Pendergrast, a Vermont freelance, has written the history of the CDC's Epidemic Intelligence Service (EIS), a two-year program for idealistic young doctors, nurses, statisticians, sociologists, Ph.D.s in public health, anthropologists, and lawyers. During postings they can face Ebola in Africa, bird flu in Asia, clusters of salmonella food poisoning in America, or a seemingly endless array of other threats to health. The author celebrates EIS's successes but does not gloss over the moral shortcomings of the early years — such as vaccines tested on prisoners or institutionalized children — nor does he ignore bureaucratic in-fighting and politics.