CHICAGO (WLS) -- The push to reopen the economy while protecting public health is not new to the U.S. or Chicago; it happened just over 100 years ago, during the Spanish flu.
The Spanish influenza pandemic of 1918 was the deadliest in history. It infected about one third of the world's population and claimed somewhere between 20 and 50 million lives.
Closed businesses, masks, and stay-at-home orders were all part of the safety measures taken during that pandemic, and there was also a similar push to reopen economies.
"For cities and states that opened too early, there was a direct correlation between an increase in mortality rates and a decrease in the speed at which the economis reopened," said Brittany Hutchinson of the Chicago History Museum.
Hutchinson said during the Spanish flu Philadelphia tried to return to normal by holding a parade. That parade increased the number of people who were infected and ultimately died from influenza.
Philadelphia was one of the country's hardest hit cities, in terms of infections and deaths. It was also one of the last to rebound economically.
Historians say the influenza pandemic offers lessons for municipalities outside Cook County who are urging Governor JB Pritzker to open sooner; in 1918, cities who chose to keep their labor forces healthy recovered more quickly.
"To ensure they are healthy guarantees in some way you have an economy to rely on," Hutchinson said.
Historians say Chicago was similar to many other cities in 1918, taking a moderate to aggressive approach to the pandemic.
"What I can say about Chicago, there were orders to arrest people who were sneezing without covering their sneeze or $10 fines if you went out in public," said Hutchinson.
Historians urge lawmakers who are anxious to reopen to follow the model of 1918. Continuing aggressive safety measures will pay off in the long run.