Japanese Encephalitis (JE) is a mosquito-borne viral infection endemic in many parts of Asia. While many cases are subclinical, complications can be severe and death may occur. Persons at risk should consider receiving the JE vaccine.


Countries at risk:

(1) Japan

(2) Korea

(3) parts of China

(4) Thailand

(5) India

(6) Indonesia

(7) Philippines

(8) Cambodia

(9) Myanmar


Transmission period: May through October


People who should consider receiving the JE vaccine

(1) persons living in an endemic region

(2) traveler to an endemic region during the transmission season, especially if the trip will include rural destinations and/or if spending more than 4 weeks in the region

(3) soldier assigned to an endemic region


In addition, persons traveling to the endemic areas should also take precautions to minimize mosquito bites.



(1) previous significant reaction to the vaccine

(2) allergy to a component of the vaccine


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