Harvard’s Joseph Allen says ‘everyone’ should be wearing an N95 mask

“This could be the key to slowing the pandemic and limiting spread from the new more highly transmissible variants until we all get vaccinated.”

FILE -- An N95 mask hangs from the rearview mirror of a car in Brooklyn on April 7, 2020. Hospital contracts for N95 masks created problems in the supply chain. (Demetrius Freeman/The New York Times) Demetrius Freeman / The New York Times, File

The call for the federal government to make sure high-filtration masks are available for all essential workers and the general public is growing.

Joseph Allen, an associate professor and the director of the Healthy Buildings program at the Harvard T.H. Chan School of Public Health, penned an op-ed for The Washington Post on Tuesday, laying out the case for why “everyone” should be wearing an N95 mask at this point in the COVID-19 pandemic.

Allen isn’t the only local public health expert pushing for “better masks” as the pandemic continues. His colleagues at Harvard Medical School, Dr. Abraar Karan and Dr. Ranu Dhillon, are pressing for a national initiative that would distribute high-filtration masks, such as N95s, to every household in the United States.


“I’m not alone in calling for better masks, and certainly not the first,” Allen wrote. “But I am joining the chorus calling for them. This could be the key to slowing the pandemic and limiting spread from the new more highly transmissible variants until we all get vaccinated.”

While a typical cloth mask is expected to capture about half of the respiratory aerosols released when a person talks or just breathes, high-filtration masks like N95s filter 95 percent, Allen wrote. Two people wearing N95s results in a 99 percent reduction in potential exposure.

“In the scrambling for information and tools in early days of the pandemic, it was acceptable to just say any cloth mask will do because it’s true,” Allen wrote. “Any face covering is better than none. But we’ve learned so much since then, and we need to adjust our strategy.”

The professor said there’s no reason at this point in the pandemic why any essential worker — or anyone else — should be without better masks.

Before the pandemic, N95s cost about 50 cents and were easy to manufacture, according to Allen.

“We could reduce exposure by 99 percent for what should be $1 a mask,” he wrote. “(Prices are higher now because of the failure to produce an adequate supply.) Throw in better ventilation and some distance between people, and you have hospital-grade protections.”


According to Dr. Nahid Bhadelia, an infectious disease physician and the medical director of the Special Pathogens Unit at Boston Medical Center, not only does the United States need a national effort to get hi-fi masks to the public, the government should start with releasing a standard for the masks that are available.

“It’s unconscionable that we have the largest use of PPE by American public in history and the quality of these masks is not being moderated, standardized or regulated,” she wrote on Twitter. “It’s not just about N95s. Those may not work in every situation but there are other qualities to good masks aside from filtration efficiency including fit and seal, ability to withstand moisture (from sweat and saliva) etc. These qualities could be improved in consumer masks.”

What is needed is the equivalent of Operation Warp Speed, the government initiative started under the Trump administration aimed at accelerating development, production, and distribution of COVID-19 vaccines, for “high quality cheap PPE and improved ventilation in public places,” she said.

“Do not get me wrong — a mask is better than no mask,” she wrote. “Wear a mask. Using [the] excuse of no high quality masks to not wear a mask is like refusing a rescue raft because you weren’t given a boat at the time.”


During a Wednesday night town hall on CNN, Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases and a top medical adviser to President Joe Biden on COVID-19, and Dr. Rochelle Walensky, the new head of the Centers for Disease Control and Prevention and the former infectious disease chief for Massachusetts General Hospital, were asked about the push for better masks. Both doctors said the general public doesn’t need to wear N95 masks.

Boston doctors Karan and Dhillon, who have been vocal advocates for a hi-fi mask program, expressed frustration on social media about the response from Fauci and Walensky.

“We need to do everything we can [to] stop transmission to save lives now, prevent the emergence and spread of faster-spreading deadlier variants and time to get vaccination up to scale,” Dhillon wrote in a Twitter thread rebutting the argument from the top officials.

Karan reiterated in his own thread that the argument for providing better masks isn’t as simple as “mass producing N95s.”

“You still need to make sure the fit is correct and that people are using them consistently during high transmission risk situations both outside AND sometimes inside the house,” he wrote.

Until there is federal leadership for expanding access to the high-filtration masks and better guidance for their use, Allen wrote in his op-ed that if you can’t find a better mask to “double-mask” using a surgical mask and a cloth mask.

“The surgical mask gives you good, certified filtration, while the cloth mask on top helps improve the fit,” he wrote. “Research shows this can achieve greater than 90 percent filtration.”



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