Cloth face masks offer two-way protection, benefitting both the wearer and those around them, according to updated guidance from the Centers for Disease Control and Prevention (CDC).
Previously, the CDC had emphasized the role of cloth face masks in blocking the release of infectious virus particles when the wearer coughs, sneezes or talks, thus protecting others from someone who has COVID-19.
But this week, the agency updated its guidelines to say that cloth masks also provide "filtration for personal protection," meaning the masks can filter out potentially infectious droplets from the air, and thus protect the wearer.
The CDC notes that the effectiveness of cloth masks at filtering particles has varied widely across studies, but masks with multiple layers of cloth and higher thread counts have shown superior protection compared with those that have a single layer and low thread count. In some cases, cloth face masks have been shown to filter nearly 50% of very small particles (less than 1 micron) from the air, the agency said. (Fine droplets, also known as aerosols, are no bigger than 10 microns and are released when people talk, potentially carrying infectious particles.)
In the new guidance, the CDC cited numerous studies suggesting the two-way benefit of masks. For example, in a study of a COVID-19 outbreak on the USS Theodore Roosevelt aircraft carrier, use of face masks on board was tied with a 70% reduction in infection risk.
In addition, several studies have found that state and local mandates for wearing masks in public are tied with significant reductions in new cases.
The CDC concludes that the overall benefit of masking increases as more people in the community wear masks.
"Adopting universal masking policies can help avert future lockdowns, especially if combined with other non-pharmaceutical interventions such as social distancing, hand hygiene and adequate ventilation," the agency said.
Originally published on Live Science.
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Rachael is a Live Science contributor, and was a former channel editor and senior writer for Live Science between 2010 and 2022. She has a master's degree in journalism from New York University's Science, Health and Environmental Reporting Program. She also holds a B.S. in molecular biology and an M.S. in biology from the University of California, San Diego. Her work has appeared in Scienceline, The Washington Post and Scientific American.
There are about 80 studies on PubMed showing that viruses are too small and go right through masks. Evidently CDC hasn't read these. Best way to protect yourself is to boost your immune system & when you cough cover your mouth. When you're sick, stay home. Also, if you believe vaccines work, then you shouldn't worry about what anyone else does because you should be protected.Reply
plantlady said:viruses are too small and go right through masks.
Any publications about the virus alone passing through a "mask" would be true, as it is only about 100 nm in diameter, so only high containment PPE is going to stop it. That does not mean regular "masks" do not help prevent the spread of the virus within real, human populations, where it is transmitted on much larger particles, as everyone should know by now.
There is ample scientific evidence that masks reduce the spread of this virus (1, 2), and would reduce the spread of flu and cold viruses if people wore them during those seasons as well. This is not open to debate. It is scientific reality at its finest - directly helping people! The hard data is in on masks. They absolutely help. There can be no doubt.
All infectious respiratory agents are spread by exhaled aerosols and droplets from the carrier to the unsuspecting target. This issue about the value of masks seems to be a no-brainer, but that designation may have different meanings for this situation.....
Rest assured there is no doubt that the use of face masks, properly made and worn properly, can be very significant in reducing infectivity by minimizing spread of COVID-19. Wear a mask - it protects everyone. The CDC has the hard data to prove it.
Bullshit!Chem721 said:Rest assured there is no doubt that the use of face masks, properly made and worn properly, can be very significant in reducing infectivity by minimizing spread of COVID-19. Wear a mask - it protects everyone. The CDC has the hard data to prove it.
Even the CDC does not state there is any significant protection. Only biased non-peer reviewed studies published by anti-Trumpers after this mess got politicized would not say that masks offer any form of significant protection.
See this Cambridge peer reviewed meta-analysis:
Face masks to prevent transmission of influenza virus: a systematic review