Passengers board trains at a Beijing railway station before the Lunar New Year, on January 23, 2020.Kevin Frayer / Getty

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Wendover Brown runs a boutique business in San Francisco selling hand-sewn face masks. Her patterned products are called Vogmasks (pronounced “vogue masks”). They are meant to look more like clothing than medical devices—cosmetically palatable respirators for people trying to avoid air pollution or allergens. Most months, Brown says, she sells a few thousand.

Last week she was shocked to get an order from Dubai for 100,000. That was one of several enormous requests from around the world, amid concerns about the new coronavirus.

Cheaper, standard surgical masks—the expandable rectangles of paper—are reportedly in short supply in many places, as are N95 respirators used in health-care settings—the cup-shaped devices that seal tightly to the face with elastic bands. (N95 is the designation used by the U.S. National Institute for Occupational Safety and Health, indicating that a mask can block inhalation of 95 percent of airborne particles.) Even though Vogmasks carry no such formal certification, boutique suppliers like Brown are selling out as people grasp for longer-term, business-casual mask options.

Brown had to turn down those huge orders. “This isn’t what we do,” she says. “I have no ability to fill that kind of order.”

Nor were her masks designed to protect people from coronaviruses. Brown tells me she’s been emailing with a virologist in the hope of getting expert advice on what—if anything—she can tell people about their effectiveness against transmission of the new outbreak. But he responds with long answers about how it depends on the properties of any given virus, and how much a contagious person is secreting, and how closely the person comes into contact with others. Essentially, no masks are perfect, and their value always depends on the context in which they’re used. In moments of fear, even a small chance of protection can become extremely valuable to people who feel they have few other actions to take.

This may be why some people in the U.S.—still at very low risk of contracting the new coronavirus—have newly begun wearing masks. Americans are now diving into and depleting global stock that could be needed elsewhere, in order to don masks as they go about their daily life. In the past few days I’ve noticed growing numbers on the streets of Boston and New York and New Haven, and on the T and subway and Amtrak in between, despite a lack of any new recommendation for their use.

Masks have been strongly suggested and even temporarily made mandatory in some places by the Chinese government, but no U.S. authority has done the same. Saad Omer, an infectious-disease epidemiologist and the director of the Yale Institute for Global Health, says that it can’t hurt if healthy people simply choose to wear masks in the U.S., but if there’s a benefit at this point it’s likely psychological: “People want to feel empowered; there’s nothing worse than a lack of feeling of self-efficacy.”

At the same time, any unfounded sense of protection or immunity carries at least some possibility of detracting from effective preventive measures. As the U.S. Centers for Disease Control and Prevention recommends: Wash your hands often, with soap and water, for at least 20 seconds, or use an alcohol-based hand sanitizer. Disinfect frequently touched surfaces. Don’t carry around used tissues, even if they still have some usable real estate. Stay home as much as possible when in the pathogen-spewing phase of any respiratory disease—be it coronavirus, influenza, or other. Bringing a contagious disease to work or onto the subway poses a hazard to others that can’t be totally eliminated with a mask. And, maybe the most difficult recommendation: Avoid touching your eyes, nose, and mouth. Most of us touch our faces several times every hour, mindlessly, and this is often how we catch viral illnesses. Despite never being especially close to anyone sick, we self-infect by rubbing our nose or eye after touching a mucus-misted surface.

The physical barrier of an elective face mask could help protect us from ourselves, by minimizing inadvertent face touching. But most of the value of masks is in situations where they are clearly necessary, even crucial. And in times of shortage, proper and judicious use becomes especially worth considering. In a café yesterday, I sat next to a man wearing a surgical mask and coughing beneath it. But his commitment to the cause seemed low; the mask wasn’t covering his nose. The value of a mask worn incorrectly can plummet to nearly zero. This point was made clear by a widely shared video last week, in which Wing Hong Seto, an infectious-disease specialist at Hong Kong University, demonstrated proper technique. “It works; we’ve done many studies,” he says, but emphasizes that fitting the mask tightly around one’s nose is crucial. (I debated the social value of correcting the man in the café, but did not.)

