Murray Valley Encephalitis Virus: Its Serological Relationship to the Japanese-West Nile-St. Louis Encephalitis Group of Viruses

Abstract

An agent isolated by Australian workers in 1951 and designated as Murray Valley encephalitis virus has been characterized antigenically by the means of neutralization and complement-fixation tests and cross vaccination experiments. The MVE virus appears to be a new member of the JE-WN-SLE group of agents, more closely related antigenically to JE than to WN and SLE. Results of neutralization tests on sera of Japanese Nationals suggest that MVE virus is absent from Japan, or that it infects fewer people than JE virus. Although half the sera tested contained MVE antibodies, these were invariably obtained from persons with large amounts of JE antibody and the MVE effect could probably be attributed to prior JE infection. When 14 strains of supposed JE virus isolated in the Far East were re-examined in neutralization tests with JE and MVE immune rabbit sera of known specificity, all strains reacted as JE and none could be re-designated as MVE virus.