Born Dec. 11, 1843, in Klausthal, died May 27, 1910, in Baden-Baden. German microbiologist; one of the founders of modern bacteriology and epidemiology.

Koch graduated from the University of Gottingen in 1866. He worked between 1872 and 1880 as a public health physician in Wollstein (present-day Wolsztyn, People’s Republic of Poland), where he organized a home laboratory and performed his first microbiological studies. He was a professor at the University of Berlin and director of the Institute of Hygiene from 1885 to 1891. He was the director of the Institute for Infectious Diseases in Berlin from 1891 to 1904, and the institute was later named after him.

Koch’s principal studies were devoted to the discovery of microorganisms as the cause of infectious diseases and to methods of combating these microorganisms. For this purpose, Koch undertook expeditions to Egypt, India, New Guinea, and Java. He was the first to isolate a pure culture of the anthrax bacillus, which he had discovered previously. By means of the culture he demonstrated the ability of the bacillus to form spores and explained the pathways for the spread of anthrax. He discovered the tuberculosis bacillus in 1882. Koch formulated the criteria for determining the link between a disease and a given microorganism (Koch’s postulates), which led to the identification of the microbe responsible for Asiatic cholera in 1883. Koch produced the bacterial preparation tuberculin in 1890 and used it for the treatment of tuberculosis. However, the preparation turned out to be ineffective; it was later used only for diagnostic purposes. In this connection, he described the tuberculin reaction known as Koch’s phenomenon.

Koch developed the general methods of bacteriological re-search and proposed methods of disinfection. He was awarded the Nobel Prize in 1905.