Illustration of the intestines and mesentery removed from a patient who died of cholera. The mesentery is a membrane that attaches several abdominal organs, including the intestines, to the back wall of the abdomen. Cholera, a bacterial infection of the intestines, was often fatal before modern treatments were developed. It spread in infected water supplies and killed millions in the 19th century. The bacterium causing the disease (Vibrio cholerae) was not identified until 1883. From Illustrations of pathological anatomy by Alfred Kast and Theodor Rumpel (1892-1895).