There was an Hungarian/Austrian doctor who realised that he had less deaths of women giving birth when doctors washed their hands before treating them (after working in the morgue). He tried to convince the doctors to wash their hands (though he didn’t quite understand what they were carrying over from the morgue). He made quite a few enemies because doctors didn’t like to think they were responsible for the deaths. Here’s a link that tells his story: https://www.npr.org/sections/health-shots/2015/01/12/375663920/the-doctor-who-championed-hand-washing-and-saved-women-s-lives
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