STUDIES ON JAPANESE B ENCEPHALITIS VIRUS (1)

PRESERVATION OF JAPANESE B ENCEPHALITIS VIRUS BY LYOPHYLIZATION

Abstract

1) The Japanease B Encephalitis virus prepared from the brain of the infected mouse was liophilized using dryice and alcohol in the vacuum degree 10^-3mmHg, thereafter kept in 4°-8°C. In such condition, the virus maintain its activity for eighteen to thirty months.
2) If the material kept in glycerol-saline solution for some days before lyophylization, the virus could similarly preserved its activity.
3) The five or twenty percent solution of dry skin-milk was suitable to the medium for lyophylization.