A sprawling, engrossing, even terrifying study of how humankind can expect to suffer continuous lethal eruptions of illness, despite the progress of medicine. The fundamental idea has caught on broadly, but Garrett, a gifted popular science writer, is enlightening on many of the subthemes and details, from Ebola and Marburg virus to HIV, hanta viruses, and seal plague. The increasing ease of international travel and the creation of megacities conducive to the spread of disease are two matters of particular importance to those concerned with international relations. Indeed, as reflection on medical history suggests, the spread and course of pandemics may affect international relations in powerful ways. A shorter book might have been made of this text, and the writing has a distinctly panicky edge, but on balance, after reading this work one begins to think a note of hysteria may be justified.