Evaluation of the Immunogenicity and Safety of Concomitant Administration of Novel Oral Polio Type 2 Vaccine and Bivalent Oral Polio Vaccine

Inclusion Criteria:

1. Infants aged 8 weeks (-1, + 2 weeks) with birth weight >2,500 gm.
2. Healthy infants without obvious medical conditions like immunodeficiency diseases, severe congenital malformations, severe neurological diseases or any other disease that require high doses of corticosteroids or immunotherapies that preclude the subject to be in the study as established by the medical history and physical examination.
3. Written informed consent obtained from 1 or 2 parent(s) or legal guardian(s) as per country regulations.

Exclusion Criteria:

1. Infants who have received previous vaccination according to the National Immunization Program (NIP) (i.e. vaccination against poliomyelitis and/or receipt of diphtheria-tetanus-whole cell pertussis-hepatitis B-Haemophilus influenzae type b [DTPw-HB-Hib vaccine]).
2. Infants with anyone under 10 years of age in their household (living in the same house or apartment unit) who does not have complete "age appropriate" vaccination status with respect to poliovirus vaccines at the time of study vaccine administration according to the Dominican Republic NIP.
3. Infants having a member of their household (living in the same house or apartment unit) who is under 6 months of age at the moment of study vaccine administration.
4. Infants having a member of their household (living in the same house or apartment unit) who has received oral polio vaccine (OPV) in the previous 3 months before study vaccine administration.
5. Any confirmed or suspected immunosuppressive or known immunodeficient condition including human immunodeficiency virus infection in the potential participant or any member of the subject's household.
6. Family history of congenital or hereditary immunodeficiency.
7. Major congenital defects or serious uncontrolled chronic illness (neurologic, pulmonary, gastrointestinal, hepatic, renal, or endocrine).
8. Known allergy to any component of the study vaccines or to any antibiotics, that share molecular composition with the nOPV2 vaccines.
9. Administration of immunoglobulins and/or any blood products since birth or planned administration during the study period.
10. Acute severe febrile illness at day of vaccination deemed by the Investigator to be a contraindication for vaccination (the child can be included at a later time if within age window and all inclusion criteria are met.).
11. Subject who, in the opinion of the Investigator, is unlikely to comply with the protocol or is inappropriate to be included in the study for the safety or the benefit-risk ratio of the subject.