Title: Koch's postulates
Content:  Koch's postulates are four criteria designed to establish a causative relationship between a microbe and a disease. The postulates were formulated by Robert Koch and Friedrich Loeffler in 1884, based on earlier concepts described by Jakob Henle, and refined and published by Koch in 1890. Koch applied the postulates to describe the etiology of cholera and tuberculosis, both of which are now ascribed to bacteria. The postulates have been controversially generalized to other diseases. More modern concepts in microbial pathogenesis cannot be examined using Koch's postulates, including viruses (which are obligate intracellular parasites) and asymptomatic carriers. They have largely been supplanted by other criteria such as the Bradford Hill criteria for infectious disease causality in modern public health, and Falkow's criteria for microbial pathogenesis.
Title: Microorganism
Content:  disease.  In 1876, Robert Koch (1843–1910) established that microorganisms can cause disease. He found that the blood of cattle that were infected with anthrax always had large numbers of Bacillus anthracis. Koch found that he could transmit anthrax from one animal to another by taking a small sample of blood from the infected animal and injecting it into a healthy one, and this caused the healthy animal to become sick. He also found that he could grow the bacteria in a nutrient broth, then inject it into a healthy animal, and cause illness. Based on these experiments, he devised criteria for establishing a causal link between a microorganism and a disease and these are now known as Koch's postulates. Although these postulates 
Title: Robert Koch
Content:  which are summarized in Koch's four postulates. Koch's discovery of the causative agent of anthrax led to the formation of a generic set of postulates which can be used in the determination of the cause of most infectious diseases. These postulates, which not only outlined a method for linking cause and effect of an infectious disease but also established the significance of laboratory culture of infectious agents, became the "gold standard" in infectious diseases. Although Koch worked out the principles, he did not formulate the postulates, which were introduced by his assistant Friedrich Loeffler. Loeffler, reporting his discovery of diphtheria bacillus in 1883, stated three postulates as 
Title: Robert Koch
Content:  to fulfill those three postulates whose fulfillment is absolutely necessary for the strict proof of the parasitic nature of any such disease: 1) In the given diseased patients, there must always be shown [to be present] organisms in typical disposition. 2) The organisms to which one would attribute — according to their behavior in the diseased parts — a relevance for the occurrence of these changes, must be isolated and cultured in pure form. 3) The disease must be able to be reproduced experimentally via pure cultures.) The fourth postulate was added by an American plant pathologist Erwin Frink Smith in 1905, and is stated as: 
Title: Germ theory of disease
Content: 1) The microorganism must be found in abundance in all organisms suffering from the disease, but should not be found in healthy organisms. ; 2) The microorganism must be isolated from a diseased organism and grown in pure culture. ; 3) The cultured microorganism should cause disease when introduced into a healthy organism. ; 4) The microorganism must be reisolated from the inoculated, diseased experimental host and identified as being identical to the original specific causative agent. Robert Koch is known for developing four basic criteria (known as Koch's postulates) for demonstrating, in a scientifically sound manner, that a disease is caused by 
Title: Bacteria
Content:  handwashing in his hospital in the 1840s predated the spread of the ideas about germs themselves and attributed diseases to "decomposing animal organic matter", Lister was active later. Robert Koch, a pioneer in medical microbiology, worked on cholera, anthrax and tuberculosis. In his research into tuberculosis Koch finally proved the germ theory, for which he received a Nobel Prize in 1905. In Koch's postulates, he set out criteria to test if an organism is the cause of a disease, and these postulates are still used today. Ferdinand Cohn is said to be a founder of bacteriology, studying bacteria from 1870. Cohn was the first to classify bacteria based on their morphology. Though it was known in the nineteenth century that bacteria are the cause 
Title: Germ theory of disease
Content:  particular organism. These postulates grew out of his seminal work with anthrax using purified cultures of the pathogen that had been isolated from diseased animals. Koch's postulates were developed in the 19th century as general guidelines to identify pathogens that could be isolated with the techniques of the day. Even in Koch's time, it was recognized that some infectious agents were clearly responsible for disease even though they did not fulfill all of the postulates. Attempts to rigidly apply Koch's postulates to the diagnosis of viral diseases in the late 19th century, at a time when viruses could not be seen or isolated 
Title: Robert Koch
Content:   From 424:  "Wenn nun die Diphtherie eine durch Mikroorganismen bedingte Krankheit ist, so müssen sich auch bei ihr jene drei Postulate erfüllen lassen, deren Erfüllung für den stricten Beweis der parasitäten Natur einer jeden derartigen Krankheit unumgänglich nothwendig ist:  1)  Es müssen constant in den local erkrankten Parteien Organismen in typischer Anordnung nachgewiesen werden. 2)  Die Organismen, welchen nach ihrem Verhalten zu den erkrankten Theilen eine Bedeutung für das Zustandekommen dieser Veränderungen beizulegen wäre, müssen isolirt und rein gezüchtet werden. 3)  Mit den Reinculturen muss die Krankheit experimentell wieder erzeugt werden können." (Now if diphtheria is a disease that's caused by microorganisms, then it must also be 
Title: Microbiology
Content:  solidifying microbiology's identity as a biological science. One of his students, Adrien Certes, is considered the founder of marine microbiology. Pasteur also designed methods for food preservation (pasteurization) and vaccines against several diseases such as anthrax, fowl cholera and rabies. Koch is best known for his contributions to the germ theory of disease, proving that specific diseases were caused by specific pathogenic microorganisms. He developed a series of criteria that have become known as the Koch's postulates. Koch was one of the first scientists to focus on the isolation of bacteria in pure culture resulting in his description of several 
Title: Koch's postulates
Content:  Koch's postulates have played an important role in microbiology, yet they have major limitations. For example, Koch was well aware in the case of cholera that the causal agent, Vibrio cholerae, could be found in both sick and healthy people, invalidating his first postulate. Furthermore, viral diseases were not yet discovered when Koch formulated his postulates, and there are many viruses that do not cause illness in all infected individuals, a requirement of the first postulate. Additionally, it was known through experimentation that Helicobacter pylori caused mild inflammation of the gastric lining when ingested. As evident as the inflammation was, it still did not immediately convince skeptics that H. pylori was 

Question: who developed a set of postulates to prove that specific microorganisms cause disease?
Answer: Robert Koch.
Friedrich Loeffler.