Japanese encephalitis is viral infection of the brain transmitted by infected Culex mosquitoes that bite infected animals and then humans.
JE virus is the most common vaccine-preventable kind of encephalitis in Asia, occurring throughout most of Asia and parts of the Western Pacific.* Transmission principally occurs in rural agricultural areas, often associated with rice cultivation and flood irrigation.* In some areas of Asia, these ecologic conditions may occur near, or occasionally within, urban centers.* In temperate areas of Asia, transmission is seasonal, and human disease usually peaks in summer and fall.* In the subtropics and tropics, seasonal transmission varies with monsoon rains and irrigation practices and may be prolonged or even occur year-round.*
For geographic distribution of Japanese encephalitis, please visit:
http://wwwnc.cdc.gov/travel/content/yellowbook/2014/map_3-08-small.png
Any traveller who develops one or more of those symptoms should see a doctor immediately.
The case-fatality ratio is approximately 20%–30%. Among survivors, 30%–50% have serious neurologic, cognitive, or psychiatric sequelae.* In other words, a third of those who become infected die and half the survivors become seriously disabled.
Always, the most important step in prevention is avoidance of mosquito bites. For more information see our Mosquito Safety section.
A safe and effective vaccine for Japanese encephalitis is available at our travel clinic.
Please Note:
- The information in this page is for educational purposes only. It is not to substitute for a formal travel consult with your travel doctor.
- If you have health insurance offered to you through work or school you may be covered for vaccines. At time of payment, we will provide you with an invoice (with the unique DIN for each vaccine) so you can claim your expenses back from your insurance company.this vaccine is not covered by OHIP for travel purposes.
- Always seek immediate medical advice if you get sick abroad or after you return.
- regardless of vaccination status, Mosquito safety measures should be always implemented.