Swine flu protection - Do Masks work?

We've all seen the pictures of Mexican commuters wearing face masks to protect them from that country's outbreak of deadly swine flu. But is there any evidence the masks actually work?

Well it seems there is. Public health expert Professor Raina MacIntyre researched the protective value of surgical versus P2 masks in 143 NSW families who had a child attend a hospital emergency department because of influenza.

Those parents who wore a surgical or P2 mask while tending to their sick kids were four times less likely to get influenza or other respiratory viruses, the study found.

But there's the rub. Getting people to wear the masks was an uphill battle. Just under half of parents wore their masks on the first day and the rate declined with every day that passed.

Of course, with the world in a frenzy over swine flu, and an effective vaccine unlikely to be available for months, that attitude could be about to change. MacIntyre now expects to see more people using the masks on public transport and in other crowded places.

How masks work

They may not be a great fashion statement, but the principle behind face masks is simple.

Because the influenza virus is transmitted in droplets of water, rather than through the air, placing a protective barrier over your face can block its entry into your mouth or nose.

So when the passenger sitting next to you on the bus coughs and splutters all the way into town, those virus-bearing droplets will stay on the outside of the mask rather than entering your system.

To be effective, you should change your mask roughly every eight hours, or when it becomes moist. If you need to take your mask off, for example, to eat, then you can fold it and put it in a paper bag. It's important to make sure your mask fits correctly; this means it needs to cover your nose and your mouth, and should be secured firmly at the back of your head.

MacIntyre suggests using disposable paper masks (ie surgical masks), which you can buy from pharmacies, as they are cheap and easy to use. And while there's some suggestion surgical masks are not as effective as P2 (or N95) masks, both McIntyre's research and a Melbourne study found surgical masks work just as well. P2 masks filter out smaller particles, but need to be properly fitted around the contours of your face for them to be effective.

Try to touch your face mask as little as possible, remove it using the straps, and dispose of it properly after use. There's not much point collecting the virus on the outside of the mask if you then smear it all over your hands immediately before eating.

You should also make sure you keep used masks away from children.

Other protective measures

It is important to remember, however, that the flu virus can live on surfaces for a couple of hours. That means even if you're wearing a mask it is still possible to catch the flu from your fellow commuters if you haven't washed your hands before putting them near your face.

Apart from wearing a mask, the best way to protect yourself from influenza – and any other infectious disease – is to follow normal good hygiene practices.

"Hand washing is extremely important and very, very protective," says MacIntyre.

You should wash your hands with normal soap and water:

• after removing your mask
• before and after contact with other people
• before and after touching your mouth, nose or eyes
• before you eat.

Alcohol gel, rinses and foams do work, but they are no more effective than soap and water.

You'll also lessen your chances of catching the flu if you keep your hands away from your face.

If you are unlucky enough to pick up influenza, or other respiratory virus, then good sneezing etiquette will help protect those around you from sharing the pain. Don't cough or sneeze into your hand, use a tissue and dispose of it properly when you have finished.

It's also worth teaching children basic infection control principles, such as how to wash their hands properly and to cover their mouths when they cough or sneeze. You might also want to encourage them not to run their hands along surfaces when they are in public places.

ABC Health and Well being, "Fact Buster, Will a face mask protect me from swine flu?" Our expert: Dr Raina MacIntyre, Published 29/04/2009

Find a Distributor of respirators

RCR International distributes P2 respirators that are suitable for Swine Flu protection. They are also suitable for protection against mechanically and thermally generated particles down to 0.3 micron, such as toxic dusts including asbestos, mist and welding fumes. RCR International P2 Respirators are available in folded with valve, conical with valve or conical without a valve. The valve aids in expelling hot air and assists breathing.

A carbon respirator is also available with valve, carbon removes nuisance levels of ozone or organic vapours.