CALIFORNIA ENCEPHALITIS VIRUS: AN EVALUATION OF ITS CONTINUED ENDEMIC STATUS IN KERN COUNTY, CALIFORNIA1

Abstract

Blood samples from 118 people living in Kern County, California in 1963, were tested for hemagglutination-inhibiting antibodies to California, Tahyna, and Calovo viruses. A high proportion of sera were positive to California and Tahyna viruses (39 and 51% respectively), and neutralization tests with California virus confirmed the specificity of reaction in most sera. The distribution of positive reactors by age and years of residence indicated that California virus was still endemic in this area. HAI antibodies to California virus were found in 7% of 608 sera from small mammals. Ten of 17 species were found with antibodies. As mammals are short-lived, this confirmed the endemic status of this virus. Only 6% of human sera reacted to Calovo virus (Bunyamwere group).