Short report: absence of protective neutralizng antibodies to West Nile virus in subjects following vaccination with Japanese encephalitis or dengue vaccines.

Protection of individuals against West Nile (WN) encephalitis is an emerging concern in the United States and Europe. We investigated whether immunization with licensed inactivated Japanese encephalitis (JE) vaccine or experimental live attenuated dengue vaccines resulted in induction of cross-neutralizing antibodies against WN virus. Protective neutralizing antibody titers to WN virus were not detected in any volunteer despite successful immunization to related flaviviruses. Vaccination against JE or dengue is unlikely to prevent WN virus infection but may still protect against disease.