Masks and Omicron variant: Are cloth masks still effective? Should you double mask? Experts weigh in.

A woman wearing a protective face mask walks past decorated Christmas trees at 'Place Vendome' during the coronavirus (COVID-19) epidemic on December 16, 2021 in Paris, France.
The Omicron variant has been detected in 37 states less than three weeks after being named a variant of concern by the WHO (Photo: Chesnot/Getty Images)

The Omicron variant has been detected in 37 U.S. states, less than three weeks after the World Health Organization (WHO) named it a variant of concern.

The WHO warned that this variant, also known as B.1.1.529, has coincided with a "steep" rise in COVID-19 infections in South Africa, where it was first detected. "This variant has a large number of mutations, some of which are concerning," it said in a statement, before reminding people to follow known COVID-19 mitigation strategies like getting vaccinated against the virus, avoiding crowded spaces, trying to practice physical distancing and wearing well-fitting masks.

The Centers for Disease Control and Prevention (CDC) is also warning about Omicron, noting that "we don’t yet know how easily it spreads, the severity of illness it causes or how well available vaccines and medications work against it." While the CDC notes that vaccines "remain the best public health measure to protect people from COVID-19," the agency also points out that "masks offer protection against all variants," before urging people to wear them in public indoor areas where there is "substantial or high community transmission," regardless of your vaccination status.

It's been a year and a half since the American public was first encouraged to wear masks to protect against COVID-19, and since then mask mandates across the country have been spotty. Some businesses, including many doctor's offices, require you to wear them indoors, while mask mandates are forbidden in other places, like the state of Florida.

With the rise of Omicron, the continuing circulation of the infectious Delta variant and cases of COVID-19 continuing to rise across the country, it's only natural to have questions about masks as we move into the thick of the holiday season. Are cloth masks still up to snuff? Should we all be in N95 equivalents, like KF94s and KN95s? Here's what the experts say.

Your masks should meet certain criteria.

The CDC recommends that masks have the following:

  • Two or more layers of breathable material

  • Complete coverage of your nose and mouth

  • Fits snuggly against your face without gaps

  • Has a nose wire to prevent air from leaking out of the top of the mask

Another requirement that wasn't listed by the CDC? Comfort. "Can you wear the masks for a long period of time, which is typically how breathable it is, and is it a good design?" Aaron Collins, a mechanical engineer in Minnesota and self-described "citizen engineer" who has been studying mask efficiency, tells Yahoo Life. This is crucial to ensuring that your mask is actually worn, and worn correctly, he says.

Your cloth mask is still OK but not necessarily the best protection you can have.

"Cloth masks are indeed good if they are several layers and fit well," Dr. William Schaffner, an infectious disease specialist and professor at the Vanderbilt University School of Medicine, tells Yahoo Life. But, he points out, "we can't solely rely on them, just as we don't rely only on vaccines."

Still, Dr. Prathit Kulkarni, assistant professor of medicine in infectious diseases at Baylor College of Medicine, tells Yahoo Life that "there is some evidence that surgical face masks are potentially a bit better than cloth masks." A study that was just published in the journal Science analyzed data from 342,183 adults in Bangladesh and found that surgical masks were 95 percent effective at filtering out virus particles, compared with 37 percent for cloth face masks.

"Cloth masks are our 1918 pandemic technology, used 100 years ago," Collins says. "We have the technology — the high filtration, electrostatically charged, meltblown [masks like KF94s, KN95s and N95s] — and we should use it."

That doesn't mean cloth face masks don't have a role in protecting you. Dr. Thomas Russo, professor and chief of infectious disease at the University at Buffalo in New York, tells Yahoo Life that not all cloth face masks are created equal, and having features like a metal nose wire, three layers, and insertable filters will quickly ramp up protection. "I favor using the highest quality mask that fits well and you are comfortable wearing for a prolonged period of time," he says.

A surgical mask can be helpful — if you wear it correctly.

Again, a recent study found that surgical masks have the potential to provide great protection, but Kulkarni says the right fit is crucial with these. Your surgical mask should be "snugly fitting while not impeding breathing," he says.

"Surgical masks have the technology in them — the electrostatically charged meltblown — but they lack the fit," Collins says. "They are not designed to seal closely to the face." Surgical face masks aren't for everyone, he says, noting that they also have a "major annoyance" that they can "suck into your mouth, making it even harder to breathe" when you're doing things like climbing stairs or breathing hard.

There isn't really data to support double masking.

Double masking had a moment, but there hasn't been much information to suggest that this is necessary if you have a mask with multiple layers. "There is no strong data to support universal double masking at this point," Kulkarni says. "The key concept is that the mask should have a snug but still comfortable fit."

Collins calls double masking "the worst solution," adding, "if you can make it work, it is very hard to breathe in."

Have a stronger disposable mask handy for more crowded situations.

Think: at an airport, on a bus or in the mall. Collins is a big fan of using stronger filtration masks, like KF94s, the South Korean version of an N95 mask, and KN95s, the Chinese version of an N95 mask. (The CDC still recommends that N95 masks be reserved for health care workers.)

"At this point, KF94s, KN95s and N95s are a no-brainer," he says. "We have tons of them, they are very inexpensive now and provide way better protection than a surgical or cloth mask." Collins says his tests have found that these masks can be reworn for up to 40 hours in a "clean, office-type environment with very little reduction in filtration efficiency."

While Collins swears these masks are comfortable, not everyone agrees. "KN95, KF94 or N95 masks are indeed more protective than the conventional mask, but they're fitted much tighter if you wear them correctly and they do make breathing harder," Schaffner says. "Lots of people feel a bit claustrophobic in them. We generally don't recommend them because we're afraid they will discourage people from wearing masks."

But, if you feel comfortable using a KF94 or KN95, Russo says to go on ahead. "If not and a high-quality cloth mask — triple layer with a filter — works for you, that is fine," he says. "Even a less-than-optimal quality mask is better than no mask."

Overall, experts say the rules of good masking aren’t expected to change with Omicron, although the situation is still developing.

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