As U.S. COVID-19 Deaths Top the Civil War’s Toll, We’re Repeating Disease History

On Saturday, the United States passed a new landmark in the fight against the novel coronavirus, when the death toll surpassed 620,000 people, the classic estimate for the number of deaths from the American Civil War. The grim comparison is telling, not only because of the sheer size of the death toll, but also because it carries a bleak secondary meaning.

The Civil War, infamous for having the highest American death toll of any war in history, was the last major American conflict before the greater public understood how diseases spread. It was therefore the last war where the bulk of the deaths—two-thirds, in fact—were not from bullets and bombs, but from viruses, parasites and bacteria. Unfortunately, today’s COVID-19 death toll shows that many have approached the virus with a medical attitude hardly updated from 160 years ago.

The impact of disease on the course of the Civil War began almost as soon as the conflict was sparked. Both Union and Confederate soldiers found themselves caked in mud and sleeping in tents in improvised encampments. Without knowledge of how diseases spread, these close quarters encouraged bacteria and viruses to run rampant through the ranks.

Measles, mumps, whooping cough and chickenpox ravaged the troops first while in training camps, spreading via exhaled respiratory droplets and aerosols from one soldier to the next as the germs found new paradise in the bodies of countrymen whose rural lives had largely isolated them from previous exposure. When the new soldiers finished training, they joined the armies in the field, where the so-called “camp diseases” of pneumonia, smallpox and the skin infection erysipelas quickly mounted a second wave of assault.

“Theoretically, all recruits were to be vaccinated [for smallpox] coming into the army,” says Robert Hicks, PhD, former director of the Mütter Museum of The College of Physicians of Philadelphia and an expert in Civil War medical history. But in practice, he says, “that simply didn’t happen.” The Union enacted a blockade of all Southern ports early in the war, which limited the Confederates’ ability to import medical supplies. However, because every person at that time had an understanding of the power of disease, unprotected troops engaged in desperate attempts at home self-innoculations using pus from the oozing sores of infected friends and neighbors.

The other pathogens, completely unchecked by science, hit the soldiers with such rampant rates of spread that even the germs with low fatality percentages racked up impressive total body counts.

Lice, which spread typhus, were endemic, but perhaps the most infamous and preventable infections and diseases of the time were dysentery and typhoid fever. According to the accounts of both Union and Confederate officers, soldiers were resistant to even what little information the time period could provide about hygiene and sanitary practices. Confederate General Robert E. Lee tried without success to get his soldiers to bathe regularly to limit the spread of lice, but he recorded that soldiers were “worse than children [at keeping clean], for the latter can be forced.”

As the years of the epically miserable war ticked by, weary soldiers increasingly took to defecating wherever convenient in their camps. Without knowledge of the basics of germ theory, they routinely relieved themselves in their own water supplies. One army surgeon at the Battle of Vicksburg said that by late 1863, the soldiers had given up so much on basic hygiene that “human excrement has been promiscuously deposited in every direction.” This pattern caused regular outbreaks of dysentery, cholera and typhoid fever that sparked cliches still in use today: the troops most susceptible to these diarrhea-inducing ailments were said not to have the “guts” for soldiering.

Of the 349,944 enlisted Union soldiers who were killed in the war, 221,791 (63%) died of infectious diseases, not including gangrene from battle wounds. But even the simplest of adjustments to personal hygiene proved effective.

Robert Hicks, a former U.S. Navy officer himself, explains how the officers could essentially socially distance, as “they could frequently choose their messmate and essentially, their tent mate. They were allowed far more personal space for living conditions.” Fewer officers died of dysentery because they were in less crowded encampments, had access to cleaner water and, at least according to their own accounts, had better hygiene. Only 29% of the officers who died were killed by disease.

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Then, as now, health measures worked, but only for those both willing and able to take them. Today, high mask use has repeatedly shown to be a factor in decreasing community mortality rates from COVID-19—but masks only make a difference if you wear them. And, with the availability of vaccines, many news sources are now quipping that this has become a “pandemic of the unvaccinated.” The soldiers of the Civil War may not have had sufficient scientific knowledge to stop their myriad plagues, but modern Americans have no excuse for achieving our current rate of disease-induced fatalities.

But, while the American Civil War raged, and the invisible “Third Army” of viruses and bacteria stacked the bodies like cordwood for both sides, Louis Pasteur was also figuring out how to stop it. By the late 1800s, his pasteurization process would not only make milk safer, but also emphasize why future troops needed to boil potentially contaminated water before drinking. By 1885, Pasteur would take his ideas one step further, injecting slurried concoctions containing attenuated rabies virus into the stomach of a young boy to save the boy’s life, and inventing the first lab-made vaccine. Using Pasteur’s methods, by 1896 there were also vaccines for typhoid and cholera, and by 1897, the plague fell too. By WWI, these ground-breaking discoveries formed a far more powerful medical arsenal with which armies could attack how diseases spread within troop encampments. The numbers prove the efficacy. During the winter of 1914-1915, the French Army experienced 11,000 deaths from typhoid in the cold, densely populated, mud-filled trenches that characterized that war. But after implementation of a typhoid vaccination program, by 1917-1918, the same army had only 615 cases of typhoid. Meanwhile, without a flu vaccine, the 1918 influenza pandemic became the only mass event in American history to outstrip the Civil War in terms of deaths—until now.

At the onset of the Civil War, South Carolina senator James Chestnut bragged proudly that he would drink every drop of blood spilled as a result of secession, because he was so baselessly confident there would be none. Not only did the war drag on for four miserable years, but frequently, the largely unmitigated spread of infectious diseases caused such high rates of attrition that both armies had to delay or change their battle plans, lengthening the war by an estimated two years.

Again, the declarations of today’s politicians are all too often woefully unfounded. And in an eerie historical parallel, because so many have chosen to willfully ignore the accomplishments and discoveries of the scientists of the late 1800s, we have pushed ourselves back to the disease-spread patterns of the Civil War and lengthened our own war against this inanimate virus by an incalculable amount.

Recent academic research has suggested that the human toll of the four-year Civil War may have been even greater than the 620,000 that has so long been cited. Perhaps as many as 513 people died, on average, each day, for a total closer to 750,000. Even though we have 160 more years of medical and scientific knowledge, the refusal of some Americans to accept any of the multiple available measures against disease spread has forced us to an average death rate of 1,200 per day over the first 17 months of the pandemic. As of today, in its battle against disease, America has not only repeated history, but surpassed it.

Historians’ perspectives on how the past informs the present

Rachel Lance, PhD, is a biomedical engineer and the author of In the Waves: My Quest to Solve the Mystery of a Civil War Submarine