Mosquito borne flavivirus.
The leading cause of encephalitis in Asia.
Predominantly a disease of rural Asia and parts of the Western Pacific, particularly where there is rice culture and the coexistence of pig farming.
In endemic countries most adults have protective immunity.
Primarily a disease of children.
Travelers of any age may acquire infection.
Transmission occurs primarily in the summer and fall in temperate areas, and in tropical and subtropical areas.
Transmission varies with irrigation practices, and heavy rains.
Risk for most travelers to Asia is low, with estimated cases in the non-endemic areas, occurring in less than one case per 1 million travelers.
Travelers with prolonged stays in rural endemic areas are at greater risk.
Less than 1% of infections result in clinical disease.
The case fatality ratio of approximately 30% and causes neurological sequelae in approximately 50% of survivors.
No specific treatment exists.
Prevention is paramount, and the includes the use of personal protective measures to reduce the risk for mosquito bites, including bed nets, insect repellents, protective clothing, and avoidance of outdoor activity.
Vaccination is recommended for individuals with long stay travel to an endemic rural area.