Frequently Asked Questions


Mode of Spread

Prevention and Control


Disease Burden

1. What is Japanese Encephalitis ?

Japanese Encephalitis is a viral Zoonotic disease. It is caused by the Japanese Encephalitis(B) virus .It is an arbovirus  belongs to family Flaviviridae, Closely related to West Nile, St .Louis& Kunjin viruses.

These virus is present mainly in the birds & human being acquire this virus accidentally.  It is  febrile  illness involving the Central Nervous  System.

2. What are the signs and symptoms of Japanese Encephalitis?

The course of the disease can be conveniently divided into 3 stages:

A)    Prodromal stage.

B)     Acute encephalitic stage.

C)    Late convalescent stage.

Prodromal stage:

General malaise, abrupt onset of acute fever, head ache often accompanied with vomiting, ranges from 1 to14 days (average of 1 3 days).

Acute encephalitic stage:

Continuous fever (100 to 107 F), Stiff Neck, convulsions, Altered  sensorium, Focal CNS signs, Delirium, Stupor and finally progressing to coma.   Most death occurs in this stage

 Late convalescent stage.

Temperature returns to normal ,Neurological signs  stationary or tend to improve residual neurological deficit are common.

3. How Japanese Encephalitis is transmitted?

Transmitted by certain species of Cx.vishnui group of mosquitoes like Cx. Vishnui, Cx.pseudovishnui, Cx.tritaeniorhynchus etc. Enters the system by the bite of infected  mosquito.  The migratory birds carry the virus in them which is transmitted to man through the amplifier host (pig) by the masquitoes.

        4.      Where  do the Japanese encephalitis vector mosquitoes breed?

        They breed mainly in Paddy fields.

5. Is there specific treatment for  Japanese Encephalitis?

There is no specific treatment for this disease .The treatment is essentially supportive and symptomatic.

6. Is there a vaccine for Japanese encephalitis?


7.  What is the best way to prevent Japanese Encephalitis ?

The infection is transmitted only through bite of infected mosquito.  Human to human transmission is NIL.  The best way of prevention is personal protection (using mosquito net and repellants).

8. How to eliminate the breeding of mosquitoes ?

  1. Intermittent irrigation (following one dry day a week)  is the only way to eliminate the breeding of mosquitoes. 

        Using of neem coated urea in paddy fields.

Disease Burden