When Seto says the surgical mask “works,” he is referring especially to the way medical-grade masks have an absorbent lining to trap what we cough or sneeze up. Hypothetically, any physical barrier will help minimize the amount of particulate matter one spews into the air, but a mask worn inside out or loosely tied loses much of its effect. As for the degree to which surgical masks worn by healthy people help prevent the inhalation of a respiratory virus, the evidence is less clear. The CDC offers no certification to attest to exactly how much airborne matter is blocked by such masks, unlike N95 respirators. But a 2019 study in JAMA did find that doctors who wore surgical masks seemed to get the flu at no higher rates than those who wore N95s.

The real importance of the run on masks at this moment may be that it is emblematic of broader, uncomfortable truths about outbreak preparedness. Supplies of many basic medical products like masks and respirators rely on international trade, which becomes unpredictable during emergency scenarios. Imports could be cut off during a pandemic, either by border shutdowns or rising demand within a country. In the U.S., for example, only 5 percent of surgical masks purchased annually are made here.

State health departments do recommend that hospitals keep an emergency store of respirators, but only enough for very short periods. The New York Department of Health advises hospitals to keep “at least a three-day supply of N95 masks readily available for use in a variety of emergency situations.” This assumes that more will be available for purchase. But there’s no guarantee that will be true: During the 2009 flu outbreak, hospitals ran low on masks. The CDC keeps a national stockpile for emergencies, but its latest reported numbers are lower than other countries’. The 2009 flu used up more than 75 percent of the stockpile.

Brown says that one of the people trying to place a bulk order with her was a buyer for a medical-device supplier, which alarmed her. “The boutique sector is totally unequipped to meet the needs of the population in an emergency,” she says. And crucial questions of efficacy remain. The evidence that most masks now common in China can even meaningfully filter out air pollution, let alone viruses, is inconclusive, according to Wong Chit Ming at the University of Hong Kong School of Public Health. In the U.S., testing of the efficacy of individual mask brands is up to individual manufacturers—both to conduct and to share their results. Brown does this for Vogmasks, but the CDC doesn’t recognize such products as medical equipment, and so consumers don’t have a standardized system of certification to show which masks might be useful and which are glorified cheesecloth.

Brown is quick to say that the face-mask market is full of cheap products of unknown benefit. And even if boutique products like hers did clearly help prevent disease, her supplier is in South Korea—which is experiencing its own shortage of surgical masks. In the event of a pandemic that saw borders shut down, supplies of all sorts of masks could be expected to dwindle. Taiwan has already halted exports and is reportedly inspecting people at borders to ensure that no one is smuggling N95 or surgical masks out of the country.

This threat of shortages of basic medical tools extends well beyond masks. In a serious pandemic, the U.S. is not prepared to be isolated for long. Many of the CDC guidelines for use of respirators involve rationing and judicious use, even in hospitals. Supplies more potentially vital than masks, including antibiotics, antivirals, and saline, are also mostly produced internationally. Even many of the vitamins that fortify our highly processed, white-bread diets come from China. This level of dependence is not generally considered a matter of national security, but some believe it should be.

Among the proposed solutions is the idea that hospitals could be required to purchase vital medical devices and drugs from companies based in the U.S. (and whose supply chains could endure a global shutdown). Another is that a supply of products necessary for survival could, like the public water system, be managed in a centralized way—with government agencies even manufacturing these essential products.

Both of those options would substantively alter the state of global commerce, and might be feasible for only a handful of wealthier countries. Many places simply don’t have the resources or capacity to be self-sufficient, nor would such redundancy of production lines make sense. Given these realities, the pertinence of an orchestrated international response in times of health crisis becomes only more clear. The global medical community has the capacity to address extremely dangerous outbreaks. In isolation, most countries do not.

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