Hong Kong has so far reported a grand total of four coronavirus-related deaths, while New York City has reported over 20,000.

Heres another striking comparison: Close to 99 percent of Hong Kong residents have been wearing masks, to prevent the wearer from spreading the virus, since early February. According to a mid-April Gallup poll, only a third of Americans say they always wear a mask or cloth face covering outside the home. Another third of us sometimes wear a mask in public, and a third never do.

Universal face mask adoption isnt the only difference between Hong Kong and the United States, and its not a substitute for physical-distancing, hand-washing and other preventive practices. But masks even just a scarf, bandanna or an old T-shirt and two rubber bands are widely viewed as critical to stopping the transmission of the novel coronavirus.

Nevertheless, face-mask compliance on this side of the Pacific has been uneven. This is especially worrisome in closed, crowded spaces like subways and buses, grocery stores and offices where its not easy to maintain a distance of six feet from other people and avoid spontaneous coughs and sneezes.

The most obvious path to universal masking is to pass laws and punish infractions. But enforcing legal edicts to wear masks in public can be difficult and costly, and amid widespread ambivalence can lead to backlash and even violence. So edicts are not a complete solution.

As experts in public health and human behavior, we propose a complementary approach: Make wearing a mask easy, understood and expected.

From effortful to easy: Where can you get face masks? You can search for them online, you can now buy them in drugstores and yes, you can make them yourself. But none of these options are effortless.

Imagine if every city and town in this country had an Adrian Cheng, the real estate developer in Hong Kong who had a manufacturing line set up in one of his empty properties and made the masks available free to the needy in vending machines devised specifically for the purpose. Not long after, the Hong Kong government set up a website where any household can register to have reusable masks delivered free. Or consider Utah, where residents can likewise register online and receive a free fabric face mask by mail. The cheaper and more ubiquitous face masks are, the easier it will be for Americans to get our hands on them, and the more likely well do so and wear them.

From unclear to understood: Not long ago, the Centers for Disease Control and Prevention and the surgeon general were lecturing the American public on why they shouldnt wear face masks. That recommendation flipped once it became clear that people infected with the coronavirus can spread it before they know they have it and, therefore, everyone should wear a mask to reduce the chances of infecting others. Since its hard for people to update their beliefs once a message has been received, its no surprise that misinformation and outdated news continue to ricochet in the echo chambers of social media.

Unfortunately, it is often easier to dig our heels in than to change our minds, defending our original position and discounting new information to justify our behavior. Therefore, it can be helpful to supply people with a rationale to change their behavior without looking like a hypocrite. For example, officials can emphasize that at the start of this crisis, nobody could have known how important it is to wear a mask when you have no symptoms, and that day by day, new scientific evidence is demonstrating the efficacy of masks in the fight against the coronavirus.

From unconventional to expected: It is human nature to adhere to social norms. When uncertain about what to do, people tend to look around and copy what other people are doing. For instance, if you were in Hong Kong right now, even if you werent up to date on the public health imperative, youd very likely follow the lead of everyone around you and put one on.

How do we create a social norm of mask-wearing when, in fact, so many Americans are doing exactly the opposite? One common mistake is drawing attention to the lack of compliance. For instance, highlighting littering as a commonplace problem can inadvertently lead to more littering because it strengthens the perception that littering is the norm. Instead, in press releases and public service announcements, officials should emphasize that the clear trend in this country is toward universal mask-wearing.

According to a recent Qualtrics study, a majority of surveyed Americans now say they wont return to the office unless their company makes wearing face masks mandatory. And in just one week in April, the percentage of Americans who said they wore a mask outside the home increased by more than half.

The story of face masks in this country is still being written. We may lack the wisdom Hong Kong earned weathering prior epidemics, but its not too late to apply three basic principles from behavioral science: make it easy, understood and expected, and well soon see face masks everywhere, saving lives.

Angela Duckworth, founder and chief executive of Character Lab, is a professor at the University of Pennsylvania, where Lyle Ungar is a professor of computer and information science, and Ezekiel J. Emanuel, author of the forthcoming Which Country Has the Worlds Best Health Care?, is a professor of health care management, medical ethics and health policy.

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There Are 3 Things We Have to Do to Get People Wearing Masks - The New York Times