Robert Koch: History, Accomplishments & Contribution to Microbiology

There have been many brilliant scientists to come out of Germany throughout the years, but Robert Heinrich Herman Koch stands out as one of the country’s all-time greats.

Koch established the field of bacteriology as we know it today and contributed to our understanding of the origins, spread, and treatment of a wide range of bacterial illnesses. The German scientist, who is often hailed as the “Father of Bacteriology”, received the Nobel Prize in Physiology or Medicine in 1905 for his research on tuberculosis.

Formative Years

Born in 1843, the German physician and microbiologist was raised by Hermann Koch and Mathilde Julie Henriette.

Koch taught himself how to read and write before beginning elementary school in 1848. After finishing his secondary education in 1862, he went on to enroll at the University of Göttingen to study natural science.

The budding scientist explored the fields of mathematics, botany and physics but ultimately chose to read medicine since that was his primary passion. However, everything changed as he joined a team headed by Jacob Henle, a German anatomist who was known for his groundbreaking theory regarding contagion in 1840. With the aid of Henle, Koch conducted research work on uterine nerve structure. His research caught the attention of renowned German physician Rudolf Ludwig Virchow.

While in medical school, he had the opportunity to do a number of research works at the Physiological Institute. Some of those works covered the secretion of succinic acid.

He graduated from medical school in 1866 and had a total career overhaul after he was given a microscope for his birthday. This later cemented his career in microbiology.

Did you know?

When the Franco-Prussian War broke out in 1870, Koch enlisted and went on to serve as a volunteer surgeon in the German army for about a year. After leaving the army, he went on to work as a physician in Wolsztyn (formerly Posen) in Poland.

Robert Koch’s Accomplishments

The German physician stayed true to his research in microbiology and continued his findings regarding microorganisms that were in connection to the symptoms of his patients. He struck gold during his early years of research as he managed to develop a technique to grow and culture bacteria in his lab.

This ground-breaking discovery led to other major accomplishments, including showing the scientific community to how to isolate and grow pathogens of his choice in a pure laboratory culture. This led to the discovery of anthrax bacillus. The findings were later published in 1876 with the help of fellow German biologist, Ferdinand Julius Cohn.

Other notable achievements

Unbeknownst to many, Koch was the first researcher to employ the use of an oil immersion lens and a condenser that enabled smaller objects to be seen. He was also the first scientist to use photography as a means of microscopic observations. Listed below are other scientific contributions of the German physician.

Director of the Royal Prussian Institute for Infectious Diseases

The physician later gained enough recognition to be appointed as an administrator and professor at Berlin University in 1885 while taking on the role of Director of Hygienic Institute and Chair (Professor of hygiene) of the Faculty of Medicine.

The opportunity to become a director of the Royal Prussian Institute for Infectious Diseases was too great to pass. Therefore, he resigned his role as a professor in Berlin in order to take on this new role in 1891.

This new role came with some severe disadvantages as the Prussian Ministry of Health insisted that any new inventions of Koch’s would be regarded as the property of the government. Therefore, Koch was not entitled to receive any compensation for his works. This meant that it was impossible for Koch to apply for any patent protection for his inventions under the Prussian government.

Solved the problem of bacteria cultivation

Scientists before Koch found it immensely difficult to culture bacteria in an environment which would be conducive enough for it to grow. As a result, it was difficult for the bacteria to be studied without destroying its potency.

Koch published his work titled “Zur Untersuchung von Pathogenen Organismen” (Methods for the Study of Pathogenic Organisms) in 1881, demonstrating a new and improved method of growing bacteria. He did this by making the culture medium solid using liquid agar and gelatin.

He then placed the medium on what he called a moist chamber (feuchte Kammer) to create a conducive environment for the culture. This new plating method, which French scientist Louis Pasteur described as an amazing development, brought about the discovery of new bacteria such as glanders (Burkholderia mallei) in 1882 and diphtheria (Corynebacterium diphtheriae) in 1884.

Fellow German bacteriologist Georg Theodor August Gaffky used Koch’s moist chamber to discover the bacterium of typhoid (Salmonella enterica) in 1884.

Robert Koch influenced the creation of Petri dish

It wasn’t until 1887 when Koch’s assistant, Julius Richard Petri, developed a slightly more effective method of bacteria culture through the invention of the Petri dish.

Petri’s only modification was that he got rid of the glass plates and used the circular glass dish directly. Other than the fact that Petri’s dish reduced the cases of contamination of culture mediums, the technology was the same. In all fairness, one would not be wrong to call what we all know today as Petri dish “Koch dish”.

Discovered the rod-shaped bacterium that causes Anthrax

Koch believed that the idea of spontaneous generation as proposed by the Greek philosopher Aristotle did not stand after he linked the spread of a specific microorganism to a specific disease. This new theory states that microorganisms known as pathogens or “germs” can lead to disease, and Koch had proved it to be right.

