ABSTRACT
A possibility was shown of using the phospholipid group-specific antigen of the ornitosis causative agent in the capacity of a hemosensitin for conducting the indirect hemagglutination test (IHAT). There was revealed a direct proportional relationship between the sensitizing activity and the complement fixing properties of the antigens obtained. A method of sorption of this antigen on the tannin-treated erythrocytes and the optimal parameters of conducting the test with it were elaborated. A sufficiently high sensitivity and specificity of the IHAT was revealed as a result of parallel titration of hetero-and homologous sera in the complement fixation test and in the IHAT. The suggested test can be successfully used for the diagnosis of ornithosis.