Facts about face masks: Should you wear one, are they effective and what kind should you use?

More Aussies are choosing to wear a face mask when out and about to lower coronavirus infection risk, but there’s one type experts warn against.

Should you wear a face mask when out and about to lower the risk of coronavirus infection?

Is it worthwhile donning one when you’re well or are they only recommended for people who are feeling sick?

What type of mask should you wear and can you make your own with an old scarf or bandana?

The issue of face masks in the COVID-19 era has been confusing, complicated and contradictory, but as case numbers jump in Melbourne and Sydney, more Australians are choosing to wear one just to be safe.

Here’s everything you need to know about covering up when going out.

SHOULD YOU WEAR ONE?

The official advice from Australia’s chief medical officer Professor Paul Kelly is that wearing a face mask isn’t necessary.

A new caveat was added last week in the wake of Melbourne’s devastating second wave of coronavirus infections.

Prof Kelly said people living in Greater Melbourne who can’t remain socially distant when out and about for essential reasons should don a mask.

But for the rest of Australia, it’s not a broad recommendation – and that’s something a growing number of health experts disagree with.

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Professor Mark L. Wahlqvist, Head of Medicine at Monash University, said “the value of wearing masks is clear”.

“It was recognised (early) that the virus could behave in aerosol form through human discharge and especially in polluted atmospheres,” Prof Wahlqvist said.

“It was, and is therefore, necessary to use masks to protect ourselves and others.

“The advice in Australia has been muddled because this has not been communicated and it is becoming clear that this was because of short supply at first and then the misrepresentation that masks would be of limited value.”

If the confusing issue of mask-wearing had been tackled early and honestly, he believes Australia could have avoided strict lockdowns and serious health, economic and social consequences.

“We can still turn the tide by the public health leadership recommending and overcoming cultural reservation about mask use, and a policy which promotes them with due regard to affordability and sustainable disposability.”

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There’s still much scientists don’t know about coronavirus, but research indicates it likely spreads via very small particles, microbiologist Associate Prof Taghrid Istivan from RMIT University said.

In addition, it seems that those particles can remain in the atmosphere or be pushed further with air currents, and probably with airconditioning systems.

“Therefore, (face masks are) not only recommended for infected persons to stop the spread of the virus but also to prevent healthy people from getting infected through inhaling the particles carrying the virus,” Associate Prof Istivan said.

Advice released this week by the Centres for Disease Control in the United States reveals that on its best estimate, 40 per cent of people infected with COVID-19 show no symptoms.

“As the focus now is on airborne transmission, in addition to contact transmission, public awareness and clear guidance on the proper and effective use of masks should be considered,” it said.

What type of face mask offers the best protection? Picture: AAP

WHAT’S THE BEST?

No type of face mask provides complete and perfect protection from infectious diseases, epidemiologist Dr Abrar Ahmad Chughtai from UNSW said.

“How well a mask filters out droplets from coughs and sneezes carrying the coronavirus depends on a variety of factors, including the nature of the mask itself and how it’s used,” Dr Chughtai wrote.

But one of the best options for members of the public is a surgical mask, like you’d typically seen worn in hospital settings, he said.

Studies show they are effective at filtering particles from coughs and sneezes. They can be purchased from pharmacies or online.

“Put them on by holding by the ear loops and hooking over the ears,” Dr Chughtaiexplained.

“Make sure you cover the nose, and pull them down under the chin. Pinch the bridge to ensure a good seal around the top of the nose.”

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Surgical masks are effective in helping to reduce the risk of virus transmission, studies show. Picture: AAP

This dog is not wearing its face mask correctly. Picture: AFP

In some areas, available stock of face masks remains tight after a run on supplies in the early stages of the pandemic.

That’s why many people are opting to buy reusable cloth masks – or even make their own.

While they often come in interesting and fashionable fabrics, they’re not a new phenomenon and have been used throughout history, Dr Chughtai said.

“While it’s generally accepted cloth masks don’t do as good a job at filtering out particles from coughs and sneezes as surgical masks, new evidence shows there are several things to look out for when choosing or making a cloth mask.

“Use two or three layers of fabric. Choose fabric with a high thread count – so a tighter weave, for instance, from a good quality sheet is generally better than a fabric (mask) with a looser weave that you can clearly see light through.

“Fabrics made with more than one type of thread, for instance cotton – silk, cotton–chiffon, or cotton–flannel, may be good choices because they provide better filtration and are more comfortable to wear.”

Reusable cloth masks are popular and also help to reduce infection risk. Picture: Nikki Davis-Jones

Make sure a cloth mask fits properly and seals around the face well, he said.

“Cloth masks have the added advantage of not depleting stocks meant for health workers and can be re-used. You can wash them with soap and water or household detergents, or preferably in a washing machine at 60C. Put the mask somewhere isolated until you can wash it.”

WHAT SHOULD YOU AVOID?

There have been examples of people fashioning their own face coverings with existing wardrobe garments, like scarfs or bandannas.

Dr Chughtai said this should be an absolute last resort, as it’s often difficult to get a good fit and the materials they’re made from tend to have a loose weave.

Using a bandana or scarf as a makeshift face mask is unlikely to offer much protection and should be a last resort.

There are also no studies into the effectiveness of a scarf or bandana wrapped around the mouth and nose reducing infection risk.

“But with many cases of COVID-19 arising without symptoms, a bandana or scarf may provide some protection and prevent spread of infection from sick people.”

As a final note, he reiterated that any measure designed to lower risk should be combined with good hand hygiene and physical distancing.