Mike Segar / Reuters

Two days ago—an eon in coronavirus time—the Broadway producer Scott Rudin announced that tickets to some hit shows, including The Book of Mormon and West Side Story, would be available for just $50. “This is an unprecedented opportunity,” he said, “for everyone to see a show that they otherwise might not have had easy and affordable access to.”

In the midst of the great flu pandemic of 1918, a young manager named Harold Edel decided to encourage attendance at his movie theater in the city. It was featuring the new Charlie Chaplin film, Shoulder Arms, and the crowds were so large that Edel extended its run. The manager was so enthusiastic that he took out a full-page ad in the weekly Moving Picture World. While other theaters had been shunned, he wanted to congratulate patrons who “take their lives in their hands to see it.”

At the bottom of the ad, double-underlined and in a huge font, was the recommendation of the board of health to “AVOID CROWDS.” Edel’s ad continued: “New Yorkers took their life in their hands and Packed the Strand Theatre all week.” Edel, alas, never got to see his ad in print. He died of influenza before it went to press. And on Thursday this week, New York announced that it will be shuttering Broadway.

As I’ve written before, this is no 1918, but the pandemic a century ago left us with several lessons in public-health management and mismanagement, and it provides important information about whether or not banning public gatherings is an effective intervention.

During the terrible pandemic of 1918, all public-health responses were hobbled by the fact that the cause of the outbreak was unclear. Although it would take another 15 years to identify a virus as the culprit, influenza was generally understood to be spread through close contact. Despite this, there was, at least for a while, no ban on large public gatherings. In September, in the midst of both the war effort and the pandemic, the city of Philadelphia held the Liberty Loan Parade. Local newspapers reported that more than 100,000 people thronged the streets. Deaths from the flu quickly spiked. Soon 100 people a day were dying. The Liberty-bonds march had actually liberated the virus.

In contrast, St. Louis canceled its parade and very quickly introduced a number of efforts to promote social distancing. As a result, the excess mortality rate in the city was less than a third the rate in Philadelphia.

Keeping a safe distance from one another takes a lot more work than simply skipping a Broadway show. In 1918, measures included closing schools and churches, staggering business hours to reduce congestion on the transit system, and quarantining households where a member had been diagnosed with influenza. Other restrictions were appropriate for the time that today seem rather quaint. Dance halls were closed, door-to-door sales were banned, and you could be arrested for spitting in public. Researchers looking at how these measures affected mortality in 17 cities across the U.S. discovered that cities that aggressively implemented multiple interventions early on had peak death rates that were half those of cities that failed to do so. That’s a remarkable decrease, and surely supports the cancellation of many public gatherings today, from political rallies to basketball games.

The lessons from school closings are more mixed. Across New York State, decisions varied; the city kept its school system open, though Albany and Rochester closed for weeks. Elsewhere, Chicago kept its school system open, but Pittsburgh, Baltimore, and Portland closed theirs. Cleveland adopted a smart approach of ongoing reassessment. If more than 20 percent of the children were absent at a local school, it would be closed. If more than 10 percent were absent from a school district as a whole, it, too, closed. This rapid-feedback system gave teachers more autonomy, and increased cooperation between health departments and school districts.

Do school closings help limit the spread of influenza? It’s a tough question to answer definitively, but at best they appear to have a moderate effect in reducing transmission, if—and this is important—the rate of illness from influenza in children is high compared with adults. One unusual feature of COVID-19 is that children seem to be largely spared from illness. This means that school closings would do less to reduce its spread than the precedents of 1918 might suggest.

Another feature of school closings must be taken into account, and it goes beyond the fact that many parents would need to stay at home to take care of their children. As the weather warms up, children will do what they always do. They will climb trees or chase basketballs into busy streets, and a few unlucky ones will end up in emergency rooms with serious injuries—or worse. Like medications, public-health interventions have unwanted side effects. While it is relatively easy to decide to close down a school system, it takes wisdom to understand the ramifications of a choice that will take millions of children out of relatively safe environments and put them into others, where the risks are unknown. Pity the public servant who has to make that call.

Once states close their schools, or theaters, or public gatherings, they will be forced to grapple with another problem. Public closings cannot last forever. They must, sooner or later, be lifted. And that’s when the story gets more complicated. “Interventions may be capable of significantly reducing the rate of disease transmission so long as they remain in effect,” a team of researchers wrote in 2007. But while the mortality rates declined during closures, once they were relaxed, the influenza virus found fertile new territory.

In fact, cities that reduced their rates of transmission with aggressive public-health measures experienced a large bounce and a second wave of infection. Public closings do not necessarily keep infections out of our communities. They may only delay their arrival. But that delay may itself be crucial. When people who are sick arrive within a short period, they can overwhelm hospitals and clinics—and quickly use up essential supplies. When that same number of sick people is spread out over a longer period of time, health-care providers are more likely to be able to cope with the demand.

For the next few weeks, closings will become a part of our way of life. Then we really will have something in common with those who lived through the great influenza pandemic of 1918.

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