Robert Koch
Heinrich Hermann Robert Koch (English: /kɒx/ KOKH,[1][2] German: [ˈʁoːbɛʁt ˈkɔx] ⓘ; 11 December 1843 – 27 May 1910) was a German physician and microbiologist. As the discoverer of the specific causative agents of deadly infectious diseases including tuberculosis, cholera and anthrax, he is regarded as one of the main founders of modern bacteriology. As such he is popularly nicknamed the father of microbiology (with Louis Pasteur[3]), and as the father of medical bacteriology.[4][5] His discovery of the anthrax bacterium (Bacillus anthracis) in 1876 is considered as the birth of modern bacteriology.[6] Koch used his discoveries to establish that germs "could cause a specific disease"[7] and directly provided proofs for the germ theory of diseases, therefore creating the scientific basis of public health,[8] saving millions of lives.[9] For his life's work Koch is seen as one of the founders of modern medicine.[10][11]
For other people named Robert Koch, see Robert Koch (disambiguation).
Robert Koch
27 May 1910 (aged 66)
- ForMemRS (1897)
- Nobel Prize in Medicine (1905)
- Pour le Mérite (1906)
Imperial Health Office, Berlin
University of Berlin
While working as a private physician, Koch developed many innovative techniques in microbiology. He was the first to use the oil immersion lens, condenser, and microphotography in microscopy. His invention of the bacterial culture method using agar and glass plates (later developed as the Petri dish by his assistant Julius Richard Petri) made him the first to grow bacteria in the laboratory. In appreciation of his work, he was appointed to government advisor at the Imperial Health Office in 1880, promoted to a senior executive position (Geheimer Regierungsrat) in 1882, Director of Hygienic Institute and Chair (Professor of hygiene) of the Faculty of Medicine at Berlin University in 1885, and the Royal Prussian Institute for Infectious Diseases (later renamed Robert Koch Institute after his death) in 1891.
The methods Koch used in bacteriology led to establishment of a medical concept known as Koch's postulates, four generalized medical principles to ascertain the relationship of pathogens with specific diseases. The concept is still in use in most situations and influences subsequent epidemiological principles such as the Bradford Hill criteria.[12] A major controversy followed when Koch discovered tuberculin as a medication for tuberculosis which was proven to be ineffective, but developed for diagnosis of tuberculosis after his death. For his research on tuberculosis, he received the Nobel Prize in Physiology or Medicine in 1905.[13] The day he announced the discovery of the tuberculosis bacterium, 24 March 1882, has been observed by the World Health Organization as "World Tuberculosis Day" every year since 1982.
Career[edit]
After graduation in 1866, Koch briefly worked as an assistant in the General Hospital of Hamburg. In October that year he moved to Idiot's Hospital of Langenhagen, near Hanover, as a general physician. In 1868, he moved to Neimegk and then to Rakwitz in 1869. As the Franco-Prussian War started in 1870, he enlisted in the German army as a volunteer surgeon in 1871 to support the war effort.[19] He was discharged a year later and was appointed as a district physician (Kreisphysikus) in Wollstein in Prussian Posen (now Wolsztyn, Poland). As his family settled there, his wife gave him a microscope as a birthday gift. With the microscope, he set up a private laboratory and started his career in microbiology.[20][21]
Koch began conducting research on microorganisms in a laboratory connected to his patient examination room.[18] His early research in this laboratory yielded one of his major contributions to the field of microbiology, as he developed the technique of growing bacteria.[26] Furthermore, he managed to isolate and grow selected pathogens in a pure laboratory culture.[26] His discovery of the anthrax bacillus (later named Bacillus anthracis) hugely impressed Ferdinand Julius Cohn, professor at the University of Breslau (now the University of Wrocław), who helped him publish the discovery in 1876.[19] Cohn had established the Institute of Plant Physiology[27] and invited Koch to demonstrate his new bacterium there in 1877.[28] Koch was transferred to Breslau as district physician in 1879. A year after, he left for Berlin when he was appointed a government advisor at the Imperial Health Office, where he worked from 1880 to 1885.[29] Following his discovery of the tuberculosis bacterium, he was promoted to Geheimer Regierungsrat, a senior executive position, in June 1882.[30]
In 1885, Koch received two appointments as an administrator and professor at Berlin University. He became Director of Hygienic Institute and Chair (Professor of hygiene) of the Faculty of Medicine.[19] In 1891, he relinquished his professorship and became a director of the Royal Prussian Institute for Infectious Diseases (now the Robert Koch Institute) which consisted of a clinical division and beds for the division of clinical research. For this he accepted harsh conditions. The Prussian Ministry of Health insisted after the 1890 scandal with tuberculin, which Koch had discovered and intended as a remedy for tuberculosis, that any of Koch's inventions would unconditionally belong to the government and he would not be compensated. Koch lost the right to apply for patent protection.[31] In 1906, he moved to East Africa to research a cure for trypanosomiasis (sleeping sickness). He established the Bugula research camp where up to 1000 people a day were treated with the experimental drug Atoxyl.[32]
Scientific contributions[edit]
Techniques in bacteria study[edit]
Robert Koch made two important developments in microscopy; he was the first to use an oil immersion lens and a condenser that enabled smaller objects to be seen.[15] In addition, he was also the first to effectively use photography (microphotography) for microscopic observation. He introduced the "bedrock methods" of bacterial staining using methylene blue and Bismarck (Vesuvin) brown dye.[8] In an attempt to grow bacteria, Koch began to use solid nutrients such as potato slices.[26] Through these initial experiments, Koch observed individual colonies of identical, pure cells.[26] He found that potato slices were not suitable media for all organisms, and later began to use nutrient solutions with gelatin.[26] However, he soon realized that gelatin, like potato slices, was not the optimal medium for bacterial growth, as it did not remain solid at 37 °C, the ideal temperature for growth of most human pathogens.[26] And also many bacteria can hydrolyze gelatin making it a liquid. As suggested to him by his post-doctoral assistant Walther Hesse, who got the idea from his wife Fanny Hesse, in 1881, Koch started using agar to grow and isolate pure cultures.[33] Agar is a polysaccharide that remains solid at 37 °C, is not degraded by most bacteria, and results in a stable transparent medium.[26][34]
Personal life[edit]
In July 1867, Koch married Emma (Emmy) Adolfine Josephine Fraatz, and the two had a daughter, Gertrude, in 1868.[13] Their marriage ended after 26 years in 1893, and later that same year, he married actress Hedwig Freiberg (1872–1945).[13]
On 9 April 1910, Koch suffered a heart attack and never made a complete recovery.[25] On 27 May, three days after giving a lecture on his tuberculosis research at the Prussian Academy of Sciences, Koch died in Baden-Baden at the age of 66.[18] Following his death, the Institute named its establishment after him in his honour. He was irreligious.[70]
