Do masks actually protect against coronavirus?

As coronavirus spreads across the world, Kiwis are looking to protect themselves.

Some pharmacies in New Zealand are selling out of surgical masks and specially ordering respirator masks.

Dunedin Life Pharmacy posted on Facebook saying they "moved earth and sky" to get a shipment of surgical masks. But demand is so high, they've limited supply to five masks per customer. 

Despite their popularity, the masks may not be the best way to protect against the deadly virus.

Surgical masks block liquid droplets, but do not offer full protection against airborne viruses. 

The masks are not sealed, meaning particles can still enter the wearer's nose and mouth. They also leave eyes exposed.

As well as not being fully sealed, the masks may actually increase the risk.

"Sometimes it can actually present some risks, as you're putting your fingers up and down on your face, removing your mask, putting them next to your eyes," said Canada's chief public health officer Dr Theresa Tam earlier this week.

When removing a surgical mask, it is recommended to treat it as if it is contaminated - pulling from the ear straps and disposing of it, rather than just lowering it from the mouth. 

The Center for Disease Control and Prevention (CDC) recommends anyone workers interacting with coronavirus patients or suspected cases wear a stronger kind of mask, known as the N95 respirator, along with other precautions like gloves and eye protectors.

N95 respirators offer more protection. When fitted correctly, these masks are designed to prevent 95 percent of particles from entering the nose and mouth. However, they are not suitable for people with facial hair, or for children, reports New Scientist. 

Another side effect of the respirators is they can make it harder to breathe - not ideal for someone showing signs of being infected by coronavirus such as coughing and shortness of breath.

Coronavirus originated in Wuhan, China and has since spread across the world. Thirteen countries now have people diagnosed with the virus, which causes pneumonia, and in serious cases, organ failure.

There have been no reported cases in New Zealand, but officials from the Ministry of Health say the likelihood of a case emerging is high.

The virus has killed 106 people and a further 4500 people have been infected.