A copyrighted photograph of ‘The common bacillus of Asiatic cholera’ 5th April 1886, Catalogue ref: COPY 1/376/22
In 1883 a German doctor, Robert Koch, building on the important earlier work of Louis Pasteur, identified the bacterial causes of cholera (Vibrio cholera) with a microscope and theories about ‘miasma’ were replaced in medical thinking by ‘germ theory’.