California Group Arboviruses: Immunodiffusion Studies

Differentiation of members of the California group of arboviruses was accomplished using the double diffusion in gel technique of Ouchterlony. Eight antigenic subgroups were defined on the basis of unique antigenicities. These groupings confirmed the individuality of isolates described in the literature and allowed classification of new isolates. Unique, yet identical, patterns of antibody specificity were found in convalescent sera of 11 individuals with central nervous system disease.