The “International Day of Hand Hygiene” on May 5 was initiated by the World Health Organization in 2009. Since then the WHO campaign emphasizes hand disinfection as the most effective single measure to break the chain of infection. This may seem like common sense to many people today, yet it wasn’t until the mid-19th century that some doctors began to wash their hands before examining patients – and even then, only in certain cases.
The father of hand hygiene
Ignaz Semmelweis, a Hungarian doctor working in Vienna General Hospital between 1844 and 1848, is known as the father of hand hygiene. The hospital was one of the largest in the world for teaching, and its maternity wing was so big that it was divided into two wards: one for doctors and their students and one for midwives and their students.
In 1846, Semmelweis realized that the women giving birth in the medical student/doctor-run maternity ward were much more likely to develop “childbed fever” (now known as streptococcal infection), and die compared to the women giving birth in the adjacent midwife-run maternity ward. He decided to investigate, seeking differences between the two wards. In the end the death of his colleague Jakob Kolletschka in 1847 led him to a breakthrough.
Kolletschka had cut his finger on a scalpel during an autopsy, and developed an infection that killed him. Semmelweis theorized that his colleague died because “cadaveric matter” had entered his body through his wound, and wondered whether a similar type of infection could be happening in the doctors’ maternity ward. He had already noticed that doctors and medical students often examined the women directly after performing an autopsy. Midwives did not conduct surgery or autopsies, so they and the women on their ward were not exposed to these particles.
Semmelweis now imposed a new rule mandating that doctors wash their hands with chlorinated lime after autopsies. It was indeed a big improvement as between 1848 and 1859 the maternal mortality rate in the doctors’ ward dropped to around the same level as the midwives’ ward. This was the first proof that cleansing hands could prevent infection.
Unfortunately, the innovation was not very popular. Although he was able to prove his success epidemiologically, the causes of infections were still unknown. The idea that disinfecting hands in chlorinated lime would reduce the rate of infection simply did not fit in with the then current theory of miasmas and contagions. The result was hostility and exclusion. Only years later Louis Pasteur and Robert Koch laid the foundations for today’s microbiology.
Florence Nightingale’s rules still matter
A few years later, in the Crimean War (1853 to 1856), Florence Nightingale became another pioneer of handwashing. Her approach to caring for wounded soldiers and training nurses saved and improved countless lives. At a time when most people believed that infections were caused by foul odors called miasmas, Florence Nightingale implemented handwashing and other hygiene practices in the war hospital in which she worked. In her 1860 publication “Notes on Nursing” she wrote that “Every nurse ought to be careful to wash her hands very frequently during the day.”
Sadly, the hand hygiene practices promoted by Semmelweis and Nightingale were not widely adopted. Only when scientists like Pasteur and Koch started to realize that certain diseases and infections are caused by certain microorganisms, the importance of hand washing as a critical hygienic practice took hold in the medical world. For example, the British surgeon Joseph Lister drastically improved patient mortality by advocating that surgeons wash their hands and sterilize their instruments in between patients.
Today, medical and health professionals consider hand washing a critical hygienic practice, both for themselves and their patients. The fact that we now have a rich knowledge of hand hygiene and a range of hand disinfectants and test methods to prove their effectiveness and safety, is the result of the work of many researchers and developers. This knowledge forms the basis for finding solutions to current challenges like the outbreak of swine flu in 2009 and the current COVID-19 pandemic.
