Cloth masks are useless in fight against Omicron, expert warns

CNN’s medical analyst Dr Leana Wen has said that cloth masks are useless in the fight against the spread of the Omicron variant of Covid-19, instead encouraging viewers to wear three-layer medical masks.

Speaking on Monday, Dr Wen said that New York City Mayor Bill de Blasio shouldn’t cancel the New Year’s Eve ball drop in Times Square, noting that the event requires proof of vaccination and is being held outdoors.

“We should be keeping the events that are safe and also the events that have fun for people too. We can’t be cancelling everything, especially if we’re going to be living with Covid for the foreseeable future,” she added.

“I would say that if you choose to go, make sure that you’re vaccinated and boosted, make sure that you’re wearing a mask, even though it’s outdoors, if there are lots of people packed around you, wear a three-ply surgical mask,” Dr Wen said. “Don’t wear a cloth mask.”

“Cloth masks are little more than facial decorations. There’s no place for them in light of Omicron. And so wear a high-quality mask, at least a three-ply surgical mask,” she added.

The George Washington University professor also urged viewers who plan on visiting elderly relatives or immunocompromised people after the event to “wait three days, get tested, and then see those vulnerable” people.

Later on Monday, Dr Wen added to her remarks on Twitter, writing that “my point isn’t that we don’t need masks, but rather that we should require masks that are most effective to prevent disease transmission. Everyone, including children, should be wearing at least a three-ply surgical mask when indoors and around others of unknown vaccination status”.

An infectious disease fellow at Stanford University, Ashley Styczynski, told Bloomberg in October that “there are very few real-world studies examining the impact of cloth face coverings”.

“Various laboratories have measured the filtration efficiency of different cloth materials used in masks. Cloth materials typically block 10-30 per cent of aerosol-sized particles that contribute to [the] airborne spread of SARS-CoV-2,” she added.

Lab studies have shown that surgical masks, such as N95’s, block around 95 per cent of aerosol-sized particles.

Dr Sunil Joshi, the president of the Duval County Medical Society Foundation, told WJXT: “Most of the studies where they are looking at the spread of viruses are done with N95, K95 masks so we have better data with those opposed to the cloth masks.”

“The cloth masks may or may not always be well-fitting, so there is always that potential concern. It’s hard to know exactly how much but it’s certainly something where the data supports wearing a KN95 mask,” he added.