Wearing a face mask doesn't just protect other people from potentially getting infected with the coronavirus, it protects you too, according to updated guidance from the Centers for Disease Control and Prevention.
When the CDC started urging Americans to wear face coverings back in April, the guidance was that masks could prevent an infected person from spreading the virus to others, by reducing the dispersion of respiratory droplets. While this is still the primary intention of wearing masks, the CDC now cites growing evidence that wearing a mask also helps protect the person who puts it on.
"The report indicates that, based on their review of evidence, cloth masks not only block viral particles exhaled by the person wearing the mask, but also provides a filtration by blocking incoming infectious droplets from other people," Dr. Shoshana Ungerleider told CBSN on Thursday.
The more people wear masks consistently and correctly, the stronger the protective benefits become, the CDC said.
SARS-CoV-2, the virus that causes COVID-19, is mostly transmitted by respiratory droplets generated when people cough, sneeze, sing, talk, or breathe. The smallest of these particles can remain airborne for some time.
The CDC report estimated that more than half of transmissions originate from people who aren't showing any symptoms and may not even know they have the virus.
In its new scientific brief, the CDC listed several studies that "have confirmed the benefit of universal masking." It also points to epidemiological studies that show mask-wearing works, including a Beijing study of 124 households in which masks cut virus transmission by 79%, and an outbreak aboard the U.S.S. Theodore Roosevelt in which face coverings helped reduce the infection risk by 70%.
"Each analysis demonstrated that, following directives from organizational and political leadership for universal masking, new infections fell significantly," the report reads.
The new report comes as President-elect Joe Biden urged all Americans to wear masks amid a nationwide surge of coronavirus cases. On Sunday, Utah Governor Gary Herbert ordered a statewide mask mandate in an attempt to stem a surge in coronavirus patient hospitalizations.
The Infectious Diseases Society of America urged "all governors who have not yet enacted mask mandates to do so."
"Enacting mask mandates and creating some kind of accountability in various locals is very important," Dr. Ungerleider told CBSN. "I think a lack of solid, concise public health messaging coming out of the current administration has put us in this situation where wearing a mask is highly politicized and not seen as the act of love or care that it is in protecting other people and those that you love from becoming sick."
The CDC also offered an economic argument, noting that increasing universal masking by 15% could prevent the need for lockdowns and reduce economic losses by up to $1 trillion.
"To me, the bottom line here is that take there is no question that masks work. We should all be wearing them," Ungerleider said. "It's important to wear a mask that fits your face tightly. The thicker the better."