Pasteur Proves Germ Theory — Founding of Microbiology
Louis Pasteur showed in 1861 that microorganisms come from other microorganisms and not from nothing, and modern medicine follows from it. Spontaneous generation was a respectable position with a long history: broth left out fills with organisms, so the organisms must arise from the broth. The experiment that settled it used a flask with a long neck drawn out into an S-shaped curve. Boiled broth in such a flask stayed clear indefinitely, because dust and spores settled in the bend and could not reach the liquid, and air could. Tilt the flask so that the broth touched the bend and it spoiled within days. The French Academy had offered a prize on the question, and Pasteur's flasks — some of which are still clear in Paris — took it. He had come to it through commercial problems. Wine and beer that soured, and silkworms that died, both turned out to be microbial, and his answer to the first was gentle heating, which took his name. The application to medicine was made most directly by Joseph Lister in Glasgow, who read Pasteur and began treating wounds and instruments with carbolic acid in 1867, cutting amputation mortality dramatically at a time when a surgeon's frock coat was stiff with old blood. Pasteur later developed vaccines for anthrax and rabies, giving the first rabies inoculation to a mauled nine-year-old boy in 1885 without a medical licence. Robert Koch in Germany supplied the criteria for proving that a specific organism causes a specific disease. The resistance to all of this was considerable and lasted decades, because it required doctors to accept that they had been carrying disease from patient to patient on their hands. Ignaz Semmelweis had demonstrated the point in a Vienna maternity ward in 1847, was ignored and dismissed, and died in an asylum the year before Lister began.
- Year: 1861 CE
- Category: Scientific
