Japanese encephalitis is a viral infection transmitted by mosquitos.
It occurs in many Asian countries, and the risk of transmission
depends on the geographic region being visited and the time of year.
Transmission is facilitated in rural, agricultural locations, but
may potentially occur near or occasionally within certain urban
centers. Many infections do not produce symptoms; however, persons
that acquire the disease may have severe neurological and possibly
The risk to short-term travelers and persons who confine their
travel to urban centers is very low. Expatriates and travelers living
for prolonged periods in rural areas where Japanese encephalitis
occurs are at greatest risk. Travelers with extensive unprotected
outdoor,evening, and night time exposure in rural areas may be at
high risk even if their trip is brief. Travelers are advised to
take personal protective measures, including
staying in screened or air-conditioned rooms, using bednets when
such quarters are unavailable, using insect sprays and mosquito
repellents as needed, and wearing protective clothing to avoid mosquito
Primary vaccination against Japanese encephalitis includes three
doses. Ideally, the second and third doses should be given 7 and
30 days, respectively, after the first dose. The vaccine series
should be completed at least ten days prior to departure. Accelerated
vaccine schedules may be used in travelers with unavoidable time
constraints; however, the effectiveness of such administrations
may not provide optimal protection. The duration of protection is
not precisely known, but preliminary data indicate that it may persist
for at least three years.
If you wish to receive Japanese encephalitis vaccine, please call
us for a clinic appointment.