(December 11, 1843 – May 27, 1910)
Koch is one of the scientists whose works supplanted Galen’s age-long Miasma Theory: by consolidating the more modern and more accurate Germ Theory of Diseases. He developed what became known as the Koch’s Postulates in the 19th century. In it he demonstrated the exponential abundance of pathogenic microbes in individuals afflicted with infectious diseases. He also proved that these microbes could be isolated from their hosts, and grown into pure laboratory cultures capable of instigating the same illnesses if (or when) inoculated into healthy persons. Finally, he showed that subsequent isolates from these new patients were identical to the pathogens from the initial hosts. Robert Koch discovered and isolated Bacillus anthracis. He was also the first person to identify and analyze Mycobacterium tuberculosis. Although Vibrio cholerae was first isolated by Filippo Pacini, it was Koch’s rediscovery (three decades later) which brought attention to it. After these bacteriological works, he briefly paid attention to protozoa: studying Plasmodium falciparum and Entamoeba histolytica. He remained a lifelong researcher; and his researches helped pave the way for modern lab techniques: thanks to the early encouragements from Jakob Henle (the anatomy professor who whetted his appetite for evidence-based-medicine). Koch would in turn inspire an up-and-coming Paul Ehrlich. His groundbreaking works advanced laboratory analysis, improved public health, and instigated further researches on infectious diseases.