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It was the height of the 19th century, the dawn of medical and biological science as we know it. The process of discovering everything that is now easily found in text book was lengthy and often much less sanitary than its modern counterpart. Though the several of the basic techniques of modern science had been laid out before 1856, a scientific paradigm as we know it had not yet gained complete dominance. The second half of the 19th century was wrought with odd combinations of science and fantasy. Many people still believed in spontaneous generation -- that flies, maggot, microbes, formed out of nothing, or out of inert matter -- and Felix Pouchet even claimed to have scientific proof of it.
One of the most famous and yet oddest tales of microbiological advance is the story of the violent and obsessive competition between France and Germany played out by Louis Pasteur (1822 - 1892) and Robert Koch (1843-1910) in an era of increasing nationalism. Pasteur was a French Chemist and Koch was a German doctor, a student of Jacob Henle, who'd come up with a theory of how disease spreads.
Henle believed that the agents that caused disease in animals, plants and humans were tiny living organisms. He had a list of rules about how to establish which microscopic organism caused which disease. The organism had to be consistently found alongside the specific illness, and it had to be "isolated" from the flesh of the sick animal or person. Thereafter, the isolated organism had to cause the disease on its own. For example, if a cow was sick with a disease of the blood, to prove Henle's postulates, a veterinarian would take a sample of the cow's blood and look under a microscope for bacteria or viruses. Once the veterinarian found one or more, they would isolate the bacteria from the rest of the material in the cow blood, and then inject it into a healthy cow. If they cow manifested the same disease as the first cow, they could be certain that what they had isolated was the causative agent.
Both Pasteur and Koch were familiar with Henle's work, though only Koch studied under him. Pasteur was roughly twenty years older than Koch, and because of this, he was able to make huge leaps in the field of microbiology and medicine before Koch was active in the field. He got quite a head start on amassing "victories" in the Franco-German microbial wars.
In 1856, Pasteur began solving domestic French agriculture and production problems. He discovered that beet juice fermentation and grape fermentation were entirely different, one was cause by a bacterium, and the other by a fungus, yeast. He isolated both the yeast and the bacterium and showed what each could do.
Five years later, Pasteur decided to tackle the issue of spontaneous generation, which he staunchly opposed. He created a famous proof against the theory of spontaneous generation. Pouchet believed that though creatures sprung up from nothing, they required the presence of oxygen, so cutting them off in a closed flask would keep them from doing so. Pasteur believed microscopic organisms, or microbes, were present in the air, and that leaving a flask open to the air would not produce spontaneous generation, but would produce contamination of the flask: organisms that existed in the air, or on the biologist's hands, would fall into the flask and begin living there.
Pasteur thought of an ingenious way to disprove Pouchet using swan-necked flasks. Pasteur set out two rows of flasks, one set were normal, with open tops, the set had curved, s-shaped tops, with the mouth finally pointing down. The normal flasks produced Pouchet's "spontaneous generation" effects, but the swan-necked flasks did not, even though they had the same access to oxygen. Pasteur argued that the microbes had been trapped in the S of the swan-neck, and could not reach the nutrients that had been placed inside the flask, though air particles could. The Pouchet-like effect in the first set of flasks was a result of contamination.
In 1863, French wine-makers were suffering from tons of barrels of spoiled wine. Again, in a rage of nationalism, Pasteur decided to solve their problem for them. He studied the "diseases" of the bad wine and could eventually tell by looking at wine samples under a microscope whether or not they were good, how they would taste, and what was wrong with them if they'd gone bad. He noticed that good wine didn't contain any bacteria to speak of, but the different diseases of wine were all associated with different bacteria. In response to this, he developed a process of slow heating the wine at 63 degrees centigrade for 30 minutes. The process is called Batch Pasteurization and was immediately adopted by France and the burgeoning wine industry of California. Batch Pasteurization is hardly used for wine in the 20th century, as a better method that is less damaging to the flavor of the wine has been invented.
It didn't take Pasteur long to wonder: If different microbes cause different diseases in wine, maybe they cause specific diseases in humans as well. This theory had already been touched upon by Henle, but Pasteur set about testing it.
Meanwhile, one of the Henle's own students was forced to move the country with his new wife, whom he disliked. She gave him one of the best microscopes on the market in 1872 as a peace offering. Koch continued to ignore his wife, and began looking at everything under his Zeiss Microscope. Living in the country he came in contact with anthrax, a common disease of livestock and people. He found bacteria in the blood of sheep who died of Anthrax, and never found it in the blood of healthy sheep. To test his mentor's theory, he inoculated mice with anthrax using infected sheep's blood and found to his delight, the mice died of anthrax.
