Germ theory and its applications to medicine & on the antiseptic principle of the practice of surgery - Louis Pasteur

Before the introduction of antisepsis and inoculation, people commonly died due to unsanitary conditions in the home, or following surgery or childbirth. Between them, the great scientists Louis Pasteur (1822-1893) and Joseph Lister (1827-1912) extended widely the practice of inoculation and revolutionized medical practice. Pasteur's discovery that living organisms are the cause of fermentation formed the basis of the modern germ theory. Following Pasteur's researches, Lister proceeded to develop his antiseptic surgical methods. These breakthroughs in medicine are to be reckoned among the greatest discoveries of the nineteenth century.