Wearing a cloth mask over a surgical mask or a tightly fitted cover is more effective in decreasing the spread of COVID-19, according to a study released Wednesday from the Centers for Disease Control and Prevention (CDC).
The agency conducted multiple lab experiments that spaced two artificial heads six feet apart to measure the best protection method against the transmission of particles carrying COVID-19. The results showed that virus transmission could be reduced by 96.5 percent if an infected individual and an uninfected individual both wore two cloth and surgical masks or a tightly fitted surgical cover.
Researchers found that only wearing one mask blocked approximately 40 percent of particles in another experiment. In contrast, a combination of a cloth mask over a surgical mask (double-masking) stopped particles by over 92 percent.
The CDC emphasized that if a medical mask is worn alone with a “mask fitter,” it could still significantly improve the individual’s protection.
“The effectiveness of cloth and medical procedure masks can be improved by ensuring that they are well fitted to the contours of the face to prevent leakage of air around the masks’ edges,” the CDC said.
Dr. John Brooks, the study’s lead author, cautioned that the mask findings were conducted in a controlled laboratory environment, so it is unclear how their recommendations will perform in the natural world.
CDC Director Rochelle Walensky announced the finding during a news conference on Wednesday; however, she noted that the recent results do not change the agency’s official recommendations “about who should wear a mask or when they should wear one.” (RELATED: White House Announces New CDC Mask Guidance, Three New Mass Vaccination Sites In Texas)
“I want to be clear that these new scientific data released today do not change the specific recommendations about who should wear a mask or when they should wear one, but they do provide new information on why wearing a well-fitting mask is so important to protect you and others,” Walensky said.
“We continue to recommend that masks should have two or more layers, completely cover your nose and mouth and fit snugly against your nose and the size of your face,” she added.
The CDC’s based their experiments on masking ideas from aerosol transmission expert Lindsay Marr and Dr. Monica Gandhi at the University of California in San Francisco, according to the New York Times.
During Wednesday’s briefing, White House coronavirus advisor Jeff Zients also revealed that the federal government would construct three new vaccination centers at sports stadiums in Texas. Zients said the sites would open to the public by the week of Feb. 22, and claimed it would result in 10,000 daily vaccinations.