These were caused by enterotoxin-producing strains of the bacterium Vibrio cholerae. Although the contamination of the water supply was correctly diagnosed by Dr John Snow in 1849 as the method of communication, up to the outbreak of 1866 it was believed that miasma, or bad air, was responsible.
Proposals to modernise the sewerage system had been made in the early 1700s but the costs of such a project deterred progress. Further proposals followed in 1856, but were again neglected due to the costs. However, after the Great Stink



