Can a mask really protect you from Coronavirus?

People around the world are buying face masks amid the coronavirus outbreak. But can a mask really protect you from Coronavirus?

The hard truth is they probably won't protect you from your illness. 

Of the many preventative measures, you can take to protect yourself from the new coronavirus, wearing a face mask is one of the most visible. But for members of the general public, health experts don't think it'll help much.

“There's little harm in it,” Eric Toner, a scientist at Johns Hopkins Center for Health Security, told Business Insider. “But it's not likely to be very effective in preventing it.”

Can a mask really protect your from Coronavirus?
Can a mask really protect you from Coronavirus?

The statistics

Since the coronavirus outbreak started Wuhan, China, in December, more than 81,000 people have been infected and at least 2,760 have died. Cases have been recorded in 40 other countries. (For the latest case total and death toll, see Business Insider's live updates here.)

According to the Centers for Disease Control and Prevention (CDC), the best precautions for the public are the standard, everyday ways to avoid all germs: wash your hands frequently, try not to touch your face, and avoid close contact with sick people.

In healthcare settings, however, the CDC has issued stronger directives: Any patients that present flu-like symptoms or have recently traveled to China's Hubei province should wear surgical masks. That lowers the risk that a potentially infected person could spread the coronavirus to others via saliva or phlegm.

The agency also directed doctors and nurses treating potentially infected patients to wear N95 respirator masks and goggles.

US healthcare providers are preparing for the coronavirus's potential spread in the US. The CDC said on Tuesday that the prevalence of the disease could worsen and that it “might be bad.”

Health and Human Services Secretary Alex Azar said yesterday that the US needs at least 300 million N95 respirator face masks for healthcare workers as the country braces for a potentially rapid spread of the coronavirus. The US currently has 30 million masks.

But for the average person, a mask is still probably not necessary. And as mask shortages continue, buying them up can take them away from medical workers that need them.

Coronavirus outbreak in Wuhan
Coronavirus outbreak in Wuhan

Two types of face masks

Face masks are designed to catch large contaminants and particles. There are two common kinds: surgical masks and N95 respirators.

N95 respirators filter out most airborne particles from the surrounding air, preventing wearers from breathing in particles down to 0.3 microns in diameter. These types of masks are often used when air quality is poor due to wildfire smoke or pollution, and they're designed to fit tightly against one's face.

When worn correctly, N95 respirators block out at least 95% of small airborne particles. So the respirators can filter out some droplets carrying coronavirus. The coronavirus itself measures between .05 and 0.2 microns in diameter, according to a recent article in The Lancet.

Healthcare workers are required by law to undergo a “fit test” every year to ensure they know how to use N95 respirators properly.

The two types of masks - Surgical masks (left) and N95 respirators (right).
The two types of masks – Surgical masks (left) and N95 respirators (right).

How the mask works

“While you're wearing this mask, somebody sprays something really nasty around you — it's a chemical that makes everybody cough their brains out if it gets in their mouth, and it's a test to see if that mask is really working,” Robert Amler, a former medical officer at the CDC and a dean at New York Medical College, told Business Insider.

More than 3,000 medical workers in China — the epicenter of the outbreak — have gotten infected by the virus.

No health agencies in the US have issued recommendations for the public to wear N95 respirators.

Surgical masks, meanwhile, are designed to keep droplets and splatter from passing from a person's mouth to nearby surfaces or people. So they're primarily meant as a physical barrier to keep healthcare providers or sick people from spreading their own mouth-borne germs to patients.

The fit of a surgical mask is far looser than an N95 respirator, with openings around the edges.

Many people do not wear either type of face mask properly, however — wearers often move the masks to the side to touch their faces throughout the day, breaking the barrier that the mask is supposed to create. This makes the protection ineffective. Extended facial hair, as well, can break the seal.

Anyone exhibiting symptoms should wear a mask, the CDC says. They should also call their doctor before visiting a medical office or hospital.

A Chinese girl wears a protective mask as her mother pushes her on a suitcase to board a train at Beijing Railway station before the annual Spring Festival on January 21, 2020 in Beijing, China.
A Chinese girl wears a protective mask as her mother pushes her on a suitcase to board a train at Beijing Railway station before the annual Spring Festival on January 21, 2020, in Beijing, China.

