What's the Evidence on Face Masks? What You Heard Was Probably Wrong

Fighting the flu

Studies concerning the flu are more in line with current advice about prioritizing hand washing.
Studies about face masks being helpful are somewhat inconsistent.


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What's the Evidence on Face Masks? What You Heard Was Probably Wrong

What's the Evidence on Face Masks? What You Heard Was Probably Wrong


Key Ideas

Effectiveness of face masks

At the beginning of the current outbreak, there were a lot of assurances from the media, governments and medical organizations that face masks are ineffective and could potentially increase our risk of infection.
But this could prove to be a deadly mistake. There is no strong evidence to support ineffective mask theory.

Face masks and viruses

According to research, face masks (surgical and N95) were the most consistently effective way of reducing the transmission of viruses similar to the new one, if worn properly and consistently.
Consistently wearing a mask in public was associated with a 70% reduction in the risk of catching such viruses in Beijing.

Fighting the flu

Studies concerning the flu are more in line with current advice about prioritizing hand washing.
Studies about face masks being helpful are somewhat inconsistent.

The resistance of face masks

When a person coughs, the droplets are somewhere between 8,000–100,000 nanometers in diameter. Most of these droplets will settle and end up on surfaces pretty quickly. The smaller droplets stay in the air longer but are still large enough that a properly-fitted N95 mask could filter them out since N95 masks are 99.5% effective against particles sized 750 nanometers or bigger.
It still remains important to wash our hands regularly and avoid touching our faces when in public.

N95 respirators vs. surgical masks

  • N95 might filter out smaller particles and also creates a tight seal against your face. They might be a better choice if you are taking care of someone with the new virus.
  • When moved out of hospitals though, research shows that N95 respirators are not significantly more effective than surgical masks.

Fabric masks

They allow larger or smaller particles to pass through. So if you wear a fabric mask, treat it as you would a disposable mask and don’t reuse it without ensuring it has been sterilized.
Even hospitals are using and requesting homemade fabric masks, that’s how bad this shortage is.

The dangers of wearing a face mask

  • You might end up touching your face more often and transferring the virus from your hands to your face. Wash your hands both before and after adjusting or removing your face mask to avoid this.
  • If your mask becomes moist against your skin, viruses could diffuse across the mask and reach your face.



Protection By Face Masks

Due to the Wuhan virus spreading across the world, the use of face masks might seem a good means of protection.

The N95 mask, which is a heavy-duty mask offers better protection (95% of air...

Protect Yourself Wisely
  • Cloth masks, which are reusable and washable, offer no real protection while being potentially harmful in case there is any moisture retention or dirt in them due to their being reused.
  • It is a good practice to wear a mask all the time, especially if you have any respiratory illness.
  • It is advisable to be careful while removing your mask, as a mere touch of your hands on the front of the mask can contaminate it.
  • It is also advisable not to touch your face or nose too much.
  • Constantly and frequently wash your hands, all year round, and get a flu shot, as it is flu season. While a flu shot is not a protection against the virus, it is still advisable to get one.
A common effort

As the global spread of the virus accelerates, this sort of do-it-yourself response to the shortage of personal protective equipment (PPE) is becoming very common, with medical researchers, busines...

Safety of homemade devices

So far, the evidence is insufficient and mixed; there are a few ideas that show promise,  but there is also some concern that improvised measures could make things worse.
The last thing you want is for healthcare workers to have a false sense of protection and perform a risky procedure on a patient.

Making masks

The medical opinion on homemade masks is mixed. None of the everyday materials you could use to make masks work as well as a commercial surgical mask, but the homemade versions do prevent some microbes from getting through, suggesting these substitute masks are better than nothing at all: they could theoretically slow the spread of disease by helping keep the virus from escaping people’s noses and mouths.

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The mask

The mask - a flimsy polymer cup - fits tightly around the face and is capable of filtering 95% of airborne particles, such as viruses, from the air.

The firsts masks were ...

Surgical masks

Doctors started wearing the first surgical masks in 1897. The masks were not designed to prevent airborne disease - that is still not the case today - but to prevent doctors from coughing or sneezing droplets onto wounds during surgery.

The first modern respirator

During 1920, a plague broke out between a shared jurisdiction of China and Russia. The Chinese Imperial Court brought in a young doctor named Lien-teh Wu that determined that the plague was not spread by fleas but through the air. He expanded upon the surgery masks he'd seen in the West, and made it from gauze and cotton and added several layers of cloth to filter inhalations.

When the Spanish flu arrived in 1918, the mask was well-known among scientists and the public.

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