Emerging infectious diseases are often due to environmental disruption, which exposes microbes to a different niche that selects for new virulence traits and facilitates transmission between animals and humans. Thus, health of humans also depends upon health of animals and the environment - a concept called One Health. This book presents core concepts, compelling evidence, successful applications, and remaining challenges of One Health approaches to thwarting the threat of emerging infectious disease. Written by scientists working in the field, this book will provide a series of "stories" about how disruption of the environment and transmission from animal hosts is responsible for emerging human and animal diseases. * Explains the concept of One Health and the history of the One Health paradigm shift . * Traces the emergence of devastating new diseases in both animals and humans. * Presents case histories of notable, new zoonoses, including West Nile virus, hantavirus, Lyme disease, SARS, and salmonella. * Links several epidemic zoonoses with the environmental factors that promote them.