1918 flu historian: Rushing to return to normal can kill

I am a historian of pandemics. Like an accountant preparing his clientele’s income taxes, you might say, “This is my busy season!”

From 2005 to 2007, I led a group of historians at the University of Michigan, who worked with epidemiologists at the U.S. Centers for Disease Control and Prevention, to study the use of social distancing measures during the 1918-19 influenza pandemic. That pandemic still holds the record as the worst contagious crisis in human history. It ended about 40 million lives worldwide, including up to 550,000 Americans.

We looked at how 43 large American cities responded to that contagious crisis with some combination of isolating the ill and quarantining suspected cases; banning public gatherings; and closing down schools.

In the cities that acted early, for sustained periods, and used more than one social distancing measure at a time, we found the case and death rates to be significantly lower compared to the cities that did not take such measures.

Indeed, this is where the concept of “flattening the curve” originated, soon to be buried in a 2007 CDC report on pandemics only to be given new life, force and power in the COVID-19 era.

Social distancing works

By now, many have pointed out the comparisons between St. Louis and Philadelphia during the fall of 1918. St. Louis acted early, with layered and sustained measures, and enjoyed one of the lowest mortality rates in America. In Philadelphia, battles between politicians, slow responses, and huge crowds at Liberty Loan parades led to a massive increase in influenza cases after such gatherings. In fact, Philadelphia suffered the second worst death rates in the U.S., after Pittsburgh.

A key finding of our work was that social distancing measures must be enforced for long periods of time until the virus becomes quiescent. That’s because in 1918 as with today, these measures do not cure or prevent viral infections. They only allow us to hide from infection, reduce the number of people flooding hospitals at any given moment, and buy time to develop new therapies and vaccines.

Back in 1918, the people of Atlanta soon grew weary of their city’s version of a lockdown against influenza. As a result, the mayor re-opened the city after only about two weeks of closures. His Board of Health objected because they predicted that Atlanta’s peak number of cases was not due for another nine days. The mayor dismissed their scientifically informed advice and countered that there was no way to predict the future.

Atlanta’s Public Safety Committee agreed and pronounced, “The influenza situation in Atlanta is up to the people themselves.” Guess what happened? Atlanta’s fall wave of the epidemic raged on, unchecked, through the end of 1918, and well into the winter of 1919.

Returning to ‘normal’ can be deadly

In every city we studied, there was public pressure to quit the social distancing measures as soon as the influenza epidemic seemed to peak and then ebb.

Thinking that all was well, many cities lifted these measures before the viral battle had actually ended. Inevitably, the case and death rates ballooned because the virus was still circulating.

In other words, once people stopped hiding from it, many became ill and died. In some cities, such as Kansas City, Milwaukee, Denver, and even St. Louis, this second peak was deadlier than the first.

As we ponder how to best return to normal life today, we must work from the premise that as long as this deadly virus stalks the planet, longer is better than shorter.

These measures are imperfect and slow to work. They are disruptive and painful to our daily lives and economy. They do not magically end pandemics. But they can save lives.

And that may well be the most important lesson of the 1918 influenza pandemic.