skip to Main Content

What is Japanese Encephalitis?


Japanese encephalitis (JE) is a serious and life threatening brain infection spread through the bite of an infected mosquito. Over 50,000 cases are reported annually and 1 in every 50-1000 people will develop symptoms.

Initial symptoms appear 5-15 days after infection and include headache, nausea, fever, vomiting, diarrhea and changes in behavior. These symptoms can progress to an inflammation of the brain which can cause permanent brain damage or physical disability(occurring in 30-35%  of cases) and death (fatality rate is 30-40%).

 There is no known cure for the disease.

 Where is it found?

Japanese encephalitis is common in Vietnam, Thailand, Korea, India, Japan, Indonesia and Papua New Guinea.

Risk is greatest in rural areas and changes depending on the season.  However the virus can also be contacted in or near cities.

Travelers staying in risk areas for less than 30 days are generally at low risk for infection.

Japanese Encephalitis

Discuss with a travel nurse prior to your trip to address any concerns you may have.

Is there a preventative vaccine?

The vaccine (Ixiaro) for JE virus is given in a series 2 doses given 4 weeks apart. It is recommended for those 18 years of age and older.

Vaccination for those travelling to risk areas depends on length of trip, season, and activities during stay.

Prevention should also include insect precautions during outdoor activities from dusk to dawn when mosquitoes are more prevalent.

Are there any potential side effects?

Side effects are generally mild and may include pain and swelling at injection site, fever, headache.

These symptoms, if they occur, usually only last a short period of time.

Once infected what are the treatments?

There is currently no treatment for the disease, it can only run its course.

Please also see our page on Protection Against Insect Bites

Back To Top