Pasteur, Louis

PASTEUR, LOUIS. - Born at Dôle on 27 Dec. 1822, died at Villeneuve-l'Etang on 28 Sept. 1895. He obtained the baccalaureate in letters (1840) at Besançon and in mathematics (1842) at Dijon. In 1843 he was appointed assistant in chemistry at the École Normale and in 1848 he was called as substitute to the chair of chemistry at the University of Strasbourg, where he subsequently became full professor (1852); in 1854 he was dean of the Faculty of Sciences at Lille. He was elected a member of the Académie de médecine (1873) and of the Académie française (1882); he was esteemed, admired and honored by his contemporaries (Darwin, Bentham, Milne Edwards, Claude Bernard, etc.). He was a fine soul of a believer in an age of materialistic and positivistic science.

He began his research in crystallographic chemistry (1843), establishing the relations between the crystalline form of bodies and their optical properties; this research led him to the study of the chemistry of fermentations (1848-1877), in which he established that every type of fermentation is the work of special living microorganisms (ferments); studying the origin of ferments, P. found himself confronting the problem of spontaneous generation: with ingeniously devised and brilliantly executed experiments, he demonstrated that microorganisms can only come from microorganisms present in the environment; following the bitter controversy aroused by his experiments (especially by the interpretation given to them by Charlton Bastian, an English supporter of spontaneous generation), P. tackled the problem of the destruction of germs by heat, discovering the methods of sterilization and asepsis. On assignment from the French government he studied the disease of the silkworm (pebrine) and laid down rules for combating and preventing the scourge (1865). In the field of the etiology of infectious diseases, although preceded by Davaine and by Koch, he won glory and popularity by discovering the pyogenic streptococcus (agent of puerperal fever) in 1878, and by indicating the means to prevent its infections; chicken cholera (1875), swine erysipelas (1801), etc. Studying anthrax (1877), moreover, he discovered that the inoculation of weakly virulent microbes into the animal organism causes a benign disease that immunizes against the malignant morbid form of the virulent germs; P., by giving a rational basis to the principle of vaccination, already applied empirically by Jenner and by others, made possible its generalization and dissemination; together with his collaborator Roux he prepared vaccines against chicken cholera, against anthrax (1881) and against rabies (1882).

In Paris he founded the "Institut P.", a famous laboratory in which valuable research in the field of the biological sciences and of serotherapy continues to be carried out. The works of P. were collected all together (Oeuvres de P., Paris 1922).

Giorgio M. Baffoni