According to conventional wisdom, our genes and lifestyles are the most important causes of cancer, heart disease, and other killer ailments today. Conventional wisdom is wrong. In this bold, visionary book, biologist Paul W. Ewald argues that these serious illnesses are caused by a virtual plague of chronic infections. Acute infections give the sufferer symptoms almost immediately; the flu, cholera, even Ebola are all well-known and easy-to-identify examples of acute illnesses. Chronic infections, however, are stealthy predators that may not produce any symptoms for decades, and so remain almost undetectable, but eventually they ruin the sufferer's life. The netherworld of stealth infections is now opening before us. In Plague Time, Ewald puts forth an astonishing and profound argument that challenges our modern beliefs about disease: it is germs -- not genes -- that mold our lives and cause our deaths. Building on the recently recognized infectious origins of ulcers, miscarriages, and cancers, he draws together a startling collection of discoveries that now implicate infection in the most destructive chronic diseases of our time, such as heart disease, Alzheimer's, and schizophrenia. Acclaimed for years as one of the most important thinkers alive today on the genesis of disease, Ewald now explodes conventional medical thinking with a new comprehensive view of what germs do. Some people worry about dangerous germs "going global." In most cases it is already too late. The most dangerous germs among us have already been disseminated globally. Ewald explains how evolution in this worldwide environment makes some germs turn nasty while some become harmless. Most importantly, he shows how we can work together to master our modern infectious plagues by controlling disease evolution. He reveals that we live in an ecosystem of microbes, and we must understand them to avoid their deadly damage.