In today’s scientist spotlight post, we will learn about German physician and microbiologist Robert Koch. Born in Clausthal, Hanover, Germany, Koch was academically inclined from a young age. He went on to study the natural sciences in university, before switching over to medicine, where he earned his medical degree in 1866, graduating with high distinction from the University of Göttingen.

Koch’s research earned him the accolade of being called the father of bacteriology. During his time, the germ theory of disease, which states that microbes are what cause disease, was on the rise, due to work by other microbiologists such as Louis Pasteur. The issue, however, was not just determining whether a disease was caused by a microbe, but determining which specific microbe was responsible. This is important, because then treatments such as drugs could be developed through experiments on the microbe in question. This is where one of Koch’s most important contributions was made: the development of Koch’s postulates. If you’ve been taking Minute School’s microbiology course, you will know that Koch’s postulates are a sort of test, with four criteria, designed to determine whether a specific microbe causes a disease or not. This may sound simple, but at the time it was profound, because other theories about the cause of disease, such as the now obsolete miasma theory, were prevalent.

Using his postulates, Koch was able to determine the cause of important infections at the time. For example, Koch determined that the cause of anthrax was the bacterium Bacillus anthracis. He also determined that tuberculosis, which at the time was believed to be an inherited disease, was caused by Mycobacterium tuberculosis.

For his research on diseases caused by microbes, mainly tuberculosis, Koch was awarded the Nobel Prize in Physiology or Medicine in 1905.