Is it time to wear 2 masks? Here’s what local experts and the Centers for Disease Control and Prevention are saying
photo by: AP Photo/Rogelio V. Solis
Amid concerns regarding new strains of COVID-19 spreading across the United States, the Centers for Disease Control and Prevention released additional guidance and a new report on Wednesday about best practices for wearing masks.
According to the report, experiments conducted by the CDC showed that exposure to potentially infectious aerosols decreased by about 95% when two mannequins both wore tightly fitted masks — either through knotting and tucking a medical procedure mask or by layering a cloth mask over a medical procedure mask, also known as “double masking.”
Dr. Thomas Marcellino, Douglas County’s health officer, said strategies such as double masking have increasingly been on people’s minds.
“I think that what happened is we see these variants and we see the spread is easier, and so we start to think, ‘How can we deal with these? … We can do better with masks,'” Marcellino said in a phone interview with the Journal-World on Wednesday.
The Journal-World spoke to Marcellino and Dr. Jennifer Schrimsher, an infectious disease physician at LMH Health, individually about the strategy of double masking. The two doctors agreed that while two masks — if worn correctly — would likely increase protection, the more pressing issue was getting the general public to wear one mask correctly.
“If you put up two fences or two layers of chicken fence, it’s more likely to be effective than one layer of chicken fence. But if you’re just trying to keep out chickens, you only need one layer,” Schrimsher said.
Marcellino said the current recommendation at Lawrence-Douglas County Public Health was that masks should have at least two layers, completely cover one’s nose and mouth and fit snugly on one’s nose and the side of the face. He said more layers would likely provide better protection from inhaled particles.
“It’s about finding a balance, really, about how can you breathe and function and still have protection against any contaminant or virus,” he said.
Schrimsher also said it was important for masks to be easy to breathe through. If a mask has too many layers and is difficult to breathe through, then people will likely suck air in from the sides of the mask, which will defeat the purpose of wearing one, she said.
“One mask with a couple layers is probably going to be more beneficial for the wearer than trying to stack a bunch of masks and not being able to breathe,” she said. “If we could get people to wear one mask appropriately, we’d be in a lot better place.”
Of course, if someone wants to wear two masks, that will provide extra protection as long as the masks fit correctly, Marcellino said. People who are at high risk from the virus might choose to double mask, as long as they are able to function safely and breathe well.
The two strategies employed in the CDC’s recent study — double masking and knotting and tucking the ear loops of a medical procedure mask — were both intended to create a tighter fit that provided more protection. The double masking strategy that the CDC experiments used specifically involved wearing a disposable mask underneath a cloth mask. The CDC’s experiments did not include other combinations of masks, such as cloth over cloth, medical procedure mask over medical procedure mask or medical procedure mask over cloth.
photo by: Centers for Disease Control and Prevention
But the CDC’s updated mask guidance says people should not wear two disposable masks or combine a KN95 mask with any other type of mask. The disposable medical procedure masks are not designed to fit tightly, the guidance says, so wearing more than one will not improve the fit.
The CDC did not offer an explanation for why people should not combine a KN95 mask with another type of mask, and it did not respond to a question from the Journal-World asking why. According to the CDC’s website, a KN95 mask is a type of filtering face mask that is often made in China and is similar to the N95 masks commonly used in the United States.
Marcellino and Schrimsher said N95 masks filter well on their own and that wearing a second mask under an N95 mask would worsen the seal of an N95 mask. But Marcellino also said that when he wears an N95 mask, he typically wears another mask over it to protect it from becoming soiled.
For instructions on how to knot and tuck the ear loops of a medical procedure mask in order to improve the fit, the CDC linked to a YouTube video by UNC Health titled “Pro Tip to help your Earloop Mask Fit More Tightly.”
Marcellino said he thought the renewed attention on masks and their effectiveness had been brought on by newly detected variants of COVID-19. Schrimsher said that the variant from the United Kingdom, which is more transmissible, would likely be the predominant strain in the United States by the end of March. She also said there seemed to be a lull in reported COVID-19 cases at the moment.
“It feels like the calm before the storm again,” she said.
Should new COVID-19 variants send the number of cases in Douglas County in the wrong direction, and should the hospital become overwhelmed, Marcellino said the health department might need to recommend double masking.
“Right now, there’s no evidence that it’s widely distributed,” Marcellino said of the COVID-19 variant from the United Kingdom. The variant was identified in Kansas on Feb. 3.
“It has the potential to become more prominent, and that’s what we are trying to avoid. That’s why mask usage is important, because we have to assume that it could be here,” Marcellino said.
More information from the CDC about how to make one’s mask fit better:
The CDC’s updated mask guidance includes additional information about how to improve a mask’s fit in order to receive better protection.
The CDC lists two important ways to make sure a mask fits properly. First, make sure it fits snugly on your face, and that there are not gaps around the nose, side or neck that could let air with respiratory droplets leak in and out around the edges. Second, pick a mask with multiple layers in order to keep your own respiratory droplets in and others’ droplets out.
Here are other tips from the CDC:
• Choose a mask with a nose wire.
• Use a mask fitter or brace.
• If your cloth mask doesn’t have multiple layers, you can add another layer of protection by wearing a disposable mask underneath the cloth mask.
• Knot and tuck the ear loops of a medical mask.