Robert Koch Biography (1843-1910)
Robert Koch is considered to be one of the founders of the field of bacteriology. He pioneered principles and techniques in studying bacteria and discovered the specific agents that cause tuberculosis, cholera, and anthrax. For this he is also regarded as a founder of public health, aiding legislation and changing prevailing attitudes about hygiene to prevent the spread of various infectious diseases. For his work on tuberculosis,he was awarded the Nobel Prize in 1905.
Robert Heinrich Hermann Koch was born in a small town near Klausthal, Hanover, Germany, on December 11, 1843, to Hermann Koch, an administrator in the local mines, and Mathilde Julie Henriette Biewend, a daughter of a mine inspector. The Koch's had a total of thirteen children, two of whom died in infancy.Robert was the third son. Both parents were industrious and ambitious. Robert's father rose in the ranks of the mining industry, becoming the overseer ofall the local mines. His mother passed her love of nature on to Robert who, at an early age, collected various plants and insects.
Before starting primary school in 1848, Robert taught himself to read and write. At the top of his class during his early school years, he had to repeat his final year. Nevertheless, he graduated in 1862 with good marks in the sciences and mathematics. A university education became available to Robert whenhis father was once again promoted and the family's finances improved. Robertdecided to study natural sciences at Gottingen University, close to his home.
After two semesters, Koch transferred his field of study to medicine. He haddreams of becoming a physician on a ship. His father had traveled widely in Europe and passed a desire for travel on to his son. Although bacteriology wasnot taught then at the University, Koch would later credit his interest in that field to Jacob Henle , an anatomist who had published a theory of contagion in 1840. Many ideas about contagious diseases, particularly those of chemist and microbiologist Louis Pasteur , who was challenging the prevailing mythof spontaneous generation, were still being debated in universities in the 1860s.
During Koch's fifth semester at medical school, Henle recruited him to participate in a research project on the structure of uterine nerves. The resultingessay won first prize. It was dedicated to his father and bore the Latin motto, Nunquam Otiosus, or Never idle. During his sixth semester, he assisted Georg Meissner at the Physiological Institute. There he studied the secretion of succinic acid in animals fed only on fat. Koch decided to experiment on himself, eating a half pound of butter each day. After five days, however, he was so sick that he limited his study to animals. The findings of this study eventually became Koch's dissertation. In January 1866, he finished the final exams for medical school and graduated with highest distinction.
After finishing medical school, Koch held various positions; he worked as anassistant at a hospital in Hamburg, where he became familiar with cholera, and also as an assistant at a hospital for retarded children. In addition, he made several attempts to establish a private practice. In July, 1867, he married Emmy Adolfine Josephine Fraatz, a daughter of an official in his hometown.Their only child, Gertrude, was born in 1868. Koch finally succeeded in establishing a practice in the small town of Rakwitz where he settled with his family.
Shortly after moving to Rakwitz, the Franco-Prussian War broke out and Koch volunteered as a field hospital physician. In 1871, the citizens of Rakwitz petitioned Koch to return to their town. He responded, leaving the army to resume his practice, but he didn't stay long. He soon took the exams to qualify for district medical officer and in August 1872 was appointed to a vacant position at Wollstein, a small town near the Polish border.
It was here that Koch's ambitions were finally able to flourish. Though he continued to see patients, Koch converted part of his office into a laboratory.He obtained a microscope and observed, at close range, the diseases his patients confronted him with.
One such disease was anthrax, which is spread from animals to humans throughcontaminated wool, by eating uncooked meat, or by breathing in airborne spores emanating from contaminated products. Koch examined under the microscope the blood of infected sheep and saw specific microorganisms that confirmed a thesis put forth ten years earlier by biologist C. J. Davaine (1812-1882) thatanthrax was caused by a bacillus. But Koch was not content to simply verify the work of another. He attempted to culture, or grow, these bacilli in cattleblood so he could observe their life cycle, including their formation into spores and their germination. Koch performed scrupulous research both in vitroand in animals before showing his work to Ferdinand Cohn, a botanistat the University of Breslau. Cohn was impressed with the work and replicatedthe findings in his own laboratory. He published Koch's paper in 1876.
In 1877, Koch published another paper that elucidated the techniques he had used to isolate Bacillus anthracis. He had dry-fixed bacterial cultures onto glass slides, then stained the cultures with dyes to better observe them, and photographed them through the microscope.
It was only a matter of time that Koch's research eclipsed his practice. In 1880, he accepted an appointment as a government advisor with the Imperial Department of Health in Berlin. His task was to develop methods of isolating andcultivating disease-producing bacteria and to formulate strategies for preventing their spread. In 1881 he published a report advocating the importance of pure cultures in isolating disease-causing organisms and describing in detail how to obtain them. The methods and theory espoused in this paper are still considered fundamental to the field of modern bacteriology. Four basic criteria, now known as Koch's postulates , are essential for an organism to be identified as pathogenic, or disease-causing. First, the organism must be foundin the tissues of animals with the disease and not in disease-free animals.Second, the organism must be isolated from the diseased animal and grown in apure culture outside the body, or in vitro. Third, the cultured organism must be able to be transferred to a healthy animal, who will subsequently show signs of infection. And fourth, the organisms must be able to be isolated fromthe infected animal.
While in Berlin, Koch became interested in tuberculosis, which he wasconvinced was infectious, and, therefore, caused by a bacterium. Several scientists had made similar claims but none had been verified. Many other scientists persisted in believing that tuberculosis was an inherited disease. In sixmonths, Koch succeeded in isolating a bacillus from tissues of humans and animals infected with tuberculosis. In 1882, he published a paper declaring that this bacillus met his four conditions--that is, it was isolated from diseased animals, it was grown in a pure culture, it was transferred to a healthy animal who then developed the disease, and it was isolated from the animal infected by the cultured organism. When he presented his findings before the Physiological Society in Berlin on March 24, he held the audience spellbound, sological and thorough was his delivery of this important finding. This day has come to be known as the day modern bacteriology was born.
