Travel vaccine
Japanese Encephalitis Vaccine
The Japanese encephalitis vaccine protects against a mosquito-borne brain infection found in parts of Asia, recommended for some longer or rural trips.
What it protects against
It protects against Japanese encephalitis, a viral infection spread by mosquitoes in parts of Asia and the western Pacific that can, in a small number of cases, cause serious brain inflammation.
Who it's for
Travellers spending longer periods, or visiting rural and farming areas, in affected parts of Asia during the transmission season, and some people at occupational risk.
How it works
It contains inactivated virus, given as two doses, prompting protective antibodies before travel.
Safety
Safety and side effects
It is safe and well tolerated, with common effects being soreness at the injection site, headache and muscle aches. Mosquito-bite avoidance remains important alongside the vaccine.
Education and reference only. This is general information, not a personal recommendation, and does not list doses — follow the current NHS schedule and your clinician's advice. Seek urgent help for signs of a serious allergic reaction after any vaccine.
Answers
Japanese Encephalitis Vaccine: frequently asked questions
Who needs the Japanese encephalitis vaccine?
It is mainly for travellers spending longer periods or visiting rural areas in affected parts of Asia, especially during the mosquito season. A travel clinic can assess whether your trip warrants it.
Does the vaccine mean I don’t need to avoid mosquito bites?
No. No vaccine is completely effective, and mosquitoes in these areas can spread other diseases too, so avoiding bites with repellent, nets and covering up remains essential.
Related
Other travel vaccines
Sources
Where this is drawn from
- NHS — Vaccinations
- UK Health Security Agency (UKHSA) — the Green Book
- WHO — immunization
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