False-colour transmission electron micrograph (TEM) of the Gram-negative bacterium Vibrio cholerae, the cause of cholera in humans. The comma-shaped bacterium moves using its tail-like flagellum. Cholera is an acute infection of the small intestines causing vomiting & diarrhoea leading to rapid & potentially fatal dehydration. The bacterium is a water borne pathogen, transmitted to humans through drinking water contaminated by human or animal faeces. Outbreaks of cholera are associated with poor sanitary conditions & often occurs in epidemic proportions. Magnification: x6,000 at 35mm size.