Doctors investigating cholera. 19th-century illustration of doctors from the London Board of Health looking for signs of cholera. 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. This caricature, by British artist Robert Seymour (1798-1836), was published in the 1 March 1832 edition of the London magazine 'McLean's monthly sheet of caricatures'.