Epidemiological Profile of Encephalitis Virus

Japanese encephalitis also called as Japanese B encephalitis is a vector bone infectious disease caused mainly by infected culex mosquitos. It is more common in rural and agricultural areas, predominantly seen in the Asia-Pacific region. Japanese encephalitis virus (JEV) has the potential to spread worldwide with increased rates of morbidity and mortality. Generally, most cases of infection cause subclinical febrile illness whereas potentially severe cases show a major impact on the brain causing its swelling and disorientation which makes it fatal. In the prodromal phase symptoms such as mild fever, chills, muscle pain, vomiting, diarrhea and meningitis are common. During the acute phase of infection, the patient manifests symptoms like seizures, reduced consciousness, parkinsonian syndrome and may result in a coma. JEV MAC DOT tests are used in the diagnosis of infected patients. No specific anti-JEV drugs are available to date. Many studies have been conducted to identify the target molecules that are responsible for JEV's progression. Specific targets have been identified that uncovered the mechanism of the drug based on how it works through pathology and virological studies. Few JEV vaccines have been discovered, though their global usage is narrowed due to their side effects and their high cost. It has an estimated incidence of >60, 000 cases and 20,000 deaths annually. In order to alleviate acute infections no proper antiviral drugs are available other than the supportive care given for symptoms. Quarantine and movement control are practiced as preventive measures to avoid exposure to JEV and susceptible animals. In this chapter, the current knowledge of the etiology, pathogenesis and virological studies of the lethal disease as well as efforts made for vaccine development against JEV have been summarized with a view to control the spread of the catastrophic and fascinating disease.