespread use of surgical masks in healthy people to prevent transmission in public,’ said a Health Department spokesman on March 24.

Less than 10 days later the US CDC posted a warning online from Singapore’s Ministry of Health about asymptomatic spreaders.

‘The evidence of presymptomatic transmission in Singapore, in combination with evidence from other studies (9,10) supports the likelihood that viral shedding can occur in the absence of symptoms and before symptom onset,’ the paper said. 

As early as March, Australia’s medical experts were bewildered by the government’s anti-mask stance.

‘Here’s one thing I find very difficult to understand: other countries wear P2 masks to protect themselves. Here, we’re telling people to only wear a mask if you’re sick,’ said ANU College of Health and Medicine Professor Shane Thomas on March 23.

‘I don’t think that’s a good approach at all.’   

When people pull their facemasks down to their chin, or leave their noses poking out, they don't work. They must be fitted over the nose and mouth at all times to be of any use

When people pull their facemasks down to their chin, or leave their noses poking out, they don’t work. They must be fitted over the nose and mouth at all times to be of any use

Face shields provide added protection, but with physical distancing plus a face mask they would not be needed by ordinary people in public

Face shields provide added protection, but with physical distancing plus a face mask they would not be needed by ordinary people in public

In the months that followed, scientists firmly established that coronavirus was spread by asymptomatic people, and that masks reduce transmission by providing a barrier to droplets. 

Yet by the end of April, the Health Department along with peak doctors’ association the Royal Australian College of General Practitioners were still discouraging mask use.

For months, Australia's Health Department only recommended face mask use for people who knew they were sick or had symptoms, despite published medical evidence of transmission in people without symptoms - who may not even know they had the virus

For months, Australia’s Health Department only recommended face mask use for people who knew they were sick or had symptoms, despite published medical evidence of transmission in people without symptoms – who may not even know they had the virus

‘Whilst surgical masks can play a role in preventing people who have COVID-19 from spreading it to others, current advice is that well members of general public do not need to wear one,’ said RACGP president Harry Nespolon on April 27. 

‘There is little evidence supporting the widespread use of surgical masks in healthy people to prevent transmission in public,’ the Health Department advised again. 

Australia’s Chief Medical Officer Brendan Murphy softened his stance slightly on Friday, telling reporters that on crowded public transport, people ‘may choose to wear masks’ when it wasn’t possible to maintain a 1.5m distance.

The Health Department is still discouraging widespread facemask use despite new studies showing it reduces the spread of infection.  This is important as lockdown eases and people who might not know they even have the virus mingle on public transport and in shops

The Health Department is still discouraging widespread facemask use despite new studies showing it reduces the spread of infection.  This is important as lockdown eases and people who might not know they even have the virus mingle on public transport and in shops

However, face masks work best to protect the people around the wearer, summed up by the saying: ‘my mask protects you, your mask protects me’. 

If a person with coronavirus chooses not to wear a mask, they could infect everyone around them – even those who are wearing masks themselves. 

That is why universal mask use has been encouraged in many countries overseas including the US, Israel, South Korea, Sri Lanka, Hong Kong and Japan. 

However, Australia’s Health Department is still discouraging universal mask use.

‘In Australia the routine use of face masks in the community is currently not recommended, while the rate of community transmission of COVID-19 is low,’ said a Health Department spokesperson on Sunday.

Mask wearers have become stigmatised and are often assumed to be sick.

‘In Australia I have heard of people being abused for wearing a mask,’ said Professor MacIntyre.

‘We need to make sure this does not happen, and positive messaging is important.’

Read more at DailyMail.co.uk


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