A Hungarian doctor called Ignaz Semmelweis (1818–1865) worked in a maternity hospital in Vienna, Austria, in the 19th century.

He noted that more deaths caused by infection occurred on maternity wards where medical students were working.

The medical students conducted autopsies on women dying of infections. Dr Semmelweis believed that the students carried infectious material to the ward on their hands and clothing.

He introduced a hand washing policy and the mortality rate fell drastically from 13-18% to about 2%. Unfortunately, he was unable convince his fellow obstetricians, and he was forced to resign, and he later, sadly, committed suicide.

Another noteworthy figure was Joseph Lister (1827-1912). Dr Lister was a British surgeon who demonstrated that disinfection of hands reduced surgical site infections.