Sales of face masks are spiking

In Wuhan, China, authorities are requiring all citizens to wear masks in public places. The virus seems to have an incubation period of up to two weeks, so people could be sick and spreading germs before they show any symptoms. The city is currently under quarantine.

Many stores in China and cities around the world have reportedly sold out of masks. Cao Jun, general manager for mask manufacturer Lanhine in China, told Reuters on January 23 that demand had already reached 200 million masks per day. Lachine's normal production rate is 400,000 per day.

3M, which produces goods like Scotch tape and Post-Its, announced on January 28 that it would boost production of face masks.

Americans looking to buy face masks, meanwhile, have depleted many official Amazon sellers. The vendors are warning against counterfeit masks being sold on the site. Resellers on Facebook are charging up to four times the price and also selling fraudulent masks.

When to use a mask

  • If you are healthy, you only need to wear a mask if you are taking care of a person with the suspected 2019-nCoV infection.
  • Wear a mask if you are coughing or sneezing.
  • Masks are effective only when used in combination with frequent hand-cleaning with alcohol-based hand rub or soap and water.
  • If you wear a mask, then you must know how to use it and dispose of it properly.

How to put on, use, take off and dispose of a mask

  • Before putting on a mask, clean hands with alcohol-based hand rub or soap and water.
  • Cover mouth and nose with mask and make sure there are no gaps between your face and the mask.
  • Avoid touching the mask while using it; if you do, clean your hands with alcohol-based hand rub or soap and water.
  • Replace the mask with a new one as soon as it is damp and do not re-use single-use masks.
  • To remove the mask: remove it from behind (do not touch the front of the mask); discard immediately in a closed bin; clean hands with alcohol-based hand rub or soap and water.
A stranger offering sterilizer on public
A stranger offering sterilizer on public

Coronavirus myths

‘Face masks don’t work’

Can a mask really protect you from Coronavirus?

Wearing a face mask is certainly not an iron-clad guarantee that you won’t get sick – viruses can also transmit through the eyes and tiny viral particles, known as aerosols, can penetrate masks. However, masks are effective at capturing droplets, which is a main transmission route of coronavirus, and some studies have estimated a roughly fivefold protection versus no barrier alone (although others have found lower levels of effectiveness).

If you are likely to be in close contact with someone infected, a mask cuts the chance of the disease being passed on. If you’re showing symptoms of coronavirus, or have been diagnosed, wearing a mask can also protect others. So masks are crucial for the health and social care workers looking after patients and are also recommended for family members who need to care for someone who is ill – ideally, both the patient and carer should have a mask.

However, masks will probably make little difference if you’re just walking around town or taking a bus so there is no need to bulk-buy a huge supply.

One of the coronavirus myths
One of the coronavirus myths

‘It is mutating into a more deadly strain’

All viruses accumulate mutations over time and the virus that causes Covid-19 is no different. How widespread different strains of a virus become depends on natural selection – the versions that can propagate quickest and replicate effectively in the body will be the most “successful”. This doesn’t necessarily mean most dangerous for people though, as viruses that kill people rapidly or make them so sick that they are incapacitated may be less likely to be transmitted.

‘It is no more dangerous than winter flu’

Many individuals who get coronavirus will experience nothing worse than seasonal flu symptoms, but the overall profile of the disease, including its mortality rate, looks more serious. At the start of an outbreak, the apparent mortality rate can be an overestimate if a lot of mild cases are being missed. But this week, a WHO expert suggested that this has not been the case with Covid-19. Bruce Aylward, who led an international mission to China to learn about the virus and the country’s response, said the evidence did not suggest that we were only seeing the tip of the iceberg.

 ‘You need to be with an infected person for 10 minutes’

For flu, some hospital guidelines define exposure as being within six feet of an infected person. This includes a person who sneezes or coughs for 10 minutes or longer. However, it is possible to get the virus with shorter interactions or even by picking the virus up from contaminated surfaces. Although, this is thought to be a less common route of transmission.