Long-term Follow-up of Immunogenicity of a Single Dose of Japanese Encephalitis Chimeric Virus Vaccine (JE-CV) in Toddlers

Long-term Follow-up of Immunogenicity of a Single Dose of JE-CV in Toddlers in Thailand and the Philippines

This is a long-term follow-up of the persistence of immune response in participants who previously received a single dose of JE-CV at age 12 to 18 months in Study JEC02 (NCT00735644) . No vaccination was administered during the present long-term follow-up study.

Primary Objective:

• To describe the yearly persistence of humoral immune response to Japanese encephalitis after a single dose of JE-CV

Persistence of immune response will be determined in participants who previously received a single dose of JE-CV at age 12 to 18 months in Study JEC02 (NCT00735644). No vaccination will be given in this study.

Inclusion Criteria :

• Provision of Informed Consent Form signed by at least one parent or other legally acceptable representative, and by at least one independent witness if required by local regulations.
• Participant who was vaccinated with JE-CV in JEC02 trial and had a pre-vaccination blood sample at baseline in JEC02 trial.
• Participant and parent/legally acceptable representative able to attend all scheduled visits and comply with all trial procedures.

Exclusion Criteria :

• Receipt of any JE vaccine other than JE-CV during JEC02 trial and during the period up to inclusion in JEC05 trial.
• Planned participation in another clinical trial up to the first year of the follow-up in the present trial.