Topic: CDC study finds two masks are better than one vs. COVID-19
U.S. government researchers found that two masks are better than one in slowing coronavirus spread, but health officials stopped short of recommending that everyone double up.
The Centers for Disease Control and Prevention on Wednesday reported the results of a lab experiment that spaced two artificial heads 6 feet from each other and checked to see how many coronavirus-sized particles spewed by one were inhaled by the other.
The researchers found that wearing one mask — surgical or cloth — blocked around 40% of the particles coming toward the head that was breathing in. When a cloth mask was worn on top of a surgical mask, about 80% were blocked.
When both the exhaling and inhaling heads were double-masked, more than 95% of the particles were blocked, said the CDC’s Dr. John Brooks.
“The first challenge is to get as many as people as possible masking. And then for those that do mask, to help them get the best benefit out of that mask,” Brooks said.
The study had many limitations: The researchers used one brand of surgical mask and one kind of cloth mask, and it’s not clear if results would be the same with every product. But it echoes some earlier research that suggests two masks are better than one.
“It works,” Brooks said.
The CDC also was updating its guidance to address wearing two masks. If done correctly, a cloth mask worn over a surgical mask can tighten the gaps around the mask’s edges that can let virus particles in, the CDC said.
The agency also said it was taking down a do-it-yourself page, which went up last year when masks were in short supply and the CDC was encouraging people to take steps to interrupt viral transmission.
Some Americans have already started doubling up. Experts believe that’s at least partly out of concern about new strains of coronavirus that have been found to spread more easily than the one that has driven the U.S. epidemic for the past year.
Topic Discussed: CDC study finds two masks are better than one vs. COVID-19