Wait—Now I Should Wear a Mask?

Yale Medicine experts explain the reasoning behind the CDC’s new guidelines.

people wearing face masks to protect against COVID-19, the novel coronavirus

The Centers for Disease Control and Prevention (CDC) now recommends that people voluntarily wear cloth face coverings in public settings to help prevent community-based transmission of COVID-19. Yale Medicine experts tell you what you need to know.

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Just few months ago, wearing a mask to avoid exposure to germs at the bank, the supermarket, or during a walk in the park would have seemed a little excessive here in the United States. But as the threat of COVID-19 intensified, more people started to wear them.

Then, in early April, the Centers for Disease Control and Prevention (CDC) recommended that people voluntarily begin wearing cloth face coverings in public settings such as grocery stores and pharmacies, where other social distancing measures are difficult to maintain—especially in cities, towns and other places where there have been significant community-based transmission of COVID-19.

But, why wear a mask now?

“We should do everything we can to slow the spread of the virus,” says Joseph Vinetz, MD, a Yale Medicine infectious disease specialist. But, he added that people should understand that a mask is just one small tool in the toolbox. “A mask should not give anyone a false sense of security. It doesn’t give you a license to have social gatherings. It’s just a way to help reduce whatever small amount of transmission could be going on in public.”

There are four key things you should know about the CDC’s face mask recommendations:

  • A mask can be made from simple materials . It can be a basic covering that you make yourself using materials you find around the house—even a T-shirt. The CDC does not recommend using surgical masks or N95 respirators (devices worn to block airborne particles). These are critical supplies needed by health care workers who may be at high risk for exposure to COVID-19 infection.
  • A mask is meant to protect others, not yourself. Whether or not you are feeling sick or have COVID-19 symptoms, there is evidence that if you have the virus, you may be able to transmit it to others when you speak, cough, or sneeze.
  • The mask recommendation is not for everyone. The advice doesn’t apply to children younger than 2, people who have trouble breathing, or anyone who is unconscious, incapacitated, or otherwise unable to remove the mask without assistance.
  • Don’t abandon other preventive measures. The president’s Coronavirus Guidelines for America, 30 Days to Slow the Spread remains the cornerstone of the national effort to slow the spread of the novel coronavirus. These guidelines also urge Americans to work or study from home if they can, avoid gatherings of more than 10 people, and practice good hygiene that includes hand washing and not touching your face.

The CDC’s advice was a turnaround from previous recommendations which said that the only people who needed masks (other than health care workers) were those who were sick or caring for someone who was ill and unable to wear one. It says its new recommendation is based on recent studies that show that a significant number of people with the novel coronavirus who don’t have symptoms can still transmit the virus to others.

“The science is evolving, and the CDC is reflecting that,” Dr. Vinetz says. “We should be doing what the CDC recommends. It won’t eliminate the virus, but it will perhaps reduce the rate of transmission.” It also helps that a person who is wearing a mask is less likely to touch their face, he says. People are thought to put themselves at greater risk for infection when they transmit pathogens from their hands to their eyes, nose, and mouth when they touch their face.

Naftali Kaminski, MD, is chief of Yale Medicine Pulmonary, Critical Care, and Sleep Medicine, which serves a patient population that is especially vulnerable to serious complications if they get COVID-19. He believes that wearing masks can complement other efforts to slow the overall spread of COVID-19. “Prevention of infection is, in some ways, a numbers game,” he says. “You are taking multiple measures and all of them are supposed to contribute to preventing the spread of the disease.” Wearing a mask is one of those measures, he says. “While a cloth mask is not perfect, it does reduce air exchange between people. You mostly protect others and you do protect yourself a little bit.”

Both doctors agree that wearing a mask is a shift for Americans, while people in Asia have used masks to prevent spreading germs during flu season long before COVID-19 was identified. “Making an effort to prevent ourselves from infecting other people—that’s a cultural shift,” Dr. Vinetz says. “Even if a mask doesn’t protect my health, this is a way to show I care about others.”

How to make and use your own COVID-19 face mask

The CDC provides both “sew” and “no-sew” instructions for making and using a cloth face mask. It says these cloth face coverings should do the following:

  • Fit snugly but comfortably against the side of the face
  • Be secured with ties or ear loops
  • Include multiple layers of fabric
  • Allow for breathing without restriction
  • Be able to be laundered and machine dried without damage or change to shape (you can use a washing machine to properly wash a face covering)

The World Health Organization (WHO), which still maintains that healthy people only need face masks if they are caring for someone who is suspected of having COVID-19, provides these guidelines for using a mask:

  • Before putting on a mask, clean hands with soap and water or an alcohol-based hand rub.
  • Cover your mouth and nose with the mask and make sure there are no gaps between your face and the mask.
  • Avoid touching the mask while using it; if you do, clean your hands with an alcohol-based hand rub or soap and water.
  • Replace the mask with a new one as soon as it is damp, and do not re-use single-use masks.
  • To remove the mask: remove it from behind (do not touch the front of mask); discard immediately in a closed bin; clean hands with an alcohol-based hand rub or soap and water.

For anyone who is still wondering whether to wear a mask, Dr. Kaminski says a smart strategy is to follow all the official recommendations for preventing the virus, including the wearing of masks. “Follow the advice and err on the safety side,” he says. “One thing we’ve seen in this crisis is that those who err on the side of safety often do better.” 

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