Poliovirus Vaccine Trial in Bangladesh

This randomized clinical trial will assess the immune response in infants following administration of three types of oral poliovirus vaccine trivalent OPV (tOPV), monovalent OPV type 1 (mOPV1), bivalent OPV types 1 and 3 (bOPV) using two different schedules: a short schedule with administration at two week intervals and the usual schedule at four week intervals. The results of this study will guide the Global Polio Eradication Program in the implementation of new strategies that may: 1) improve the quality of the response to outbreaks following importation of wild poliovirus type 1 by shortening the interval at which several OPV doses are provided; 2) prevent alternate outbreaks of type 1 and type 3 poliovirus by using bOPV in outbreak responses in countries with weak routine immunization systems; and 3) prevent the emergence of type 2 vaccine-derived poliovirus through the replacement of tOPV with bOPV in immunization campaigns and routine immunization programs.