Louis Pasteur: The Father of Microbiology | Heroes of Progress

Louis Pasteur, dubbed the Father of Microbiology, was born to a poor French family in 1822. At 17, Pasteur earned a Bachelor of Letters after only one year at the Royal College of Besançon. He then continued his studies, eventually becoming a chemistry professor at the University of Strasbourg in 1848. There, Pasteur met his wife Marie. The pair had five children but lost three to typhoid. Some say their deaths motivated Pasteur to study infections and vaccinations. In 1856, while investigating alcohol fermentation, Pasteur discovered key evidence supporting the germ theory of disease. After nothing grew in broth sealed off from its surroundings, Pasteur concluded that pathogens must enter organisms from the outside, not from within. In the process, he found that heating liquids killed the bacteria inside, a technique now known as pasteurization. Pasteur then turned his attention to vaccines. After countless experiments injecting chickens with a cholera-causing bacterium, Pasteur became the first scientist to use an artificially weakened pathogen as a successful vaccine. In 1881, he developed a vaccine for anthrax and, four years later, for rabies. By 1888, he received enough donations to open the Pasteur Institute, dedicated to studying biology, microorganisms, diseases, and vaccines. Louis Pasteur's work changed the world. His proof for the germ theory of disease revolutionized the way we think about human health. Pasteurization enabled us to preserve beverages and canned foods far longer than thought possible, and his experiments paved the way for future vaccines. Without him, hundreds of millions, if not billions, of people would not be alive today. For that reason, Louis Pasteur is our 19th Hero of Progress.