Cholera is a severe bacterial infection caused by the bacteria Vibrio cholerae, which primarily affects the small intestine and the main symptoms include production of profuse watery diarrhea and vomiting. Transmission is primarily by the acquisition of the pathogen through contaminated drinking water or infected food. The severity of the diarrhea and associated vomiting can lead to rapid dehydration (hypohydration) and electrolyte loss. If these are not replaced then death may follow. Cholera likely has its origins in and is endemic to the Indian subcontinent. The disease spread by trade routes (land and sea) to Russia, then to Western Europe, and from Europe to North America. Cholera is now no longer considered a pressing health threat in Europe and North America due to filtering and chlorination of water supplies, but still heavily affects populations in developing countries.