Japanese Encephalitis

Japanese Encephalitis is a serious disease and is endemic throughout most of Asia, primarily in rural areas. The virus is transmitted by the Culex tritaeniorhynchus mosquito which feed outdoors from dusk to dawn, breeding in rice fields, water and marshes.


Signs and Symptoms

Most infections are mild (fever and headache) or without obvious symptoms, but approximately 1 in 300 result in severe illness.  Severe disease is charactertised by:

§  rapid onset of high fever

§  headache

§  neck stiffness

§  disorientation

§  coma

§  seizures

§  spastic paralysis


The fatality rate can be as high as 30%. Of those who survive, 20-30% suffer permanent intellectual, behavioural or neurological problems such as paralysis, recurrent seizures or the inability to speak.

Mosquito bite prevention is vital, however vaccination should be considered for those who are considered to be at significant risk.

These include:

§  Prolonged stays (over 1 month) or frequent shorter stays in rural farming areas in countries at risk

§  Travel to specific areas with current known epidemics

§  Shorter rural visits by persons with extensive outdoor exposure (eg; hikers, cyclists, bikers and adventure travellers)


The vaccination takes a minimum of 10 days to become effective and can be quite expensive, so discuss your options with our specialist.