The goal of this project is to further develop Iocide, a novel iodine-based antimicrobial technology, for use as a topical bacteriocide for group B streptococci (GBS) in the vaginal tract of pregnant women during the intrapartum period. GBS is the leading cause of neonatal bacterial disease and death, and most frequently occurs in neonates as sepsis, meningitis, and pneumonia. Despite clinical advances to date, GBS continues to be a major cause of illness and death among newborns. Due to the limitations of current clinical strategies, a need exists for alternate approaches to prevent GBS-related neonatal disease. The following specific aims have been designed to achieve this goal: 1) to optimize the formulation of the Iocide vaginal gel, 2) to determine the effective range of Iocide in vitro, 3) to demonstrate safety and efficacy to the Iocide in animals, and 4) to determine safety and efficacy of Iocide in human clinical trials.