CDC confirms masks also protect the wearer, outlines which ones are most effective
The Centers for Disease Control and Prevention updated its guidance on masks in a scientific briefing released on Tuesday, confirming that they not only protect those around the wearer from respiratory droplets, but “also help reduce inhalation of these droplets by the wearer.”
Epidemiologists and other officials commended the update on Twitter, suggesting that it confirms the long-supported theory that masks offer more than one benefit. Others expressed hope that it may encourage more people to wear masks, thereby reducing the spread from asymptomatic or presymptomatic individuals, who, studies have shown, may be driving 50 percent of transmission.
On top of highlighting masks’ importance, the organization also outlined what individuals should look for when choosing a mask. Dr. Saskia Popescu, an infection prevention specialist at George Mason University, says the goal should be finding one that offers both “source control” (protection for others) and protection for the wearer. “Things like surgical masks and N95 provide both, which is why we wear them in healthcare,” Popescu tells Yahoo Life. “The cloth masks offer some source control and variable protection for the wearer, but we are still learning to what extent.”
As COVID-19 cases in the U.S. continue to spike, here’s what you need to know about staying safe.
Multilayer masks are key — and surgical masks are a great option
The CDC notes that multilayer masks are effective in that they “block release of exhaled respiratory particles into the environment, along with the microorganisms these particles carry.” Researchers from the University of New South Wales confirmed this in a July study published in Thorax in which they recorded healthy individuals releasing respiratory droplets using and LED lighting system and a high-speed camera.
The individuals were filmed wearing three separate masks: a single-ply mask made from cotton T-shirts and hair ties, a double-ply mask sewn from cotton T-shirts, and a three-ply surgical mask. The three-ply surgical mask provided the most protection, but the two-ply mask provided more protection from droplets produced while coughing or sneezing than the single-ply mask did, leading the experts to conclude that “guidelines on home-made cloth masks should stipulate multiple layers.”
Cloth masks with more than one layer and a high thread count do provide protection
Although there has been debate on whether or not cloth masks offer protection, the CDC endorsed the use of cloth masks in its briefing this week, saying that the face coverings “not only effectively block most large droplets but they can also block the exhalation of fine droplets and particles (also often referred to as aerosols) smaller than 10 microns.”
The organization notes that multilayer cloth masks are particularly effective, blocking “50-70 percent of these fine droplets and particles and limit[ing] the forward spread of those that are not captured.” The CDC added, as other experts have, that masks with higher thread counts offer more protection than those with low thread counts. For more detailed instructions on how to make your own mask, visit the CDC’s information page.
Neck gaiters, unless doubled, do not offer much protection — but are better than nothing
Much confusion circulated this summer about the value of neck gaiters after a Duke University study, designed to find an accessible way to test masks, initially gave the impression that the face covering could make things worse. Since then, experts have clarified that a neck gaiter is unlikely to be causing more spread of the virus and, according to experts at MIT, may actually be “better than nothing.”
Still, in an earlier interview with Yahoo Life, Dr. Amesh A. Adalja, senior scholar at the Johns Hopkins Center for Health Security, advised against wearing them. “I probably would stay away from the gaiters as a mask of choice because we at least have some evidence that some don’t necessarily work,” Adalja said. “Until we get more data, I would not probably recommend the use of gaiter.” But for neck-gaiter diehards, the safest option may be to double up, per one study from Virginia Tech, which found that doing so may be as effective as a cloth mask.
Bandanas and face shields are not recommended
One of the crucial elements of a face-covering, according to experts, is containing one’s own respiratory droplets. A bandana, which is typically open at the bottom, is likely unable to do this. On top of this, the face coverings are typically made of material that is unable to contain large droplets. It’s for this reason that they are listed as a “last resort” by the CDC, only to be used when nothing else is available.
Face shields, which are typically made of plastic, offer more protection than bandanas, protecting an individuals eyes, which can be a route of transmission. But the CDC says that “there is currently not enough evidence to support the effectiveness of face shields for source control.” For this reason, the organization does not recommend wearing one unless an individual, for medical reasons, cannot wear a face mask.
N95s are not recommended for use by the general public
There’s a reason that fitted N95 masks were already commonplace among healthcare workers, and that’s because they provide the ultimate protection from respiratory droplets. Although it may be tempting for those who are extremely concerned about the virus, the Food and Drug Administration cautions against laypeople searching for them.
“The Centers for Disease Control and Prevention (CDC) does not recommend that the general public wear N95 respirators to protect themselves from respiratory diseases, including coronavirus (COVID-19),” the FDA writes. “Those are critical supplies that must continue to be reserved for health care workers and other medical first responders, as recommended by current CDC guidance.”
For the latest coronavirus news and updates, follow along at https://news.yahoo.com/coronavirus. According to experts, people over 60 and those who are immunocompromised continue to be the most at risk. If you have questions, please reference the CDC’s and WHO’s resource guides.
