Keeping soldiers encamped for extended periods exposed them to numerous camp illnesses. So devastating were these sicknesses that for every soldier that perished in action two died behind the lines from sickness. The most common illness was dysentery, an infectious disease marked by severe diarrhea. One million cases were reported among the two million soldiers of the Union armies; the statistics were as bad or worse for the Confederates.
A variety of medicines were prescribed, with the most common being a mixture of opium and castor oil. Few of these remedies did any good. Typhoid, malaria, and measles also took their toll. No wonder soldiers uniformly agreed that “it scares a man to get sick.” It was, ironically, often safer in combat rather than in camp situations for the average soldier.