Fidec SAS

The study will compare the poliovirus type-2 pharyngeal mucosal excretion in the first week, and at 2 and 4 weeks following the administration of a challenge novel OPV2 (nOPV2) dose at 18 weeks of age in 2 parallel groups of infants

Study to determine immunogenicity and safety following administration of 2 doses of novel oral poliovirus vaccine type 2 (nOPV2) given at different intervals of 1 week or 2 weeks or the standard 4-week interval in infants

The study will assess and compare the immune response and safety following the co-administration of Novel Oral Polio Type 2 (nOPV2) and bivalent Oral Polio Vaccine (bOPV) in comparison with nOPV2 or bOPV in infants aged 2 months who have never received vaccination against poliomyelitis.