Why masks work, but warrants don’t

Covid cases and hospitalizations are rising again in the United States, and deaths are starting to rise as well. In response, many people are rightly asking what the country can do to minimize the toll of the virus in the coming weeks.

Much of the discussion so far has focused on mask mandates. Schools in Philadelphia; Providence, RI; Berkeley, California.; and Brookline, Massachusetts, have reimposed theirs, as have several colleges. Elsewhere, some people are frustrated that officials like New York Mayor Eric Adams have not done so.

Critics have accused these leaders of lacking political courage, saying they are giving in to Covid fatigue rather than imposing necessary public health measures. But I think the critic is misinterpreting both public health history and recent scientific evidence on mask mandates.

Evidence suggests broad mask mandates have done little to reduce the number of Covid cases over the past two years. Today, mask rules can do even less than in the past, given the contagiousness of current versions of the virus. And successful public health campaigns rarely involve a divisive struggle over a measure unlikely to make a big difference.

Since the start of the pandemic, there has been a paradox around masks. As Dr. Shira Doron, an epidemiologist at Tufts Medical Center, the dish“It’s true both that masks work and mask mandates don’t work.”

To start with the first half of the paradox: masks reduce the spread of the Covid virus by preventing virus particles from traveling from a person’s nose or mouth through the air and infecting another person. Laboratory studies have repeatedly demonstrated the effect.

Given this, one would think that communities where mask-wearing has been more common would have had far fewer Covid infections. But that was not the case.

In US cities where mask use has been more common, Covid has spread at a similar rate to mask-resistant cities. Mask mandates in schools also seem to have done little to reduce the spread. Hongkong, despite wearing the almost universal maskrecently suffered one of the world’s worst Covid outbreaks.

Proponents of mandates sometimes argue that they have a large effect even if it is not evident in population-wide data, due to the number of other factors at play. But this argument seems unconvincing. .

After all, the effect of vaccines on serious diseases is extremely evident in geographical data: places with higher vaccination rates have suffered far fewer deaths from Covid. The patterns are clear even though the world is a messy place, with many factors other than vaccines influencing Covid death rates.

Yet when you look at the data on mask wearing — both before vaccines became available and after, as well as in the United States and abroad — you struggle to see any trends.

The idea that masks work better than mask mandates seems to defy logic. It reverses a notion linked to the writings of Aristotle: that the whole must be greater than the sum of the parts, not less.

The main explanation seems to be that the exceptions often end up being more important than the rule. The Covid virus is so contagious that it can spread during brief periods when people remove their masks, even when a mandate is in place.

Airplane passengers take off their masks for a drink. Restaurant customers pass without a mask as soon as they walk through the door. The schoolchildren let their masks slide over their faces. Adults too: Research from the University of Minnesota suggests that between 25 and 30 percent of Americans consistently wear their masks under their noses.

“Even if masks work, getting millions of people to wear them, and to wear them consistently and correctly, is a much bigger challenge,” wrote Steven Salzberg, a biostatistician at Johns Hopkins University. Part of the problem, Salzberg explains, is that the most effective masks also tend to be less comfortable. They cover more of a person’s face, fit better, and restrict the flow of more air particles.

In an acute crisis – like the early months of Covid, when masks were one of the few forms of protection available – strict guidelines may nevertheless make sense. Public health officials can urge people to wear well-fitting, high-quality masks and never take them off in public. If the mandate has even a modest benefit, it may be worth it.

But this approach is not sustainable for years. Masks hinder communication, glasses fog up and can be uncomfortable. There’s a reason children and airline passengers erupted in applause when told they could take their masks off.

At the current stage of the pandemic, there are less confrontational measures that are more effective than mask mandates. Booster shots are widely available. A drug that can further protect immunocompromised people, known as Evusheld, is becoming increasingly available. The same goes for post-infection treatments, like Paxlovid, which make Covid less severe.

(For young children, who are not yet eligible for the vaccine, Covid is extremely mild, similar in severity to the flu.)

Continuing to expand access to these treatments can do more to reduce Covid hospitalizations and deaths than any mask rule likely would. “People have the means to protect themselves,” Dr. Robert Wachter, chair of the department of medicine at the University of California, San Francisco, told me. Absent a much larger rise in Covid hospitalizations, he added, the case for mandates is weaker than before.

Dr. Aaron Carroll, director of health at Indiana University, recently wrote for the Opinion section of The Times: “Instead of continuing to bicker over things that have become hopelessly politicized like mask mandates, public health officials could focus on efforts that could make much more of a difference.

Available data also suggests that more than half of Americans have had Covid in the past six months, making many of them unlikely to contract it again now. As Jennifer Nuzzo, an epidemiologist at Brown University, said to Vox“A lot of people who don’t wear masks have already had Covid, so they’re like, ‘I’ve been vaccinated, I’ve already had it — how long do you want me to do this?’ And it’s kind of hard to say, ‘No, you absolutely have to wear it.’ »

The country will likely never come to a consensus on masks. They have become another source of political polarization. Democrats are more likely to wear masks than Republicans, and Democrats who identify as “very liberal” are more likely to support mandates.

Fortunately, the scientific evidence points to a reasonable compromise. Because masks work and warrants often don’t, people can make their own decisions. Anyone who wants to wear a comfortable, high-quality mask can do so and will be less likely to contract Covid.

Rather, this approach — one-way masking — is consistent with what hospitals have been doing for a long time, as Tufts epidemiologist Doron points out. Patients, including those with infectious diseases, generally did not wear masks, unlike doctors and nurses. “One way masking is the way we’ve always used them,” she wrote.

The same system can work for Covid outside of hospitals. Wachter, for example, believes the days of warrants are over but still wears one in the supermarket, in classrooms, on airplanes and elsewhere. Different people can reasonably make different choices.

A weekly show where immigrants cook takeout, called United We Eat @Home, turned Ghalia Ahmad Fayez AlMasri into a local celebrity in Missoula, Mont. “When I cook, my meal goes very, very fast – 15 minutes this time,” AlMasri, who fled Syria in 2017, told The Times.

The program has helped refugees apply for permits for farmers’ markets and find jobs in catering. And he’s diversified the city’s food scene: Without him, Missoulians wouldn’t have a place to order Congolese, Pakistani or Guinean food. Here is more information about the program, as well as appetizing photos.

Maria D. Ervin