[Detection of humoral antibodies to species-specific and group ornithosis antigens in the dynamics of the infection].

The time course of antibody production to group- and species-specific antigens of ornithosis agent was studied by complement fixation (CFT) and hemagglutination-inhibition (HI) tests. In rabbits after a single intravenous inoculation of the ornithosis agent, antibody to the homologous species-specific antigen appeared in the peripheral blood 3--5 days after inoculation and reached maximum levels during the 1-st week, and to the group-specific antigen could be detected 3--5 days after inoculation but reached maximum titers only 3--4 weeks later. In practical serological diagnosis of ornithosis and other chlamydia infections, the group antigen is used which gives retrospective diagnosis at 10--14 days or later. The results of the study suggest that the use of CFT with the species-specific antigen will not only differentiate ornithosis from other chlamydial infections but also will permit early serological diagnosis of ornithosis.