These recommendations represent the first statement by the Advisory Committee on Immunization Practices (ACIP) on the use of an oral, live rotavirus vaccine licensed by the Food and Drug Administration on August 31, 1998, for use among infants. This report reviews the epidemiology of rotavirus, describes the licensed rotavirus vaccine, and makes recommendations regarding its use for the routine immunization of infants in the United States. These recommendations are based on estimates of the disease burden of rotavirus gastroenteritis among children in the United States and on the results of clinical trials of the vaccine. Rotavirus affects virtually all children during the first 5 years of life in both developed and developing countries, and rotavirus infection is the most common cause of severe gastroenteritis in the United States and worldwide. In the United States, rotavirus is a common cause of hospitalizations, emergency room visits, and outpatient clinic visits, and it is responsible for considerable health-care costs. Because of this large burden of disease, several rotavirus vaccines have been developed. One of these vaccines - an oral, live, tetravalent, rhesus-based rotavirus vaccine (RRV-TV) -- was found to be safe and efficacious in clinical trials among children in North America, South America, and Europe and on the basis of these studies is now licensed for use among infants in the United States. The vaccine is an oral, live preparation that should be administered to infants between the ages of 6 weeks and 1 year. The recommended schedule is a three-dose series, with doses to be administered at ages 2, 4, and 6 months. The first dose may be administered from the ages of 6 weeks to 6 months; subsequent doses should be administered with a minimum interval of 3 weeks between any two doses. The first dose should not be administered to children aged > or =7 months because of an increased rate of febrile reactions after the first dose among older infants. Second and third doses should be administered before the first birthday. Implementation of these recommendations in the United States should prevent most physician visits for rotavirus gastroenteritis and at least two-thirds of hospitalizations and deaths related to rotavirus.