Deaths from cholera in London. 19th-century plan showing the ascertained deaths from cholera in part of the parishes of St James, Westminster, and St Anne, Soho, during the summer and autumn of 1854. The diagram shows the old and new sewers and numbers of deaths (key at lower right). This was part of a report prepared and published by the Cholera Inquiry Committee in July 1855. 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.