Free Allies and Enemies: How the World Depends on Bacteria by Anne Maczulak Page B

cultivated the ability (or flaw according to some) of drawing scientific conclusions even while producing little data to back them. Louis Pasteur possessed such a rare and keen insight into biology that his conclusions almost
    always proved to be correct. One famous misstep occurred in 1865
    during a cholera outbreak in Paris. Pasteur believed the pathogen Vibrio cholerae transmitted through the air though it is a waterborne pathogen. The French nonetheless felt relieved to know that Pasteur was hard at work trying to save them from cholera. The Paris epidemic
    ran its course and disappeared on its own.
    During a rabies scare in 1885, Pasteur concocted a treatment and
    gave the untested drug to a nine-year-old boy, Joseph Meister, who
    had been bitten by a grocer’s dog. Three weeks later, Meister had almost fully recovered. Pasteur’s legend received considerable help by the fact that Meister hailed from Alsace, a region controlled by Germany but claimed by France. The tricolor declared a victory for French science and for Pasteur who had beaten the German, Robert
     
    Koch, who had like Pasteur been working on vaccines. As a grown man, Joseph Meister took a job as a guard at the Institut Pasteur after Pasteur’s death. When German troops entered Paris in 1940, they swarmed the institute’s grounds and ordered that Pasteur’s crypt be opened. Meister likely had been one of several men who defended
    the crypt against the Wehrmacht and prevented its defilement.
    Shortly after, Meister inexplicably shot himself through the head.
    Even this act became part of Pasteur’s celebrity. Historians would write that Meister committed suicide in front of the Germans rather than disturb Louis Pasteur, France’s hero.
    Pasteur’s influence on microbiology cannot be captured in a few
    pages. Early in his career, Pasteur had disproved the long-held theory
    of spontaneous generation, the belief that microbes and all other life
    arose from inanimate things: rocks, water, or soil. Biologists had already begun taking sides on this issue prior to Pasteur. As their science matured, many microbiologists doubted the logic behind spontaneous generation—science was increasingly distancing itself from spiritual dogma. Pasteur developed an experiment that unequivocally showed that a flask of sterilized broth could not produce life on its
     

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    allies and enemies
    own. Pasteur modified this flask with an S-shaped tube to serve as the
    opening. This configuration let in air but prevented any particles from the air to enter. A second sterile flask left open to the air was soon teeming with bacteria but the S-flask remained sterile. Elegant
    in its simplicity, Pasteur’s experiment earned him respect from his contemporaries.
    During his career, Pasteur also distinguished between anaerobic
    and aerobic metabolism, invented the preservative method to be
    known as pasteurization, and developed the first rabies and anthrax
    vaccines (see Figure 2.3). As a postscript, the original S-flask is on display at the Institut Pasteur today and remains sterile.
     
    Figure 2.3 Bacillus anthracis, the anthrax pathogen. B. anthracis and all other Bacillus species form a tough, protective endospore. In this picture, endospores in phase-contrast microscopy look like bright ovoid balls inside an elongated cell. (Courtesy of Larry Stauffer, Oregon State Public Health Laboratory)
    chapter 2 · bacteria in history
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    When bubonic plague erupted in Asia in the late 1800s, Pasteur
    dispatched Alexandre Yersin of the French Colonial Health Service
    to investigate. Microbiologists had by that time a century of using ever-improved microscopes, and they had become skilled at diagnosing disease by examining patient specimens to detect pathogens. In 1894, Yersin and a bacteriologist sent by Japan’s government, Shibasaburo Kitasato, rushed with other public health officials to Hong Kong where a localized plague outbreak was emerging. Within a week Yersin isolated a