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Japanese Encephalitis

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 fatal outcomes.

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 bites.

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.