Some countries in Africa report that approximately one-third of their adult populations are infected with HIV. Epstein wondered how such a state of affairs came about. Seeking answers, she contracted with a biotechnical company to go to Africa and work toward discovering an AIDS vaccine. What she subsequently learned exploded some preconceived and widely shared notions about AIDS, about how African culture all but ensures its spread, and about what might be a deceptively simple answer to the complex question of how to stem that spread. Her absorbing report reveals governmental inefficiencies and medical bureaucracies and social structures that have done nothing to slow the epidemic's pace—and may be accelerating it. Besides the epidemic's social and medical aspects, she discusses the business of AIDS, and she examines the mystery of how the HIV infection rate dropped some 70 percent between 1992 and 1997 in Uganda and the Kagera region of Tanzania; she believes that the invisible cure involved in that plunge provides clues to resolving the issue of AIDS in Africa generally