A cohort event monitoring to determine the adverse events following administration of mouse brain derived, inactivated Japanese Encephalitis vaccine in an endemic district in Sri Lanka.

Introduction of human immunization reduced Japanese Encephalitis (JE) cases dramatically in Sri Lanka. However, the increased reporting of adverse events following immunization (AEFI) affected vaccine acceptance by the community. Against this background, we describe the incidence of overall AEFI and incidence and profile of AEFI, thought to be causally related to the mouse-brain derived JE vaccine.