Are masks really effective in preventing the spread of coronavirus infections?

This is part 34 of our coronavirus FAQ. Click here to read other installments: #Coronavirus the facts. Find the latest information and answers from experts on everything COVID-19.

It is unclear if masks fully prevent infection with the virus

Experts say it is not clear whether face masks can prevent infection. The widely used disposable masks do not fully block viruses, so any efficacy in preventing infection is believed to be limited.

We hear news of doctors and nurses getting infected despite wearing masks. Are masks really effective?

In healthcare settings, workers wear masks in combination with various other protective measures based on cumulative expertise. Masks alone are not expected to provide enough protection.

Preparation needed to use N95 masks properly

N95 masks are high-performance medical masks that many healthcare workers wear in intensive care units. They can filter out viruses but pose problems, such as making it harder to breathe. To properly use N95 masks, it's necessary to learn beforehand the correct way to wear them.

No matter what kind of mask you wear, touching your face before disinfecting your hands will increase the risk of infection.

When infected people wear masks, the risk of infection is largely reduced

On the other hand, when infected people wear masks, masks are said to significantly reduce the risk of spreading the virus to others. So far, it is known that the novel coronavirus is primarily transmitted through respiratory droplets. It is also known that an infected person emits high amounts of the virus from about two days before showing symptoms through to immediately after they develop. It is said that wearing a mask greatly reduces the dispersal of droplets from coughing and sneezing, as well as of micro-droplets, which are very small particles emitted while talking.

There are various views on masks but their use is recommended

Omi Shigeru, former deputy head of the Japanese government's panel of experts and currently the head of the government subcommittee on coronavirus measures, said to reporters on May 4 that he wants everyone, regardless of whether they have symptoms or not, to wear a mask to reduce the risk of spreading the virus. Omi said that although there are various views on the use of masks, a general consensus has been reached in other countries and at the World Health Organization.

This information was accurate as of July 3, 2020.

Supercomputer study points way to better infection prevention