Long-term Immunogenicity and Safety of Fourth Administration of Boryung Cell-Culture Japanese Encephalitis Vaccineinj

Inclusion Criteria: * Parent/guardian (legally authorized representative) has given voluntary written consent to the subject's participation after being fully informed of the purpose, methods, risks, and benefits of the study. * Male and female children who have completed the primary 3 doses of JEV in the KD287-BR-CT-301study. * Male and female children reaching at least 6 years of age on the day of booster dosing of JEV. * Male and female children who are identified to be healthy based on physical examination and medical history. Exclusion Criteria: * Children who have acute febrile illness with tympanic temperature of ≥38.0 ℃ on the day of booster dosing of JEV. * Children who have moderate or severe acute disease (regardless of fever). * Children who have history of encephalitis, encephalopathy, cerebromeningitis, or convulsion. * Children who have received JEV (including live JEV) other than the investigational products administered in the KD287-BR-CT-301study. * Children who have had fever (≥ 40 °C) or systemic allergy within 48 hours after vaccination. * Children who have shown anaphylactic reaction to the investigational products administered in the KD287-BR-CT-301study or who are likely to be allergic to the ingredients of the investigational product. * Children who have been diagnosed with immunodeficiency such as acquired immune deficiency or who have family history of immunodeficiency. * Children who have received other vaccines within 28 days before booster dosing of JEV (vaccines to be administered according to the national vaccination program. * Children who have received immunosuppressive thera-py within 28 days before booster dosing of JEV. * There is a possibility that immune globulin preparations has not been excreted enough on the day of booster dosing of JEV if children have received such a product. * Children who are currently participating or planning to participate in other clinical stud-ies during the study period. * Other ineligible conditions judged at the discretion of principal investigators or subinvestigators.