If history is an indicator, we are in this for the long haul. In spite of our most fervent wishes to get outside and enjoy the rites of spring—college graduations, Mother’s Day, youth sports—life is unlikely to return to normal anytime soon. The great influenza of 1918, considered the deadliest pandemic in modern history, offers a social distancing roadmap for tackling today’s COVID-19.

After Philadelphia detected its first case of flu in September 1918, leaders warned people about openly coughing and sneezing, but ten days later the city hosted a parade attended by 200,000 people. The number of influenza cases continued to mount, and two weeks after the first case there were 20,000 more. Several cities (St. Louis's Red Cross