Masks protect the wearer too — not just everyone around them, new CDC guidance says

The Centers for Disease Control and Prevention said in a report Tuesday that masks protect their wearers from the spread of COVID-19, shifting from its previous stance that masks would mostly benefit people around them.

“Experimental and epidemiological data support community masking to reduce the spread of SARS-CoV-2,” the CDC wrote. “The prevention benefit of masking is derived from the combination of source control and personal protection for the mask wearer.”

COVID-19 is mainly spread through respiratory droplets, which are produced through exhalation, according to the CDC. Larger droplets are more visible and fall out of the air quickly after being released while smaller droplets can be suspended in the air for minutes to hours.

Masks function as “source control” to prevent the spread of virus particles that the wearer exhales and, the CDC now says, they act as “filtration for personal protection” by blocking respiratory droplets.

The guidance cites new studies conducted since the start of the pandemic that show masks can reduce the spread of the virus by more than 70% in some cases. One study showed two infected hairstylists wearing masks prevented the transmission of the virus to 67 clients.

The CDC’s previous language focused on masks’ ability to prevent infected people from spreading COVID-19 to others. “The main protection individuals gain from masking occurs when others in their communities also wear face coverings,” it said.

The new report also provided an economic incentive to mask wearing, saying increasing the number of people who wear masks by 15% could prevent future lockdowns and the accompanying losses of up to $1 trillion.

This story was originally published November 11, 2020 at 9:40 AM with the headline "Masks protect the wearer too — not just everyone around them, new CDC guidance says."