Japanese encephalitis

How is Japanese encephalitis transmitted?

By rice field breeding mosquitoes (primarily the Culex tritaeniorhynchus group) that become infected with Japanese encephalitis virus (a flavivirus antigenically related to St. Louis encephalitis virus).

How do people get Japanese encephalitis?

By the bite of mosquitoes infected with the Japanese encephalitis virus.

What is the basic transmission cycle?

Mosquitoes become infected by feeding on domestic pigs and wild birds infected with the Japanese encephalitis virus. Infected mosquitoes then transmit the Japanese encephalitis virus to humans and animals during the feeding process. The Japanese encephalitis virus is amplified in the blood systems of domestic pigs and wild birds.

Could you get the Japanese encephalitis from another person?

No, Japanese encephalitis virus is NOT transmitted from person-to-person. For example, you cannot get the virus from touching or kissing a person who has the disease, or from a health care worker who has treated someone with the disease.

Could you get Japanese encephalitis from animals other than domestic pigs, wide birds or from insects other than mosquitoes?

No. Only domestic pigs and wild birds are carriers of the Japanese encephalitis virus.

What are the symptoms of Japanese encephalitis?

Mild infections occur without apparent symptoms other than fever with headache. More severe infection is marked by quick onset, headache, high fever, neck stiffness, stupor, disorientation, coma, tremors, occasional convulsions (especially in infants) and spastic (but rarely flaccid) paralysis.

What is the incubation period for Japanese encephalitis?

Usually 5 to 15 days.

What is the mortality rate of Japanese encephalitis?

Case-fatality rates range from 0.3% to 60%.

Is there any vaccine available against JE virus in India?

Inactivated Mouse Brain-Derived JE Vaccine is available against JE in India.  The Vaccine in manufactured at Central Research Institute, Kasauli, Himachal Pradesh.

Source: National Vector Borne Diseases Control Program, Ministry of Health & Family Welfare