Immunogenicity and Safety Evaluation of Different Sequential Immunization Strategies by Sabin IPV and bOPV in Chinese Infants

Inclusion Criteria: * Parent/legal acceptable representative is willing and able to understand the protocol requirements and provide informed consent. * Participant is aged ≥ 60 days to ≤ 75 days. * Participant without preventive inoculation of polio vaccine and previous history of Polio. * Subject and parent/guardian able to attend all scheduled visits and comply with all trial procedures. * Body temperature ≤ 37.5℃. Exclusion Criteria: * Known allergy to any constituent of the vaccine. * Known acute illness, severe chronic disease, acute exacerbation of chronic disease and fever. * Known or suspected impairment of immunologic function, or receipt of immunosuppressive therapy or immunoglobulin since birth. * Reported the history of allergies, convulsions, epilepsy, mental illness and brain disease and clear serious systemic reaction. * Known bleeding disorder. * Receipt of the whole blood, blood plasma or immunoglobulin before the trial vaccination. * Reported the history of acute illness had need systemic antibiotics or antiviral treatment of infections in the 7 days preceding the trial vaccination. * An acute illness with or without fever (temperature ≥ 38.0℃) in the 3 days preceding enrollment in the trial. * Participation in any other intervention clinical trial. * Any condition which, in the opinion of the investigator, would pose a health risk to the subject or interfere with the vaccine.