Oral immunisation of mice with live Japanese encephalitis virus induces a protective immune response

This study was undertaken to evaluate the efficacy of oral immunisation of mice with live Japanese encephalitis virus (JEV). Swiss albino mice were im munised with JEV by the peroral (PO). intraperitoneal (IP) and the subcutan eous (SC) routes on days 0, 7 and 14 using either mouse brain derived immun ogen (MBDI) or cell culture derived immunogen (CCDI). Oral immunisation of mice evoked high anti-JEV antibody titres by ELISA (Geometric mean titres o f 5065 with CCDI and 8854 with MBDI). Moreover, the orally immunised mice s howed 76.7% protection with MBDI and 70% with CCDI against intracerebral ch allenge with a lethal dose of JEV. This study demonstrates for the first ti me that oral immunisation of mice with live JEV generates a brisk, protecti ve immune response. The results of this study suggest that oral immunisatio n with JEV holds promise for the future. (C) 1999 Elsevier Science Ltd. All rights reserved.