This illustration shows a woman wearing two facemasks, a cloth mask over a surgical mask, in Arlington, Virginia, on February 8, 2021.
Olivier Douliery | AFP | Getty Images
Wearing a cloth mask over a surgical mask can help significantly reduce the risk of exposure to Covid-19, according to a new study from the Centers for Disease Control and Prevention.
The CDC researchers said they explored the effectiveness of different masking approaches through laboratory experiments in which they placed two artificial heads 6 feet from one another and measured how many coronavirus-sized particles exhaled by one were inhaled by the other.
The researchers found that wearing just one mask, either surgical or cloth, blocked a little over 40% of the particles. But a cloth mask on top of a surgical mask blocked about 80% of particles. When both of the heads in the experiment wore two masks, more than 95% of the particles were blocked, the researchers found.
CDC Director Dr. Rochelle Walensky said the study’s findings “underscore the importance of wearing a mask correctly and making sure it fits closely and snugly over your nose and mouth.”
Walensky said the agency is not changing its original recommendation that everyone two years and older wear a mask when around people who don’t live in their household. However, the agency will update its guidance on its website “to provide new options on how to improve mask fit,” Walensky said.
Those options include wearing a mask with a moldable nose wire or wearing a cloth mask over a disposable surgical mask, she said. She added that there are new devices called mask fitters that can help cinch a cloth or medical mask and create a tighter fit.
“The bottom line is this: masks work and they work best when they have a good fit and are worn correctly,” she said
The updated guidance is the latest attempt by President Joe Biden‘s administration to provide clear guidance to Americans. Walensky has tasked CDC scientists with reviewing all guidance from the agency that was issued under the previous administration to make sure it’s clear and consistent.
The issue of masking became a contentious one last year as health officials urged Americans to wear masks in public even as President Donald Trump declined for months to appear publicly with a mask.
The updated guidance comes at an important time in the U.S. outbreak. Cases, hospitalizations and deaths are falling, but health officials warn that new, more contagious variants threaten to reverse the country’s progress and cause another surge. Reducing spread of the virus, and of the new variants, is as important as ever as the country races vaccinate the public, but is hampered by constrained supply, health officials say.
Biden has urged all Americans to commit to wearing masks in public for his 100 days in office to help slow the spread of the virus. As of Feb. 1, 14 states and the District of Columbia all had universal masking mandates, the CDC said. Biden has also mandated mask wearing on all federal property and on domestic and international travel, including public buses, trains and planes.
