As the U.S. has continued to reopen amid a deadly pandemic, masks have offered many people what feels like a simple way to responsibly return to something resembling normalcy. Multiple studies have found a correlation between early, widespread mask use and a lower COVID-19 death rate, part of what led a shift in emphasis from social distancing to covering up. In July, CDC director Robert Redfield said at a press conference that “if all of us would put on a face covering now for the next four weeks, six weeks, we could drive this epidemic to the ground.” While the suggestion could be seen as an improvement over President Trump’s own pronunciations, it also portrayed masks as a one-stop solution to COVID-19, rather than what Osterholm and others believes they should be: one part of a broader action plan that should include social distancing and avoiding prolonged indoor contact.Versions of Redfield’s train of thought have become commonplace on the internet. One recent meme that’s floated around depicts two people, one of whom is a “COVID-19 carrier,” the other is a “contagion risk.” The contagion risk goes from high to low based on who is wearing the mask. The risk is highest when only the “contagion risk” is wearing a mask and lowest when both people are. The oversimplified graphic doesn’t say what type of mask is being used, the length of time the two were in contact, or if they’re indoors or outdoors—all factors when talking about aerosolized transmission.“I seem to be somewhere in the middle on this issue, but somehow that’s considered an extreme position.”
Scientific research can and often does deliver nuanced and even conflicting information, especially when dealing with a novel virus. That scientific reality clashes with attitudes in an increasingly polarized country. The problem has become particularly burdensome to scientists working in real time to address the ongoing public health crisis. Questions like which masks work, and how well they do, will remain critical in best protecting the American population.In early April, Osterholm consulted with infectious disease experts at the National Academies of Sciences, Engineering, and Medicine as they prepared a “rapid expert consultation” on “the effectiveness of homemade fabric masks worn by the general public to protect others.” They reviewed filtration studies from a span of 12 years and found that there wasn’t enough evidence on aerosols and cloth face coverings to say conclusively one way or the other, acknowledging that efficacy would likely depend on “how the masks are made and used.”“If two people are talking in a room, both wearing masks made from T-shirts, and one of those people has the virus, the other is very likely to get sick if they stay in the room long enough.”
Fleece, scarves, and bandanas, for example, are not great at trapping aerosols. Masks made entirely out of cotton T-shirts are better, but not as effective as several layers of 100 percent cotton and silk . Better yet are layers of 100 percent cotton, silk, and spunbound polypropylene. Fit is also crucially important: If there are gaps around the sides of your masks, aerosols are going to find their way in and out no matter the material.“This isn’t a pro-mask, anti-mask discussion,” Osterholm said. “This is about what the science tells us about the efficacy of cloth face coverings, and how much of a role they play in slowing transmission.”In July, 239 scientists from around the world signed an open letter to the World Health Organization (WHO), writing that it was "time to address airborne transmission of COVID-19." Early in the pandemic, WHO said that the virus was primarily transmitted through droplets, the relatively large particles that are emitted when people cough or sneeze and quickly fall to the ground. Back then, cloth masks of any sort started to seem like an effective tool, since they could successfully block such droplets. But aerosols are a smaller kind of particle—one that is emitted when we cough and sneeze, but also when we breathe, talk, or sing. Because of their small size, aerosols can stay in the air much longer, allowing them to travel further and potentially more easily slip through someone else’s mask. If it’s both aerosols and droplets that are transmitting the virus, then the calculus on masks might need to shift.“This isn’t a pro-mask, anti-mask discussion.”
Even the experts who are more skeptical of masks’ efficacy say people should wear one, so long as it’s not at the expense of other practices, like social distancing. Any tool that provides even the possibility of slowing transmission should arguably be utilized by as many people as possible. Osterholm and Lisa Brosseau, his colleague at CIDRAP and an expert on respiratory protection and infectious diseases, said they’d agree with that, up to a point.Because virulent anti-maskers have so politicized the issues—throwing dramatic fits in grocery stores and screaming at strangers—even suggesting the potential limitations of cloth masks can come across as denialism.
Since that time, the issues surrounding masks have extended out from the scientific realm and into the political world. That politicization, pushed by politicians and conspiracy theorists, on the right, has led to a lack of patience for nuance more broadly. Osterholm said he has since been told by friends in the media that they won’t have him on their shows because he comes off as too “anti-mask.” In a July profile of Osterholm in Mpls. St.Paul Magazine, the author wrote, “I realized Osterholm was no longer America’s midwest voice of reason when more than one friend synthesized his message as that of ‘the anti-mask guy.’”“If you don’t want to get pregnant, the most effective way to prevent it is staying home by yourself. Masks are prophylactic. They’re not universally 100 percent effective.”
In stories about the salon, however, very little was mentioned about the stylist who became infected. The headline of The Washington Post story read “The outbreak that didn’t happen: Masks credited with preventing coronavirus spread inside Missouri hair salon.” Brosseau worries that these kinds of stories are being used to push workers back to unsafe environments, and that it’s important to highlight the difference between what happened with the clients and stylists. “I’m worried we're turning a knife in the back of workers,” she said.In the media, the focus on masks has often eclipsed other, more significant factors in COVID-19 transmission, like whether someone has recently attended a large, indoor event. After Herman Cain died last month from COVID-19, which many suspected he contracted at a Trump rally in Tulsa, Oklahoma, the New York Times asked, “Will Herman Cain’s Death Change Republican Views on the Virus and Masks?” Dozens of other headlines about Cain’s death mentioned his anti-mask stance too. The stories seemed to suggest that the major risk factor was the lack of masks at the event, rather than the fact that he had sat in an enclosed space with 6,000 people talking and cheering for at least two hours.“If you don’t want to get pregnant, the most effective way to prevent it is staying home by yourself,” Santarpia said. “Masks are prophylactic. They’re not universally 100 percent effective.” For rally attendees, the risk may have been heightened by lack of masks, but a lack of masks didn’t create the risk.Prior to the Tulsa rally, as cases in the Oklahoma area were spiking, MSNBC’s Brian Williams asked Osterholm if the event was “public health malpractice.” After months of watching his words get misrepresented, he worried that anything he said about a Trump rally would be contorted and politicized. Osterholm offered a theoretical answer instead.“If all four Beatles were able to be back tonight in a large indoor area concert in a place like Tulsa, I wouldn’t go. I wouldn't want any of my loved ones to go,” he replied. “That's how we have to understand this situation.”“I’m worried we're turning a knife in the back of workers.”