Starting this fine book I knew very little about the history of the germ theory of infectious disease. It’s purpose is to give an idea of how difficult it was for the germ theory to become dominant and the actors who promoted it to win over scientific medicine. Most of the action takes place in the later 19th century and early 20th century. Before hand no one knew what caused disease but Doctors certainly had their ideas. Almost none of them were correct or had any effect on the disease itself though they might give symptomatic relief but usually not. Lister, Pasteur and Koch provided the experiments and experience to show that germ theory wasn’t just a theory. The author discusses vaccines and antibiotics in this chronological narrative that is well written and informative. The narrator has a great voice for nonfiction and made the listening experience even more rewarding.