Rotavirus is a major cause of death and complications in infants, especially in sub-Saharan Africa. In this randomized clinical trial in Niger, a low-cost, heat-stable rotavirus vaccine was shown to have nearly 70% efficacy against severe rotavirus gastroenteritis. Rotavirus is a leading cause of severe gastroenteritis among young children and is responsible for approximately 37% of deaths from diarrhea among children younger than 5 years of age worldwide. 1 , 2 Two live, oral, attenuated rotavirus vaccines (Rotarix, GlaxoSmithKline, and RotaTeq, Merck) have met the prequalification requirements of the World Health Organization (WHO), stipulations that allow for purchase by United Nations agencies. 3 The efficacy of these vaccines has been shown, with an important effect on hospital admissions and mortality. 4 – 14 Sub-Saharan Africa has the highest rate of death associated with rotavirus disease, 1 but vaccination on a large scale presents challenges. . . .