Japanese encephalitis virus (JEV) is one of the most important causes of Viral encephalitis prevalent all over the world including India. It is closely related to West Nile, Saint Louis and Murray Valley encephalitis viruses. Molecular testing assists in early diagnosis of JEV prior to appearance of antibodies in blood. Most human infections are asymptomatic or result in only mild symptoms. However, a small percentage of infected persons develop Encephalitis with sudden onset of headache, high fever, disorientation, coma, tremors and convulsions.