CDC revises guidance, suggests double-masking or more snug single mask

WASHINGTON (SBG) — The Centers for Disease Control and Prevention updated its guidance on mask use Wednesday after new research concluded wearing two masks or modifying a single mask to fit more snugly could greatly reduce transmission of COVID-19, but convincing a weary public to adhere to that guidance might not be easy.

A study published in the CDC’s Morbidity and Mortality Weekly Report found placing a cloth mask over a medical procedure mask decreased exposure to aerosol particles that spread the coronavirus by up to 95%. A single surgical mask or cloth mask alone blocked less than 45% of particles from a simulated cough.

Researchers also found wearing a single medical procedure mask with the ear loops knotted and the sides tucked in could drastically reduce exposure. Using a “mask fitter” or placing a nylon covering over a mask can be more effective than just wearing a regular cloth or surgical mask on its own, as well.

“Until vaccine-induced population immunity is achieved, universal masking is a highly effective means to slow the spread of SARS-CoV-2 when combined with other protective measures, such as physical distancing, avoiding crowds and poorly ventilated indoor spaces, and good hand hygiene,” the report stated. “Innovative efforts to improve the fit of cloth and medical procedure masks to enhance their performance merit attention.”

The authors of the report emphasized that its findings were limited in scope. They specifically tested a three-ply cloth mask over a surgical mask, and they did not examine other types of masks or combinations of those two masks, such as putting the cloth mask over the surgical mask or wearing two of the same kind of mask.

There are also potential complications involved with doubling-up masks for some users, like impeding breathing or peripheral vision. Still, CDC officials say either wearing two masks or knotting and tucking a single mask could significantly reduce the effects of the pandemic on public health and the economy.

“We need to up our game to slow the spread of the virus and slow its evolution,” Dr. John Brooks, the CDC’s chief medical officer for coronavirus response and lead author of the report, told The New York Times.

The new guidance comes 10 months after the CDC first recommended Americans wear cloth or fabric face coverings in public, and it follows the emergence in the U.S. of highly transmissible variants of the coronavirus first identified in United Kingdom, South Africa and Brazil. Officials acknowledged the possibility that the new data could be greeted by fatigue or skepticism from the public.

“I know some of you are both tired of hearing about masks, as well as tired of wearing them,” CDC Director Dr. Rochelle Walensky said at a press briefing Wednesday. “Masks can be cumbersome. They can be inconvenient. And I also know that many of you still have questions about masks.”

The guidance does not alter recommendations for who should wear masks or when to wear them, but it does offer several suggestions for improving mask fit. Walensky noted a recent survey found half of adults who wear masks regularly wear them incorrectly, stressing the importance of ensuring the mask fits closely and snugly over the nose and mouth.

“The bottom line is this,” she said. “Masks work, and they work best when they have a good fit and are worn correctly.”

The CDC is still not recommending civilians use N95 respirators, which can block at least 90% of airborne particles. Supplies of those devices are still limited, and the latest data suggests a well-fitting cloth mask combined with a surgical mask can provide similar levels of protection.

Initial reactions to the new report have been mixed. Some scientists have been talking about wearing a second mask to increase protection for months, but others are not yet prepared to embrace the recommendations without further study.

Neysa Ernst, a nurse manager in the Department of Medicine at Johns Hopkins Hospital, said she is not changing her guidance to wear a single quality mask in public that covers the mouth and nose. She did not question the CDC’s findings, but she warned a second mask might not necessarily be more protective in practice than one mask worn properly.

“It’s more complicated than that... Anecdotally, what I have seen with double-masking is it causes people to be less vigilant with their social distancing,” Ernst said, adding that a second mask can also make the wearer uncomfortable and lead them to take off both masks.

Many people do not wear masks properly, though, and Dr. Perry Halkitis, dean of the Rutgers School of Public Health, indicated the new CDC guidance could be an attempt to address that problem. The second mask can help prevent air from leaking around the edges of the inner mask and place additional layers of fabric in the path of infectious particles.

“We come around to this idea, well, if we really encourage people to wear two masks, maybe then it will somehow prevent the incorrect behavior and create another shield in light of these very transmittable new variants,” Halkitis said.

