Since humankind's earliest days, the rise of civilization led to a huge increase in the number and types of diseases that afflict the human population. Early prevailing theories about the causes of and cures for disease included superstitious beliefs, the application of herbal remedies, and the well-meant but ultimately misguided humoral theory of disease - a concept that persisted into the 19th century. Presenting a comprehensive history of the development of the germ theory of disease, ""Germ Theory"" profiles the major scientists who helped the theory, including Leeuwenhoek, Jenner, Pasteur, Lister, Koch, Walter Reed, and others. The discussion ends with an exploration of antibiotics and the modern problem of disease-resistance due to overuse of these drugs.