In 1883, Koch's work on tuberculosis was interrupted by the Hygiene Exhibition in Berlin, which, as part of his duties with the health department, he helped organize. Later that year, he finally realized his dreams of travel when he was invited to head a delegation to Egypt where an outbreak of cholera had occurred. Louis Pasteur had hypothesized that cholera was caused by a microorganism; within three weeks, Koch had identified a comma-shapedorganism in the intestines of people who had died of cholera. However, when testing this organism against his four postulates, he found that the disease did not spread when injected into other animals. Undeterred, Koch proceeded toIndia where cholera was also a growing problem. There, he succeeded in finding the same organism in the intestines of the victims of cholera, and although he was still unable to induce the disease in experimental animals, he did identify the bacillus when he examined, under the microscope, water from the ponds used for drinking water. He remained convinced that this bacillus was the cause of cholera and that the key to prevention lay in improving hygiene and sanitation.
Koch returned to Germany and from 1885-1890 was administrator and professor at Berlin University. He was highly praised for his work, though some high-ranking scientists and doctors continued to disagree with his conclusions. But Koch was an adept researcher, able to support each claim with his exacting methodology. In 1890, however, Koch faltered from his usual perfectionism and announced at the International Medical Congress in Berlin that he had found aninoculum that could prevent tuberculosis. He called this agent tuberculin. People flocked to Berlin in hopes of a cure and Koch was persuaded to keep theexact formulation of tuberculin a secret, in order to discourage imitations.Although optimistic reports had come out of the clinical trials Koch had setup, it soon became clear from autopsies that tuberculin was causing severe inflammation in many patients. In January 1891, under pressure from other scientists, Koch finally published the nature of the substance, but it was an uncharacteristically vague and misleading report which came under immediate criticism from his peers.
Koch left Berlin for a time after this incident to recover from the professional setback. He also suffered from a personal scandal during this time, divorcing his wife in 1893 and immediately marrying an actress, Hedwig Freiberg, thirty years his junior. But the German government continued to support him throughout this time. An Institute for Infectious Diseases was established andKoch was named director. With a team of researchers, he continued his work with tuberculin, attempting to determine the ideal dose at which the agent could be the safest and most effective. The discovery that tuberculin was a valuable diagnostic tool (causing a reaction in those infected but none in those not infected), rather than a cure, helped restore Koch's reputation. In 1892 there was a cholera outbreak in Hamburg. Thousands of people died. Koch advocated strict sanitary conditions and isolation of those found to be infected with the bacillus. Germany's senior hygienist, Max von Pettenkofer, was unconvinced that the bacillus alone could cause cholera. He sneered at Koch's ideas,going so far as to drink a freshly isolated culture. Several of his colleagues joined him in this demonstration. Two developed symptoms of cholera, Pettenkofer suffered from diarrhea, but no one died; Pettenkofer felt vindicated in his opposition to Koch. Nevertheless, Koch focused much of his energy on testing the water supply of Hamburg and Berlin and perfecting techniques for filtering drinking water to prevent the spread of the bacillus.
In the following years, he gave the directorship of the Institute over to oneof his students so he could travel again. He went to India, New Guinea, Africa, and Italy, where he studied diseases such as the plague, malaria, rabies, and various unexplained fevers. In 1905, after returning to Berlin from Africa, he was awarded the Nobel Prize for physiologyand medicine for his work on tuberculosis. Subsequently, many other honors were awarded him recognizing not only his work on tuberculosis, but his more recent research on tropical diseases, including the Prussian Order Pour le Merits in 1906 and the Robert Koch medal in 1908. The Robert Koch Medal was established to honor the greatest living physicians, and the Robert Koch Foundation, established with generous grants from the German government and from theAmerican philanthropist, Andrew Carnegie (1835-1919), was founded to work toward the eradication of tuberculosis.
Meanwhile, Koch settled back into the Institute where he supervised clinicaltrials and production of new tuberculins. He attempted to answer, once and for all, the question of whether tuberculosis in cattle was the same disease asit was in humans. Between 1882 and 1901 he had changed his mind on this question, coming to believe that bovine tuberculosis was not a danger to humans,as he had previously thought. He espoused his beliefs at conferences in the United States and Britain during a time when many governments were attemptinglarge-scale efforts to minimize the transmission of tuberculosis through meatand milk.
Koch did not live to see this question answered. On April 9, 1910, three daysafter lecturing on tuberculosis at the Berlin Academy of Sciences, he suffered a heart attack from which he never fully recovered. He died at Baeden Baeden on May 27 at the age of 67. He was honored after death by the naming of the Institute after him.
Koch's obituaries are full of admiration for his perseverance and his scrupulous scientific process. Yet underneath the praise there is an acceptance thatthese same qualities--so useful to science--produced in the man a stubborn arrogance and an inability to give credit to the work of others or to admit his own mistakes. His early work with tuberculin and his defense that bovine tuberculosis was not harmful to humans are examples of his mistakes. Nevertheless, his strong will proved to be remarkably productive for science. He neverleft laboratory findings in the laboratory. Rather, he insisted, albeit stubbornly at times, that what he found in the laboratory should make a differencein the world. In the first paper he wrote on tuberculosis, he stated his lifelong goal, which he clearly achieved: "I have undertaken my investigations in the interests of public health and I hope the greatest benefits will accruetherefrom."