An excellent read, relevant to your post, is Bellevue Three Centuries of Medicine and Mayhem at America's Most Storied Hospital, by David Oshinsky. Besides describing horrendous, disease-propagating conditions at hospitals in the 19th century, the book highlights the recalcitrance of the medical community to change. Harvesting corpses from graves for anatomy study, performing autopsies and then going directly to the maternity ward, without hand-washing--mind-boggling details remind us to be skeptical of orthodoxy, in any context.