A strain of Japanese encephalitis (JE) virus (strain 822199), originally isolated from human brain of a fatal JE case from Kolar, Karnataka State (India) in 1982, showed unusually high peripheral virulence in adult Swiss mice. The strain produced encephalitis and high virus titres were recorded both via intraperitoneal and subcutaneous routes in adult Swiss mice. The peripheral virulence of the strain 822199 was comparable with that of a Chinese (Beijing P3) strain of JE virus which was not depicted by any of the other Indian strains of JE virus tested so far. Its immunotyping employing monoclonal antibodies (MAbs) raised against ‘E'glycoprotein of JE virus and those of WN virus revealed that strain 822199 belonged to group II of JE virus which have lost partially some of its virus specific and protective epitopes. Thus, strain 822199 is the first Indian JE virus strain depicting high peripheral virulence and may be useful for studying JE pathogenesis in mice in relation to frequent resurgence of JE in some of the affected areas in India.
Japanese encephalitis virus, an Indian strain 822199, peripheral virulence, adult Swiss mice