In the process of infecting various animals with anthrax to see how it spread, Koch came up against the problem of how to breed bacteria outside of host bodies. He needed to find some kind of medium on which he could contain and grow deadly bacteria. In the beginning, he used the vitreous tissue from sheep's eyes, but eventually he was to perfect the modern technique of "pure culture." In modern labs, microbiologists store microbes on a sterilized medium called "agar" which can be brought to a boil to kill anything already living in it, before microbes are introduced. One of the best things about agar is that it stays gelatinous at body temperature. Koch saw the need for such a thing, but didn't have access to it. He tried all kinds of growth mediums and nutrient baths for his samples, but it was only when a friend of his wife mentioned that she used "agar agar" to make her jellies and jams more solid in summer that he had what he needed. Koch's lab assistant eventually designed specialized dishes to contain the samples, so that they would be easy to work with. These are still used today and called Petri dishes.
Pasteur heard of Koch's work when it became famous in scientific journals and Germany was pushed to the forefront of microbiology. Pasteur was determined to the win the title back for France, and began making a study of another disease that affected French agriculture and livestock: chicken cholera. His work got him nowhere, until he accidentally left a culture of it out over vacation in the summer heat, and came back to discover that this particular batch of cholera only gave chickens a very mild case of the disease which did not kill them. Pasteur realized the microbe in question had become "heat-attenuated" or weakened by the heat, but that once a chicken caught the disease, even a mild case, it was immune to more severe infections. Pasteur quickly created deliberately attenuated batches of virus and gave it to the chickens as a vaccine.
In 1880, when his work with chickens was quite concluded, Pasteur wanted to smite Koch more completely. He decided to make an anthrax vaccine, assuming it would work much the same as chicken cholera had. Although it turned out anthrax could not be heat attenuated, Pasteur did eventually find a way to create a vaccine-worthy form of it, and began administering it left and right in France.
Koch was disgusted with Pasteur's accomplishment, and decided the only way to win international favor back for himself and Germany was to turn to one of the most serious social problems of the time: the human disease tuberculosis (TB), "the great white plague." He cultured TB out of human blood and used his sample to infect mice. He proved the world's watching eyes that human disease worked the same way as animal and wine disease, by infection with a microbe. In 1884, riding a wave of acclaim, Koch published his own modified version of Henle's postulates, requiring an additional step than Henle had not.
The next year Pasteur decided he could also solve problems of human disease, and tried to find a vaccine for rabies. Very few humans were struck with rabies every year, unlike tuberculosis, but the disease had a disgusting and wild course, driving the infect insane. Every time someone in Europe was infected with it, every paper on the continent carried stories about it. Pasteur was after headline, so he targeted rabies. Heat attenuation didn't work on rabies virus, but Pasteur eventually discovered that desiccation -- or attenuation by removal of all water -- did. He realized that rabies was an unusual microbe, but he never realized that it was a virus, though he developed a successful vaccine for it. Impressed newspapers helped set up funds for Pasteur's research. Pasteur turned around and set up the Pasteur Institute in Paris, which is still at the forefront of microbiological research and medical science to this day. Pasteur retired in glory.
Koch found himself under immense pressure from the German press and scientific community to outperform Pasteur and show German superiority once and for all. At the 10th International Medical Conference in Berlin, Koch felt forced to announce good news that he really didn't have. He said he'd found a cure for tuberculosis, called "Tuberculin" but he knew he had no such thing. All tuberculin really was isolated TB, but Koch didn't want to admit his failure and so administered tuberculin to hundreds of people who developed TB and died. In the midst of public scandal, Koch fled Germany for Africa with his young mistress.
Sadly, the word on the scandal never reached the entire populace. The next year, the German government began its Institute for Infection Disease, sometimes called the Koch institute. But this fell apart within a couple years when the scientists and doctors involved began squabbling over royalties for discoveries.
In 1905, Koch actually received the Nobel Prize for the discovery of tuberculin, though it killed hundreds of people and was no cure at all. This mistake has never been corrected, perhaps due to embarrassment.
Though Koch's career ended very poorly, the rivalry between Pasteur and Koch produced a method for making vaccines, a method for obtaining pure cultures, and essentially proved what had before been a theory: that microbes caused disease.