Lessons learned — and forgotten — from the horrific epidemics of the U.S. Civil War

As the U.S. approaches 600,000 deaths from Covid-19, it is hard to fathom that this calamity pales in comparison to America’s worst outbreak of epidemic diseases during and just after the Civil War.

From smallpox and measles to dysentery and typhoid, the Civil War, which lasted from 1861 to 1865, triggered an explosion of deadly epidemics on a scale never seen in the U.S., before or since. A million sick soldiers, newly emancipated ex-slaves, families caught in the crossfire, and hungry refugees died during the war, about 3% of the U.S. population. Two-thirds of these deaths were from disease. For comparison, it would take nearly 10 million Americans deaths from Covid-19 to reach the Civil War’s death toll.

As a medical historian, I’ve spent countless hours poring through vintage medical journals, public health reports, and eyewitness accounts of the health nightmare that was the Civil War. These sources are full of sobering parallels between that war and Covid-19, as well as the valuable but essentially forgotten lessons it taught the country about public health.

The mass movement of millions of people taught the Civil War generation that epidemic diseases flourish when people travel and gather. At the time the war broke out, four-fifths of Americans lived in rural settings and rarely strayed far from home, so they had limited exposure to the era’s childhood diseases, sicknesses like measles and smallpox that were typically contracted in urban populations during childhood and adolescence. When the rural young men who comprised the Civil War’s gargantuan armies began mobilizing in 1861, millions of recruits without immunity to smallpox and measles packed into crowded training camps, which rivaled the population density of the biggest cities in America and Europe. With unprotected populations exposed to unfamiliar pathogens, huge disease outbreaks followed, killing hundreds of thousands and putting entire units out of commission.

Civil War commanders learned their lessons. As the war dragged on, new recruits were “seasoned” in special camps, where they contracted and (hopefully) recovered from measles before shipping out. Those with smallpox were isolated in special hospital wards, and surgeons embarked on vaccination drives to eradicate this disease in the army. The efforts helped bring the measles and smallpox epidemics among soldiers under control.

A similar scenario transpired in early 2020 and 2021 when college students without immunity to Covid-19 flocked to America’s beaches for spring break. They then scattered, taking the virus back home with them and spreading it there. In the fall of 2020, when universities brought unprotected students back to campus, coronavirus cases surged in college towns across America. Stricter adherence to Civil War-era seasoning and isolation practices could have avoided repeating history 150 years later.

The Civil War’s health crisis also taught Americans in the 1860s and 1870s that the rigid enforcement of public health measures saves lives.

This was especially true of dysentery and typhoid fever, both spread by feces-contaminated water. The gigantic, mobile cities that were Civil War armies lacked even the basic standards of 19th-century sanitation, like groundwater drainage, trash removal, and air ventilation. Tents were too close together, overcrowded, and lacked clean water or good airflow.

Latrines were an even bigger problem for armies. Army guidelines dictated that privies be located outside of camps, but this was often sacrificed to the exigencies of war. Armies moved frequently, and soldiers didn’t relish the tiresome work of digging proper latrines. Most camps had informal, open-air latrines just a few feet — and sometimes less — from sleeping, cooking, and eating areas. The nauseating, overpowering stink, or miasma, worried army surgeons and sanitary inspectors. But even when they managed to get festering latrines moved away from camps, it didn’t stop exhausted soldiers from defecating just outside their tents, with human waste seeping into nearby water sources.

At Andersonville, a notoriously deadly Confederate prisoner-of-war camp located in a Georgia swamp, latrines were set up just a few yards from the ramshackle lean-tos in which Union prisoners ate and slept. The prison’s grassless, muddy ground was invariably splattered with puddles of fecal matter teeming with pathogens. The only source of drinking water, a stream that flowed through the prison grounds, was contaminated with human waste from a nearby Confederate camp. Exposure and starvation left the prisoners especially vulnerable to sickness. It’s not surprising that 13,000 of those at Andersonville — about a quarter of the prison population — died of diseases like dysentery, “chronic diarrhea,” and typhoid.

The place was so unhealthy that its Confederate commander was later convicted of war crimes and hung for neglecting to address public health issues there.

Horrified Civil War observers realized the obvious: that poor sanitation was causing far too many soldiers to die. So wartime relief organizations, like the United States Sanitary Commission, set about trying to convince army leaders and rank-and-file soldiers to clean up their acts. They taught soldiers to dig latrines farther away from camps and how to properly ventilate living spaces and hospitals. This full-court press eventually paid off. In camps and hospitals where army officers rigidly enforced sanitation rules, disease deaths plummeted.

After the war, army surgeons and medical volunteers returned home, spreading the news that strong, consistent enforcement of public health standards could save lives. They set to work creating the nation’s first modern boards of health to combat diseases like cholera and yellow fever. Cities like Chicago and New York began cleaning up filthy rivers, draining standing water, and enforcing quarantines.

This work paid off. Deaths from cholera and yellow fever, which had been major killers before the war, plummeted in the decades afterward. The war’s public health lessons saved countless lives, long before modern medical revolutions like the discovery of germs.

Had that faith in — and support of — public health been maintained, hundreds of thousands of deaths could have been avoided when Covid-19 emerged.

The Civil War also teaches the lesson that epidemics compound preexisting structural racism, hitting people of color the hardest. When the Union army and navy advanced into the South, enslaved people seized the initiative and took freedom into their own hands, fleeing plantations by the thousands to refugee camps behind Union lines. But in this chaotic mass migration, the U.S. government failed to offer medical assistance to these freed people. Like rural white soldiers, most former slaves lacked acquired immunity to measles and smallpox. Predictable outbreaks ravaged the refugee camps, killing thousands of people who had nothing but the clothes on their backs and no means to obtain medical care. Army officers and government officials willingly turned a blind eye, not bothering to isolate or vaccinate Black refugees, who died in droves.

One-hundred and fifty years later, in the early days of Covid-19, American leaders also overlooked Black and brown Americans, failing to provide equitable testing and high-quality care. This neglect led to higher Covid-19 death rates among communities of color, just as happened with smallpox during the Civil War.

Although some of the Civil War’s public health lessons became mainstream practices in the 20th century, the sense of urgency the Civil War generation felt about public health has fallen by the wayside.

Had the lessons they learned remained fresh in our collective historical consciousness, the U.S. might have applied them and fared better during the time of Covid-19. Instead, we forgot about medical history, and as a result, we’ve endured the worst public health crisis in generations.

Jonathan S. Jones is a historian and postdoctoral scholar at Penn State University’s George and Ann Richards Civil War Era Center.

Hear Jones talk more about the Civil War on an episode of the “First Opinion Podcast.”