Research for infection protection

The 120th anniversary of the death of the "father of modern hygiene"
Max von Pettenkofer: Pursuing the right objective with the wrong assumption

Born on 3 December 1818 as the fifth of eight children, Max von Pettenkofer spent the first years of his life in poverty. Under the care of his godfather, he obtained an excellent scientific education and soon became part of the scientific elite. Despite a fundamental misunderstanding of the spread of disease, he revolutionised the hygiene situation in Munich and freed the city from the cholera epidemic [1, 2]. The Institute for Hygiene in Munich, which he led at the time, now bears his name in honour of his achievements. The 120th anniversary of his death falls on 10 February 2021.


Pathogenic vapours from soil

When von Pettenkofer began researching cholera in the middle of the 19th century, experts were divided into two camps. While one camp assumed that the disease was transmitted by people, as a proponent of miasma theory, von Pettenkofer believed there was a connection with vapours from soil. Although he suspected that a type of "germ" existed in humans, he was convinced that infectiousness only arose as a result of contact with contaminated soil and its vapours [1].
Even though this assumption was incorrect, it prompted him to do the right thing. He implemented extensive sanitary reforms in Munich, which at that time was immersed in filth and sewage. These included the provision of hygienic drinking water and the expansion of the sewage system, which drastically reduced the mortality rate of both cholera and typhus [1, 2].


Paving the way for modern environmental medicine

But von Pettenkofer's research was not limited to cholera – it included all environmental factors that have a significant impact on people and their health: air, water, soil, sewage, river pollution, heating, clothing and the urban environment [1, 2]. One of the factors that he studied in the course of his investigations was the quality of ambient air, and he defined what is now known as the Pettenkofer number – a maximum CO2 value of 1000 ppm, which until recently was used to ensure a healthy indoor environment [3].


Rivalry between scientists

After von Pettenkofer had been held in high esteem for decades as a result of his pioneering work in the field of hygiene, his rival, Robert Koch, discovered the cholera bacterium Vibrio comma (now Vibrio cholerae) in 1883, thereby disproving miasma theory. In an attempt to prove that Koch was lying and restore his own reputation, von Pettenkofer took the extreme measure of drinking a solution containing Vibrio cholerae, after which he suffered from diarrhoea but did not die. But by that point, it was too late to reverse the downturn in his career. Von Pettenkofer was increasingly sidelined and took his own life at the age of 82 [4].

1. Locher WG. Max von Pettenkofer (1818–1901) as a Pioneer of Modern Hygiene and Preventive Medicine. Environmental Health and Preventive Medicine 2007;12: 238–245.
2. Evans AS. Pettenkofer Revisited. The Life and Contributions of Max von Pettenkofer (1818-1901). Yale Journal of Biology and Medicine 1973;46: 161–176.
3. "Mehr Infos/Luftqualität und CO2-Konzentration" [More info/Air quality and CO2 concentration] tab
4. Morabia A. Epidemiologic Interactions, Complexity, and the Lonesome Death of Max von Pettenkofer. American Journal of Epidemiology 2007;166: 1233–1238.