Japanese encephalitis vaccines

Abstract

Japanese encephalitis (JE) is a mosquito-borne viral infection and is the leading cause of viral encephalitis in Asia. Vaccination of humans is one of the most effective preventive strategies in endemic areas. Available JE vaccines belong to four different classes and all of them have been demonstrated to elicit adequate protective levels of neutralizing antibody. Live attenuated vaccine, based on the SA14-14-2 strain confers a high degree ofprotection after a single dose and is more cost effective and convenient for use. A live attenuated, recombinant (chimeric) JE vaccine is licensed for use in many Asian countries. WHO recommends integration of JE vaccine into national immunization schedules in areas where JE is recognized as a public health priority. Travellers from non-endemic countries having extensive outdoor exposure during the high transmission season or having extended stay should be offered pre-travel vaccination.