Cholera is an intestinal infection caused by a bacterium, called Vibrio cholerae. The infection turned lethal when it first appeared in Europe and North America in the 19th century, when the epidemic killed thousands of people because scientists at the time did not realize that the bacteria spread through contaminated drinking water until 1855.
Cholera causes intense watery diarrhea, vomiting, and leg cramps. Cause of death from cholera occurs from an excessive, overwhelming loss of body fluids. In the 19th century, because scientists didn't know that the contaminated drinking water was the root of infection, people suffering from severe cholera were given more of the water that made them sick. Now that scientists understand the cause of the disease, it can be cured with simple fluids.