We all know that washing your hands it's one of the best ways to prevent germs from spreading. But until relatively recently hand washing was something relegated primarily to religious rituals and cultural ceremonies. And the first person to suggest that doctors wash their hands before surgery was put in a mental hospital! Why? Watch the episode to find out.

Originally released by Knowledgemotion, 2018. Streaming video file encoded with permission for digital streaming by Infobase on February 21, 2020.