Some federal officials have been promoting the virtues of double-masking for weeks, but the recommendation does not appear to have permeated with the general public so far. A YouGov survey conducted in late January found 61% of Americans had never worn two masks layered on top of each other, and only 15% did so frequently.

"If you have a physical covering with one layer, you put another layer on, it just makes common sense that it likely would be more effective," Dr. Anthony Fauci, the federal government’s top infectious disease expert, said on Jan. 25.

Another study published last summer found double-masking can be nearly twice as effective as a single mask in filtering out aerosols. That research also found a wide range of efficacy of different cloth masks, ranging from blocking 28% of particles to 91%.

President Joe Biden has regularly worn two masks in public since December, and several prominent figures double-masked at Biden’s inauguration last month, including youth poet laureate Amanda Gorman. Some opponents of coronavirus restrictions have been dismissive of the practice, though.

Despite overwhelming scientific consensus that masks are effective in preventing the spread of the coronavirus, they have been a sensitive and divisive issue since the start of the pandemic. Federal health officials initially advised the general public against wearing masks amid concerns about potential shortages of supplies for frontline workers and hospital staff.

That guidance quickly changed as epidemiologists learned more about how the virus is transmitted and officials and experts advised the public to wear cloth or surgical masks. However, then-President Donald Trump frequently voiced skepticism about face coverings and rarely wore one in public.

The result was a deep partisan disparity in reliance on masks, as many Democrat-run cities and states embraced mask mandates but some Republican governors resisted. Biden made widespread mask use a central plank of his coronavirus response strategy, while Trump’s messaging on the issue was inconsistent even after he contracted the virus himself.

“Unfortunately, the seeds of distrust were sown a year ago. Over the course of 10 months, many political leaders and pundits told the public not to trust their own eyes,” said Peter Loge, director of the Project on Ethics in Political Communication at George Washington University. “That trust is hard to earn back.”

At this point, 36 states require masks in at least some public settings, as well as Puerto Rico and the District of Columbia. On his first day in office, President Biden signed executive orders mandating masks on federal property and while traveling.

Recent polls show most Americans support mask use, but some political differences remain. A December HealthDay/Harris Poll showed 71% of Democrats regularly wear masks when they leave home, compared to 61% of Republicans.

In a December Kaiser Family Foundation poll, 73% of Americans said they wear masks every time they leave home, but Democrats were 30 percentage points more likely to do so than Republicans. Most of the 11% of respondents who said they rarely or never wear masks were white, male, and Republican.

A survey released last month by the University of Southern California's Dornsife Center for Economic and Social Research found 83% of Americans believe masks are effective, but only 51% regularly wear them when in close contact with people outside of their household. However, 90% did say they wore masks when grocery shopping.

All of this means persuading Americans to start wearing a second mask or change how they wear masks now could pose challenges. Halkitis suggested public messaging should focus on an admission that vaccination is not progressing fast enough and a need to do more to protect against the more infectious strains of the virus until vaccines are widely available.

“A year into this pandemic, where we started with, ‘You don’t need a mask,’ to, ‘You need a mask,’ to, ‘You need two masks,’ we’re going to have a very difficult time for most people to adopt this two-mask behavior,” Halkitis said.

According to Loge, a former Food and Drug Administration communications adviser, honesty and consistency about the pandemic is vital to building public confidence in the response. Underplaying or overhyping risks can have damaging consequences, and there have been instances of both over the last year.

“The best public health communication treats people like adults,” Loge said. “If public health leaders are honest about what they know, what they don't know, and what we should do, then we will listen.”

With vaccine distribution accelerating and variants of the coronavirus spreading, the end of the pandemic may be on the horizon, but the path to get there could still prove perilous. Loge underscored the importance of communicating both of those points to the public if officials want them to comply with additional mitigation measures.

“With a last, focused push, we can contain the pandemic and unleash the economy,” he said. “If we celebrate too soon, we'll only set ourselves up for failure.”

Regardless of the messaging strategy, the concept of double-masking could still be a hard sell when many Americans reject wearing one mask. Some experts say other aspects of the new CDC guidance related to improving the performance of a single mask might be easier to follow and would also carry substantial public health benefits.

“I’ll take one mask over no mask,” Halkitis said. “I would prefer two masks, but... one mask worn correctly is better than zero.”