“The debate over whether Americans should wear face masks to control coronavirus transmission has been settled,” declares the New York Times‘ Knvul Sheikh. “Governments and businesses now require or at least recommend them in many public settings.”
Sheikh is right about the requirement or recommendation to wear masks in many public settings, but wrong about how the debate has been settled.
In truth, the masks do little or nothing to prevent the spread of the coronavirus, and actually cause real harm: by giving some people a false sense of security, thereby leading them to take fewer precautionary measures that actually do help stop or prevent the virus’s spread.
Social distancing, for instance, makes good public health sense. Yet, how many times have we seen people donned up in full mask-covering mode standing just inches away from a friend or colleague who is talking, gesticulating, or jointly texting on their phone?
I’ve seen this image many times. These people no doubt think they’re safe and doing the right thing because they are wearing a mask, but nothing could be further from the truth.
The mask, of course, does not protect the mask wearer. Instead, the mask theoretically protects other people from being the infected by the mask wearer if the mask wearer is an unknown or asymptomatic carrier of the coronavirus.
(A known or symptomatic carrier of the coronavirus would presumably be self-quarantined and not out and about in a public setting.)
I say theoretically because the logic or rationale behind the requirement to wear a mask depends on dubious assumptions that don’t stand up to practical, everyday scrutiny.
Makeshift Cloth Masks. First, the studies and analyses that say masks can prevent the spread of the coronavirus involve surgical masks. But most people aren’t wearing surgical masks. Instead, they’re wearing makeshift cloth masks, which are inherently subpar and leaky.
“Fabric masks also allow air in around the sides, but lack non-woven, moisture-repelling layers. They impede only about two percent of airflow in,” said May Chu, a clinical professor in epidemiology at the Colorado School of Public Health in an interview with LIveScience.
N95 surgical masks, reports Live Science, “effectively prevent viral spread [by filtering] out 95 percent of particles .03 microns or larger.”
However, because N95 surgical masks are in short supply, even for the medical professionals who most need them, and because they are difficult to properly wear or fit, the Centers for Disease Control and Prevention (CDC) “does not recommend them for general use.”
As for airflow outward through a mask, whether surgical or nonsurgical, studies report marginal benefits at best.
“The evidence for the efficacy of surgical or homemade masks is limited, and masks aren’t the most important protection against the coronavirus,” LiveScience notes.
“To me, it’s not harmful to wear these masks, but it doesn’t look from this study, [April 3, 2020, in the journal Nature Medicine], like there is a whole lot of benefit,” said Rachel Jones, an associative professor of family and preventative medicine at the University of Utah…
The recommendations that everyone wear masks are because “any kind of impediment is better than nothing,” Chu said. But fabric masks are not expected to be as protective as surgical masks, she said…
“There’s been enough research done to be able to confidently say that masks wouldn’t be able to stop the spread of infection, that they would only have a small effect on transmission,” added Ben Cowling, head of the Divison of Epidemiology and Biostatistics at the Hong Kong University.
“We shouldn’t be relying on masks to help us get back to normal.”
“Another April study, published in the Annals of Internal Medicine,” writes Mark Siegel, a clinical professor of medicine at NYU Langone Health, “revealed that the force of sick patients’ coughs propelled droplets through both surgical masks as well as cloth masks.”
The CDC,” Siegel explains,
based its revised mask recommendation on studies that found asymptomatic spread was far more common than had been thought. But there have been no studies on masks’ effectiveness in preventing it [emphasis added].
Although the coronavirus is highly contagious, it is much less so than, say, measles, which can linger in the air for two hours after a cough. a sneeze or even speech.
By contrast, the Covid-19 virus has not been proved to be aerosolized. Coronaviruses often enter the body through the eyes, and frequent hand and face washing and social distancing is much more effective than masks at preventing that.
Moreover, as Sheikh acknowledges:
“Many people also wear masks incorrectly, letting them dangle off the tips of their noses, or concealing just their mouths.
People also tend to readjust face masks frequently, or remove them to communicate with others, which increases their risk of being exposed or infecting others, he said.
He is Dr. Eli Perencevich, an infectious disease physician at the University of Iowa and the Iowa City Veterans Affairs Health Care System. Dr. Perencevich recognizes the problems inherent with masks, which is why, as Sheikh reports, he advocates the use of face shields instead.
Face shields, unlike masks,
protect the entire face, including the eyes, and prevent people from touching their faces or inadvertently exposing themselves to the coronavirus.
Face shields may be easier to wear than masks, he said, comparing them with wearing glasses or a hat. They wrap around a small portion of a person’s forehead rather than covering more than half their face with material that can create the urge to itch.
Importantly, face shields are far more sanitary than masks, which are supposed to be disposed of or regularly washed, but often aren’t. Indeed, mucus and germs can and do accumulate on the mask, thus putting the wearer at risk of other viral infections.
“The nice thing about face shields,” by contrast, “is that they can be resterilized and cleaned by the user, so they’re reusable indefinitely until some component breaks or cracks,” Dr. Yu said. A simple alcohol wipe or rinse with soap and hot water is all it takes for the shields to be contaminant-free again.
Dr. Yu, Sheikh notes, is a dermatology resident affiliated with Brigham and Women’s Hospital in Boston.
Siegel agrees: face shields make a lot more sense than masks. “When I worked on a coronavirus ward, I felt much safer because I also wore a plastic face shield, which blocks viral particles from even reaching the mask,” he writes.
Science Says. But my point here is not to argue for face shields instead of masks. My point is that people who (often self-righteously) insist we wear masks do so not because the science impels them to. They do so because it makes them feel good.
In truth, the science behind mask wearing is weak and lacking. The science behind social distancing, hand washing, and good hygienic practice, by contrast, is strong and compelling.
Which is why I avoid wearing a mask whenever I can while still practicing social distancing. The latter makes individual and public health sense; the former does not.
Feature photo credit: The Catholic Weekly.