20 incredible years that revolutionised our understanding of disease. From Hippocrates to Louis Pasteur, the medical profession relied on almost wholly mistaken ideas concerning infectious illness. Bleeding, purging and mysterious nostrums remained staple remedies. Surgeons, often wearing butcher's aprons caked in surgical detritus, blithely spread infection from patient to patient. Then, between 1879 and 1900, came the germ revolution. Scientific virtuosity, outstanding intellectual courage and bitter personal rivalries characterised this breathtaking rapid sea-change in scientific thinking.