Lot-to-lot Consistency Trial of Japanese Encephalitis Live Attenuated SA 14-14-2 Vaccine

Inclusion criteria

• Infant's parent(s) or legal guardian(s) willing to provide signed informed consent.
• Healthy infants aged 10 to 12 months at enrolment residing in Matlab Health and Demographic Surveillance System (HDSS) intervention area who have completed all doses of Expanded Programme on Immunization (EPI) immunizations at least 4 weeks prior to enrolment: Bacillus Calmette-Guerin vaccine (BCG), Diphtheria-pertussis-tetanus vaccine (DPT), Hepatitis B (HBV), Haemophilus influenzae type (Hib), oral polio vaccine (OPV) and measles

Exclusion criteria

• Acute medical illness with or without fever within the last 72 hours or an axillary temperature (≥ 37.5°C ) at the time of vaccination.
• Use of antibiotics or antipyretics within the last 72 hours prior to enrolment.
• Severely or moderately malnourished infants (<-3 Z score).
• History of prematurity (< 36 weeks of pregnancy).
• Underlying medical condition such as failure to thrive, inborn errors of metabolism, bronchopulmonary dysplasia, or any major congenital abnormalities requiring surgery or chronic treatment.
• History of serious chronic disease (e.g., cardiac, renal, neurologic, metabolic, rheumatologic, hematologic, or bleeding disorder).
• Known or suspected impairment of immunologic function.
• History of documented or suspected encephalitis or meningitis.
• History of seizures, including history of febrile seizures, or any other neurologic disorder.
• History of JE infection.
• Prior receipt of a JE vaccine.
• Received measles vaccine within 4 weeks prior to, or scheduled to receive a vaccination during, the conduct of this trial.
• Prior or anticipated receipt of immune globulin or other blood products, or injected or oral corticosteroids or other immune modulator therapy within 6 weeks of administration of the study vaccine.
• Serious adverse reactions (e.g. urticaria, angioedema, shock, breathlessness following vaccination or any life threatening condition) with any previous EPI vaccine.
• Unable to attend the scheduled visits or comply with the study procedures.
• Enrolled in another clinical trial involving any therapy.
• Any condition that in the opinion of the investigator, would pose a health risk to the child, or interfere with the evaluation of the study objectives.