Koch’s research on anthrax was very crucial as he later discovered its causative agent to be Bacillus anthracis, a rod-shaped bacterium. His publication of the disease in 1877 marked the first time a bacterium had ever been photographed, making the discovery of the anthrax bacterium (Bacillus anthracis) in 1876 the foundation of modern bacteriology.

A leading proponent of the germ theory of disease

Koch’s work went a long way in further disproving the doctrine of spontaneous generation and the misasma theory. The former states that living things could emerge from nonliving things. Koch, like French microbiologist Louis Pasteur, thus became one of the leading proponents of the germ theory. The theory states that diseases are in fact caused by microorganisms called pathogens or germs.

The discovery of Cholera

The great cholera epidemic in Egypt in 1883 caught the interest of the German physician and prompted him to investigate. Koch later realized that the mucus that was secreted by patients who died of cholera were indeed infected. However, even though he had his suspicions, he couldn’t identify the causative pathogen.

After performing several autopsies, he realized that the causative agent was a bacterial infection. His investigation led him to some contaminated water reservoirs. He began his research on it in a pure culture medium on 7 January 1884. He later came to the conclusion that a poison was used by the bacterium to infect the inhabitants.

Prior to Koch, similar discoveries had been made by Italian physician Filippo Pacini in 1854 and Catalan physician Joaquim Balcells i Pascual. Unlike Koch’s, those works failed to identify the bacterium as the cause of cholera.

Koch’s works helped fellow German bacteriologist Richard Friedrich Johannes Pfeiffer in his work. Pfeiffer was able to advance the work and thereafter called the comma bacillus Vibrio cholera in 1896.

It wasn’t until 1959 that the Indian scientist Sambhu Nath De discovered this poison and called it the cholera toxin.

His work on acquired immunity

Koch delved deep into the phenomenon of acquired immunity in 1900 during his research in German New Guinea. He observed that the Papuan people had concentrated amounts of plasmodium parasite in their blood yet showed little or no signs of the disease i.e., malaria.

However, outsiders such as himself who just arrived in the country often fell sick immediately. He concluded with the theory of acquired immunity, stating that the longer you stay in an environment of the pathogen, the more resistant you are against said pathogen.

Koch’s work on Tuberculosis

Before Koch would take on the deadly disease called tuberculosis, scientists all over the world believed that the disease was inherited. This notion spiked the interest of the German physician as he set out to find the truth surrounding the killer disease.

He began his research in the 1880’s, culturing the disease and staining it with potassium hydroxide for 24 hours. The culture presented a rod-like structure to prove that the causative agent of tuberculosis was a slow-growing Mycobacterium tuberculosis. Koch published the discovery in 1882 as “Die Ätiologie der Tuberkulose” (The Etiology of Tuberculosis). It is worth noting that the bacterium of tuberculosis was first discovered by Filippo Pacini in 1854.

Koch went a step further to use the extract from tuberculosis in an attempt to find a cure for the disease. He began clinical trials with the extract known as “tuberkulin” in 1891. Unfortunately, all 1061 patients who were administered the supposed cure during the clinical trials lost their lives.

This dealt a great blow to Koch’s career and reputation and was widely regarded as Koch’s “greatest failure.” His attempt would later prove beneficial as his extract was later used for hypersensitivity tests for tuberculosis patients.

He formulated Koch’s Postulate

The Koch’s postulate was formulated during the German physician’s research on anthrax. He then went on to provide the necessary steps on how to isolate the disease-causing organisms and culture them safely without contamination. These steps were formulated in 1883 by his assistant Friedrich Loeffler to help other scientists not only link cause and effect of an infectious disease but also establish the significance of laboratory culture of infectious agents.

Other Interesting Facts about Heinrich Hermann Robert Koch

The German physician married Emma Adolfine Josephine Fraatz in 1867. The marriage, which produced two children, ended in divorce in 1893. A few months after the divorce, he tied the knot with an actress called Hedwig Freiberg. Here are some other facts.

•  Koch was awarded the Knight Grand Cross in the Prussian Order of the Red Eagle in 1890
• He was also honored with the Order of the Crown by Emperor Wilhelm I.
• Every year on March 24th, in honor of the day that Koch identified the tuberculosis bacteria, the World Health Organization (WHO) officially observes “World Tuberculosis Day.”
• On the frieze of the Bloomsbury location of the London School of Hygiene & Tropical Medicine, Koch’s name appears among those of 23 other notable figures from the fields of hygiene and tropical medicine.
• The 1940 film “Dr. Ehrlich’s Magic Bullet” depicted Koch and his friendship with Paul Ehrlich, who created a technique to diagnose tuberculosis.
• Koch’s biggest rival Louis Pasteur had major disputes over the discovery of anthrax bacillus in 1876 as the causality agent. Pasteur was convinced that Koch’s discovery was not the full proof of causality, but his anthrax vaccine developed in 1881 was.
• Autopsy reports showed that Koch died from complications after suffering from heart attack in 1910.