Every time we sneeze, there seems to be a new form of flu: bird flu, swine flu, Spanish flu, Hong Kong flu, H5N1, and most recently, H5N7. Through human stories and advanced science, the author explores the origins of seven diseases: Mad Cow Disease, HIV/AIDS, Salmonella DT104, Lyme Disease, Hantavirus, West Nile, and new strains of flu.