In the fall of 1918, as the deadly second wave of the influenza pandemic known as the “Spanish flu” swept across the nation, schools in cities around the United States closed in order to limit contagion.

But in the nation’s two largest urban centers, New York and Chicago, public schools remained open—even during October 1918, the flu’s deadliest month, when some 195,000 Americans died. Health officials in both cities placed their bets on newly robust school hygiene and medical inspection programs, which reformers of the Progressive Era had put in place over the decades before the flu hit.

In the late 19th century, public school enrollment in the United States exploded, with total enrollment increasing by 44 percent in the 1870s alone. Enrollment continued to grow over the next few decades, largely driven by the increase in the nation’s total population. By 1918, more American children were attending public schools than ever before.

Attendance rates also saw steady improvement after the 1850s, as one state after another passed compulsory attendance laws. When Mississippi enacted mandatory attendance legislation in 1918, all U.S. states had such laws in place for the first time.

But for social and educational reformers, it wasn’t enough that children attend school—they also needed to stay safe and healthy when they got there. Schools were renovated and reorganized to allow better ventilation in classrooms and ensure access to fresh drinking water. Beginning in the 1890s, many cities launched medical inspection programs, with doctors visiting schools to check on students’ health and identify any ailments, from head lice to tuberculosis.

In 1902, Lina Rogers became the nation’s first school nurse, when she was hired to improve student health and attendance at four New York City schools. Absenteeism fell by 90 percent within six months of her coming on the job, and by 1914 the city’s schools employed nearly 400 nurses.

READ MORE: When American Students Attended School Outside

As the second wave of the Spanish flu hit in September 1918, Dr. Royal S. Copeland, a homeopathic physician and the city’s health commissioner, initially considered school closures as a way of limiting the pandemic’s spread. But Dr. S. Josephine Baker, director of the Department of Health Bureau of Child Hygiene and a leading Progressive reformer, persuaded Copeland to keep the city’s schools open, according to a 2010 article co-authored by Dr. Alexandra Stern. Baker argued that kids were better off contained in schools, and that regular medical inspections could identify sick students and keep healthy ones safe.

At the time, New York City’s public school system contained close to 1 million children, and 750,000 of those lived in crowded and often unsanitary tenement homes. In an article headlined “Epidemic Lessons Against Next Time,” published in the New York Times in November 1918, after the worst of the pandemic had passed, Copeland described the advantages in keeping the schools open: “[Children] leave their often unsanitary homes for large, clean, airy school buildings, where there is always a system of inspection and examination enforced,” he said.

Students with any symptoms were immediately isolated, Copeland explained. If they were feverish, they were sent home, after which a health official would be sent to their homes to determine if they could recover there or needed to be sent to a hospital.

Copeland himself was annoyed when his son’s private school, the Ethical Culture School, closed its doors in mid-October. According to another report in the Times, the commissioner blamed his son’s case of influenza on his not being in school, arguing that “children are better off in school, under supervision, than playing about in the streets.”

READ MORE: Why the Second Wave of the Spanish Flu Was So Deadly

Like Copeland, Chicago’s health commissioner, John Dill Robertson, made the controversial decision to keep schools open during the worst of the 1918-19 flu pandemic. The city already had a strong medical inspection program in schools by that time, and Robertson and other health officials believed that children would be better off in school than at home, or on the streets, with relatively limited supervision

Despite this belief, many parents in Chicago opted to keep their children home anyway: Stern and her co-authors reported that absentee rates went from 30 percent in early to mid-October 1918 to nearly 50 percent late that month. Robertson later suggested parents were keeping children home because of what he called “fluphobia.”

In addition to New York and Chicago, officials in New Haven, Connecticut also kept schools open during the pandemic, and saw similarly high rates of absenteeism—among teachers as well as students. In all three cities, the role of medical inspections and school nurses proved crucial in enabling schools to stay open, and proved to many the value of the reforms instituted in previous decades.

Compared to other major cities in the Northeast, like Boston and Philadelphia, New York weathered the influenza pandemic reasonably well, and many credited Copeland with limiting the damage and keeping people (relatively) calm.

In 1922, Copeland ran successfully for the U.S. Senate; a young Franklin D. Roosevelt served as the honorary chairman of his campaign. Copeland would serve three terms as a senator until his death in 1938, and gained enduring fame for his successful efforts to install air conditioning in the Senate Chamber.

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