You’re Getting Used to Masks. Will You Wear a Face Shield?

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The debate over whether Americans should wear face masks to control coronavirus transmission has been settled. Governments and businesses now require or at least recommend them in many public settings. But as parts of the country reopen, some doctors want you to consider another layer of personal protective equipment in your daily life: clear plastic face shields.

“I wear a face shield every time I enter a store or other building,” said Dr. Eli Perencevich. “Sometimes I also wear a cloth mask if required by the store’s policy.”

Dr. Perencevich is an infectious disease physician at the University of Iowa and the Iowa City Veterans Affairs Health Care System. In an opinion article published last month in JAMA, he and two colleagues argued that simple, clear plastic face shields could help reduce the transmission of infections when added to public health measures like increased testing, contact tracing, social distancing and hand hygiene.

The idea is not just a thought experiment. In Singapore, preschool students and their teachers will receive face shields when they return to school next month. Local health experts recommended teachers in Philadelphia wear shields when schools reopen, and a teachers union in Palo Alto, Calif. requested them as well.

But it can be difficult to imagine Americans being willing to put on another form of protective equipment. President Trump and Vice President Mike Pence have shirked wearing masks in settings that would seem to call for them, and simple face covering requirements have provoked conflicts at grocery stores and restaurants.

Face shields have long been required equipment for many procedures in hospitals. Doctors and nurses wear them when intubating Covid-19 patients and during surgeries that may cause blood and bone fragments to fly out.

As debate arose over whether tiny coronavirus droplets could float on air currents, protecting the eyes and the entire face became a bigger issue in health care settings, said Dr. Sherry Yu, a dermatology resident affiliated with Brigham and Women’s Hospital in Boston. People needed them to do nasal swabs for the coronavirus test or for triage in the emergency room. As shortages loomed, Dr. Yu was among the many people and groups around the country who began fabricating face shields for front-line health care workers.

“The nice thing about face shields 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.

Surgical masks and N95s, on the other hand, are meant to be disposed after each use, although some studies have shown masks can be reused two or three times after being sterilized before they lose integrity.

Dr. Perencevich believes that face shields should be the preferred personal protective equipment of everyone for the same reason health care workers use them. They 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.

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. And while cloth masks can prevent people from spreading germs to others, they don’t usually protect the wearer from infection.

Face shields can also aid people who depend on lip-reading, Dr. Perencevich said. They may be slightly dorky-looking, but the shields allow facial expressions and lip movements to remain visible, while serving as an obvious reminder to maintain social distancing.

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Still, he and other experts acknowledge that face shields have their limits.

Just like masks, they must be removed when eating in cafeterias or restaurants. And studies on how effectively they can reduce a person’s viral exposure are scarce.

Video

Cinemagraph
In a video played at 1/8th speed, aerosols are expelled into a face shield at a distance of 18 inches. Video by Lindsley et al, 2014/NIOSH

One cough simulation study in 2014 suggested that a shield could reduce a user’s viral exposure by 96 percent when worn within 18 inches of someone who was coughing. But most people in the general public are much farther away from others they are interacting with, said William Lindsley, a bioengineer at the National Institute for Occupational Safety and Health who led the study. Large droplets that may contain virus will fall to the ground quickly, reducing the need for a face shield worn when standing farther away.

Even in close range, there can be scenarios where face shields are not as effective as masks like N95s that create a seal around one’s face. “If you’re facing sideways, or I’m behind you, maybe you’re sitting at a desk and I’m standing, there’s other scenarios you can imagine where droplets can come around a face shield,” Dr. Lindsley said.

  • Frequently Asked Questions and Advice

    Updated May 20, 2020

    • What are the symptoms of coronavirus?

