“Playing Old Soldier” by Winslow Homer — this boy is faking it, but for many tens of thousands of Civil War soldiers, illness was all too real. (Boston Museum of Fine Arts)

Measles was typically the first disease to rip through Civil War encampments, as country boys were exposed to diseases they never saw at home. Then diarrhea and dysentery took hold as a result of rather casual sanitary arrangements. Something like ten percent of such cases in the Confederate army ended in death, and many other soldiers were left permanently weakened by persistent gastrointestinal maladies. Federal soldiers called diarrhea “the quickstep.” Malaria was also a problem, particularly along the seacoasts. Typhoid fever from bad water was a constant menace. Robert E. Lee’s army suffered a virulent outbreak of smallpox in late 1862.

On the whole, I’d guess that diarrhea was the single most prevalent disease among soldiers on both sides in the war.

Many more men, on both sides, died of disease than battle.

War is hell.