The first link shows electron micrographs of Vibrio Cholera and information
about the organism. In addition to discovering the causative organism for
cholera, Koch also discovered the causative organisms for tuberculosis and
anthrax. His achievements were so well recognised they were even celebrated on
Chocolate boxes! (see second link). However, even though the causative organism
was not known prior to Koch, John Snow’s epidemiological work allowed
preventative action to be taken saving many many thousands of lives.