An inspiring story of doctors who changed the health care of an African nationBy 2006, Dilan Ellegala, an accomplished neurosurgeon, had reached the highest rungs of the American medical establishment. But he was on the verge of burning out. In search of personal restoration, he took a sabbatical at a remote missionary hospital in Haydom, Tanzania. While there, he discovered a medical world entirely different from the one he knew: Tanzania had just three neurosurgeons in a country with a population of 43 million.During his stay, he met Emmanuel Mayegga, an assistant medical officer. Though Mayegga had no medical degree, Ellegala realized that Mayegga had the dexterity, intelligence, and confidence to be a great surgeon. Dr. Ellegala began training Mayegga to perform brain-surgery procedures, giving him the tools to become an agent of change in his own country. In his turn, Mayegga trained another young health-care worker, Emanuel Nuwas, to save lives with...