Casimir Davaine (1812-1882): a precursor of Pasteur.

SEVERAL centuries before Pasteur's epoch-making discoveries, physicians and naturalists had suspected that certain contagious diseases in man and in domestic animals were caused by parasites invisible to the naked eye (this was named the 'contagium vivum' theory).' Those views, at first purely theoretical, were confirmed in 1687 when two pupils of Francesco Redi: Bonomo and Cestoni proved that human scabies was caused by a tiny parasitic mite (nowadays known as Sarcoptes scabiei) which they were able to isolate and describe, thanks to the recently invented microscope. A century and a half later, in 1835, Agostino Bassi (1773-1856), another Italian scientist, proved that another disease, silk-worm rot, is caused by a fungous parasite, which was named after him, Beauveria bassiana.2 In 1836-7, Alfred Donne isolated and described Trichomonas vaginalis, the vaginal Flagellate found in women;3 and, between 1841 and 1844, David Gruby (1810-1898) isolated the fungi responsible for the most common human mycoses. He also discovered and described, in 1843-44, a new protozoon which he called 'trypanosome' in the frog.' Thus, up till this time, only protozoa and multicellular organisms such as one acarian and fungi, were recognized as playing a pathogenic role. From 1676 on, certain bacteria had been observed and described by the well-known Dutch microscopist Anthony van Leeuwenhoek (1632-1723) but he was concerned only with non-pathogenic species which he found in vegetable or animal infusions or in dental tartar. Other free living bacteria were described during the eighteenth and nineteenth centuries. The credit of demonstrating for the first time the pathogenic role of a bacterium in the human being and in domestic animals goes to the little-known French physician Casimir Davaine (1812-1882), whose bacteriological work is the main topic of this paper. First of all, a few words on the man. The sixth of the nine children of a distiller at St. Amand-les-Eaux, in the North of France, Casimir-Joseph Davaine was born on 19 March, 1812. He began his studies at St. Amand, continued at Tournai and Lille, and in 1830 he registered at the Faculty of Medicine of Paris. * This is the text of a lecture given on 10 May 1965 at the Wellcome Historical Medical Library, London. It constitutes an abridged version of a lecture given in Paris in 1963 and published under the title 'Casimir Davaine et les d6buts de la Bact6riologie m6dicale', Confs Palais D&ouv., 1964, No. 95., pp. 32. The author wishes to thank Miss J. Lawson, Dr. J. Schiller, and Dr. F. N. L. Poynter, who have helped him in his translation.