Hand washing in hospitals emerged rather late in human history – around the 1840s according to the History Channel. This was based on some rather gruesome evidence.
Doctors began to notice that mothers’ deaths during childbirth were far higher in the doctors’ wards (about 98.4 deaths per 1000 births) compared to midwives’ wards (36.2 per 1000 births). One Hungarian doctor, Ignaz Semmelweis, started conducting some tests to see why women were dying at such high rates in doctors’ wards. At first, he thought the priests’ bells were scaring women as priests would walk through doctors’ wards only. But rerouting the priests did nothing. Then, he noticed that the doctors did a range of tasks during their day the midwives didn’t – including handling cadavers. He hypothesized that the doctors might be bringing matter from the cadavers into the wards on their hands. So, he made them wash their hands. The result was fantastic – deaths during childbirth plummeted in the doctors’ wards. Interestingly, it took Semmelweis a long time to convince other European doctors to follow his evidence-based practice, but eventually, his arguments won everyone over.