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Masks Protect Wearers, Too, CDC Acknowledges
The agency catches up to what scientists have been saying, adding another reason to mask up
Perhaps people who aren’t willing to don a face covering in the interest of protecting others will be motivated by selfish interests: Masks protect those who wear them from the coronavirus, too, the U.S. Centers for Disease Control and Prevention now says.
It’s a stance leading scientists in the fields of aerosol research and infectious diseases had already concluded, after recent research dispelled the earlier notion that masks were useful mostly just for protecting others from an infected person who wore one.
“Masks are primarily intended to reduce the emission of virus-laden droplets (‘source control’), which is especially relevant for asymptomatic or presymptomatic infected wearers who feel well and may be unaware of their infectiousness to others, and who are estimated to account for more than 50% of transmissions,” the CDC states. “Masks also help reduce inhalation of these droplets by the wearer (‘filtration for personal protection’).”
Well-fitting masks made of the right materials help reduce infectious particles from getting out or in, according to says Linsey Marr, PhD, a scientist at Virginia Tech whose lab studies the effectiveness of various mask types.
“If it fits well with no gaps and you have at least a couple of layers of densely woven material, then it probably protects you against at least half if not 80% or more of the droplets and aerosols that we think are most important for transmission,” Marr has said previously.
Disposable surgical masks are a solid choice, experts say, but their environmental impact makes them an imperfect option for many people. Homemade face coverings and reusable masks can be very effective, too. [See Elemental’s complete guide to choosing, making and wearing masks.]