Serologic Studies of Spotted Fever Group Rickettsiosis Occurred in Muroto-City, Kochi Prefecture

In July and October of 1984, three patients with fever and rash were treated at the Muroto Clinic in Muroto-city, Kochi Prefecture.The sera collected from patients were subjected to the Weil-Felix test using the antigens standardized against the appropriate convalescent serum.A significantly high level of OX2 agglutinin and a more than fourfold rise in OX19 agglutinin titer were observed.Levels of complement fixing antibodies reactive to R. akari and R. rickettsii were found to be significant.In addition, the sera from three individuals were tested, who had been ill with similar symptoms and signs in October of 1983.Although the sera were collected later than one year after onset, two out of three samples showed positive reactions to the antigen of R.akari in complement fixation test.The serologic examinations proved that the disease was a spotted fever group rickettsiosis.