Do Masks Protect Against Coronavirus? It Doesn't Mean Everyone Needs One
In the last few weeks, the coronavirus has become a global news story, with scientists and citizens alike scrambling to understand the details. As of Feb. 4, the virus has infected over 20,000 people globally, CNN reports, and has killed at least 426 people. And with at least 11 confirmed cases in the U.S., the Trump administration declared the coronavirus a public health emergency on Jan. 31. Now, countless people are using masks to try and protect themselves against coronavirus in the U.S. — even though it's not actually recommended.
Given the rising fears and media frenzy around the virus, people in countries like the United States have unnecessarily rushed to buy face masks. This has led to fears of a global shortage, as well as concerns that those who actually need masks won't be able to access them. Connie Steed, a South Carolina nurse and president of the Association for Professionals in Infection Control and Epidemiology, told Wired, “All over the country, our members are talking to their supply chain managers, who are calling in additional masks and respirators to make stockpiles." To complicate matters further, The Atlantic reports that only 5% of surgical masks purchased annually in the United States are actually made in the country. So in the case of an outbreak like this, there's a chance that supply will not be able to readily meet such mass demand.
To be clear, the Centers for Disease Control and Prevention (CDC) does not recommend that the "general public" wear a face mask as a means of preventing coronavirus. In fact, it actively recommends that you don't wear one. Instead, the federal agency suggests that people take the following precautions: Avoid close contact with sick people; stay home if you're sick; clean and disinfect surfaces that might be contaminated; and wash your hands with soap and water for at least 20 seconds frequently.
According to experts, a mask does help protect you from viruses that pass through respiratory droplets, but it won't guarantee your safety. "Everyday wear of a mask isn’t recommended [as a preventative measure], Dr. Janine Kelly, M.D., an attending physician at Maimonides Medical Center, explains to Bustle. "I only suggest wearing a mask if you’re being exposed to someone who might have been in contact with the virus."
Similarly, Nancy Messonnier, M.D., a director for the National Center for Immunization and Respiratory Diseases, said in a briefing in late January, “We don’t routinely recommend the use of face masks by the public to prevent respiratory illness. And we certainly are not recommending that at this time for this new virus.”
It's true that coronavirus can passed via respiratory droplets, which is why many people think masks are an easy solution. However, masks often don't fit extremely tightly around the skin, so small airborne particles can still get through.
If you do feel, for whatever reason, that your circumstances warrant wearing a mask, then two of the most common options to choose from are a surgical mask and an N95 respirator. N95 is a reference to the designation used by the U.S. National Institute for Occupational Safety and Health, which confirms that the mask can prevent the inhalation of at least 95% of airborne particles. As for surgical masks, the CDC reports that they're able to prevent "large" respiratory droplets from inhalation, but can't necessarily filter out smaller droplets.
There's varying research, regarding a potential difference in efficacy between the two options. For example, one clinical trial conducted by scientists from UT Southwestern Medical Center and carried out at 137 outpatient sites in seven U.S. cities from 2011-2015 found no "significant difference" between the two masks, in terms of how well they prevented influenza.
In contrast, a 2013 study led by Australian researcher Raina MacIntyre and conducted on Chinese hospital staffers in Beijing, China, from 2009-2010 suggested the exact opposite conclusion. Specifically, the results of the study argued that the staffers who wore N95 respirators "all the time" experienced much lower rates of respiratory illnesses than those who wore surgical masks, or who only wore N95 respirators in specific instances at work.
Of course, the efficacy of any mask will depend on whether or not you wear it correctly. "For [an N95 respirator] to be worn properly, it must fit over the nose and mouth, coming in contact with smooth skin," explains Dr. Mariea Snell, M.D., an assistant director of the Online Doctor of Nursing Practice program at Maryville University. "Facial hair would impact its ability to make the seal it needs to be effective." Like Kelly, she doesn't recommend wearing one as a preventative measure unless you know you'll be in contact with someone who's infected.
To remove the mask, The Washington Post recommends you treat it as if it is contaminated, and take it off by touching the straps, rather than the mask itself. In the video above, you can see a tutorial for how to properly put on and take off a mask, as done by infectious disease specialist Wing Hong Seto.
If you want to stay up to date on the latest news about coronavirus, Snell suggests taking advantage of your social media apps. "Social media is a great way to get up to date information," she says. "Following the CDC and World Health Organization (WHO) on Twitter and Instagram will provide you access to the latest information as things develop." In the meantime, you probably shouldn't worry about rushing to the store for a mask.
Radonovich, L. (2019), N95 Respirators vs Medical Masks for Preventing Influenza Among Health Care Personnel. The Journal of the American Medical Association, https://jamanetwork.com/journals/jama/fullarticle/2749214
MacIntyre, R. (2013), A Randomized Clinical Trial of Three Options for N95 Respirators and Medical Masks in Health Workers. American Journal of Respiratory and Critical Care Medicine, https://www.atsjournals.org/doi/full/10.1164/rccm.201207-1164OC