PASTEUR, LOUIS. — Born in Dôle on 27 Dec. 1822, died at Villeneuve-l’Étang 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 professor 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 noble soul of a believer in an age of materialistic and positivistic science.
He began his research in crystallographic chemistry (1843), establishing the relationships between the crystalline form of substances and their optical properties; these studies led him to investigate the chemistry of fermentation (1848–1877), in which he established that each type of fermentation is the work of special living microorganisms (ferments). In studying the origin of ferments, Pasteur found himself confronting the problem of spontaneous generation: through ingeniously designed and brilliantly executed experiments, he demonstrated that microorganisms can only arise from microorganisms already present in the environment. Following the heated controversy aroused by his experiments (especially the interpretation given by Charlton Bastian, an English advocate of spontaneous generation), Pasteur addressed the problem of destroying germs by heat, discovering methods of sterilization and asepsis. At the request of the French government, he studied the silkworm disease (pebrine) and laid down rules to combat and prevent the scourge (1865). In the field of the etiology of infectious diseases, though preceded by Davaine and Koch, he won fame and renown by discovering the streptococcus pyogenes (the agent of puerperal fever) in 1878 and by indicating means to prevent its infections; the fowl cholera (1875), swine erysipelas (1881), etc. In studying anthrax (1877), he also discovered that the inoculation of weakly virulent microbes into an animal organism provokes a mild disease that provides immunity against the malignant form caused by virulent germs. By giving a rational basis to the principle of vaccination, already applied empirically by Jenner and others, he enabled its generalization and dissemination; together with his collaborator Roux, he prepared vaccines against fowl cholera, anthrax (1881), and rabies (1882).
In Paris he founded the Institut Pasteur, a renowned laboratory where valuable research is carried out in the fields of biological sciences and serotherapy. Pasteur’s works were collected in a single edition (Oeuvres de P., Paris 1922).