Japanese encephalitis is a very serious infectious disease caused by Japanese encephalitis virus (JEV), which belongs to the family Flaviviridae and is maintained in a zoonotic cycle involving the Culex species of mosquitoes and vertebrate hosts. Endemic to most of Asia and to certain regions of the western Pacific, JEV frequently causes severe neurologic sequelae or death in infected humans. This enveloped virus possesses a positive-sense single-stranded RNA genome packaged in a spherical nucleocapsid. The genome contains a single open reading frame that encodes for a polyprotein, which is further cleaved into three structural (C, prM, E) and seven non-structural proteins (NS1, NS2A, NS2B, NS3, NS4A, NS4B, NS5). |