Japanese encephalitis vaccine
What is it for?
This vaccine protects you against the virus that causes Japanese encephalitis.
The virus is carried by mosquitoes, and mainly infects pigs and water birds that live in rural areas near flooded fields (where the mosquitoes breed). However, it can spread to people living nearby if they are bitten by a mosquito carrying the virus.
Japanese encephalitis is present during the summer or wet season (April to May until September to October) in northern Thailand, northern Vietnam, Korea, Japan, Taiwan, China, Nepal and northern India.
Japanese encephalitis occurs throughout the year in the tropical regions of Southeast Asia, Sri Lanka, southern India, and Bali.
It is also present in the rural areas near flooded fields in far North Queensland, the outer islands of the Torres Strait (from February to May), and Papua New Guinea.
Who should be vaccinated?
The vaccination is recommended for children (1 year and older) and adults visiting places where Japanese encephalitis is present who:
- will stay for 1 month or longer
- will travel during the wet season
- frequently visit these countries, do outdoor activities there, or stay in accommodation that is not mosquito-proof
- will spend 1 year or more in Asia (except Singapore)
- live on the outer islands in the Torres Strait
- will visit the outer islands of the Torres Strait for 1 month or more.
People travelling to Asia and other tropical regions should take appropriate measures to avoid mosquito bites.
Anyone who needs to have the Japanese encephalitis vaccine can be vaccinated at their own cost. Visit your doctor at least 2 weeks before you travel.
If you have to travel to a country where Japanese encephalitis is present and you are at risk of infection, you can have the vaccination while you are pregnant. If you are not vaccinated, infection during the first 6 months of pregnancy may cause miscarriage.
Read more about what vaccines you can have if you are pregnant.
Women who are breastfeeding
There is no known risk to your baby if you are vaccinated with the Japanese encephalitis vaccine while you are breastfeeding.
Women who are breastfeeding can be vaccinated with any vaccine except the yellow fever vaccine.
Common side effects of the Japanese encephalitis vaccine (that may affect 1 to 10 in every 100 people) include:
- soreness, redness and swelling at the injection site
- fever (a temperature that is higher than 38.5°C)
- muscle aches (myalgia).
Read more about vaccine side effects and safety.
Who can I ask about side effects?
If you’re concerned that you or your child may have had side effects related to a vaccine, seek medical advice. To report and discuss possible side effects, call the Adverse Medicines Events (AME) Line on 1300 134 237 from anywhere in Australia (Monday–Friday, 9am–5pm AEST).
- Rossi S, ed. eAMH [online]. Adelaide: Australian Medicines Handbook, January 2013.
- Australian Government Department of Health and Ageing. Office of Health Protection. 4.8 Japanese encephalitis. In: The Australian Immunisation Handbook, 10th edn. www.immunise.health.gov.au/internet/immunise/publishing.nsf/Content/handbook10-4-8