As etiologic concepts of diseases gradually changed from humoral to microbial in the 19th century, syphilis presented particularly great challenges to doctors and scientists. Was “syphilis” merely a synonym for “venereal disease,” and did all manifestations attributed to it have the same cause? The discovery in 1879 of the gonococcus by Albert L. Neisser , and of the cause of chancroid, or soft chancre, in 1890 by Augusto Ducrey , established that venereal disease and syphilis were not synonymous, but syphilis (...) continued to mystify investigators. Symptoms could disappear for years and then—in most but not all persons—reappear with entirely different “tertiary” manifestations. .. (shrink)

The ability to effectively prevent smallpox was the greatest medical accomplishment of the first half of the 19th century. From 1838 to 1840, half a century after vaccination was introduced but before it became mandatory in England, data about the general population of England and Wales recorded 70 deaths per million from smallpox; only 180, 900 vaccinations were recorded. In London alone from 1848 to 1852, there were 4, 858 youthful deaths from smallpox, 67% of which occurred during the first (...) five years of life (Simon 1857).In a report to the House of Commons in 1802, Edward Jenner (1749-1823) stated that person-to-person vaccination was a basic principle of his procedure. He gained confidence in it from the case .. (shrink)