West Nile Virus, Mad Cow Disease, HIV/AIDS, Hantavirus, Lyme Disease and a new strain of Salmonella have all emerged during the 20th century as mysterious, yet significant risks to human health. These "plagues" are forcing us to modify our lifestyles in ways that minimize our chances of becoming a statistic in the latest tally of the afflicted. This book connects these emerging health risks and their ecological origins and weaves together a compelling argument: that changes humans have made to the environment, from warming the climate to clearing the forests, have contributed to, if not caused, a rising tide of diseases that are afflicting humans and many other species.