      Common symptoms include fever, a dry cough, fatigue and difficulty breathing or shortness of breath. Some of these symptoms overlap with those of the flu, making detection difficult, but runny noses and stuffy sinuses are less common. The C.D.C. has also added chills, muscle pain, sore throat, headache and a new loss of the sense of taste or smell as symptoms to look out for. Most people fall ill five to seven days after exposure, but symptoms may appear in as few as two days or as many as 14 days.

    • How many people have lost their jobs due to coronavirus in the U.S.?

      Over 38 million people have filed for unemployment since March. One in five who were working in February reported losing a job or being furloughed in March or the beginning of April, data from a Federal Reserve survey released on May 14 showed, and that pain was highly concentrated among low earners. Fully 39 percent of former workers living in a household earning $40,000 or less lost work, compared with 13 percent in those making more than $100,000, a Fed official said.

    • How can I protect myself while flying?

      If air travel is unavoidable, there are some steps you can take to protect yourself. Most important: Wash your hands often, and stop touching your face. If possible, choose a window seat. A study from Emory University found that during flu season, the safest place to sit on a plane is by a window, as people sitting in window seats had less contact with potentially sick people. Disinfect hard surfaces. When you get to your seat and your hands are clean, use disinfecting wipes to clean the hard surfaces at your seat like the head and arm rest, the seatbelt buckle, the remote, screen, seat back pocket and the tray table. If the seat is hard and nonporous or leather or pleather, you can wipe that down, too. (Using wipes on upholstered seats could lead to a wet seat and spreading of germs rather than killing them.)

    • Is ‘Covid toe’ a symptom of the disease?

      There is an uptick in people reporting symptoms of chilblains, which are painful red or purple lesions that typically appear in the winter on fingers or toes. The lesions are emerging as yet another symptom of infection with the new coronavirus. Chilblains are caused by inflammation in small blood vessels in reaction to cold or damp conditions, but they are usually common in the coldest winter months. Federal health officials do not include toe lesions in the list of coronavirus symptoms, but some dermatologists are pushing for a change, saying so-called Covid toe should be sufficient grounds for testing.

    • Should I wear a mask?

      The C.D.C. has recommended that all Americans wear cloth masks if they go out in public. This is a shift in federal guidance reflecting new concerns that the coronavirus is being spread by infected people who have no symptoms. Until now, the C.D.C., like the W.H.O., has advised that ordinary people don’t need to wear masks unless they are sick and coughing. Part of the reason was to preserve medical-grade masks for health care workers who desperately need them at a time when they are in continuously short supply. Masks don’t replace hand washing and social distancing.

    • What should I do if I feel sick?

      If you’ve been exposed to the coronavirus or think you have, and have a fever or symptoms like a cough or difficulty breathing, call a doctor. They should give you advice on whether you should be tested, how to get tested, and how to seek medical treatment without potentially infecting or exposing others.

    • How can I help?

      Charity Navigator, which evaluates charities using a numbers-based system, has a running list of nonprofits working in communities affected by the outbreak. You can give blood through the American Red Cross, and World Central Kitchen has stepped in to distribute meals in major cities.


There is also no research on how well one person’s face shield protects other people from viral transmission, the concept called source control that is a primary benefit of surgical and cloth masks.

One of the main reasons the Centers for Disease Control and Prevention changed their recommendations to suggest everyone wear a face covering in public was to protect others in case they were among the asymptomatic or pre-symptomatic group of people infected with the virus.

“I’m a huge fan of face shields,” said Saskia Popescu, a senior infection-prevention specialist at George Mason University in Fairfax, Va. “But I don’t think we can swap them out for face masks just yet.”

Dr. Perencevich and his colleagues expect that more research will show shields to be superior to cloth masks, not only because shields provide full face protection but as they are nearly impossible to wear incorrectly.

“Remember, effectiveness depends not only on the inherent properties of the facial covering but also how well the facial covering is worn,” he said.

And he and his co-authors like to imagine that people who are reluctant to wear masks will find face shields more comfortable: Once a person tries one on, they say, the wearer realizes its many benefits.