PREVALENCE OF YERSINIA ANTIBODIES IN BLOOD-DONORS

Agglutinins titers against Y. enterocolitica 0:3, 0:5, 0:9 and Y pseud otuberculosis I were determined by the microagglutination method in 77 7 blood donor sera. Titers of less-than-or-equal-to 1/10 were observed in 93.5% of the subjects for Y. enterocolitica 0:3, in 87.8% for Y. e nterocolitica 0:9 and in 95. 1% for Y enterocolitica 0:5 and for Y pse udotuberculosis 1. Low level titers (1/10 - 1/20) were found in 11.4% to 23.1%. Titers of greater-than-or-equal-to 1/40 were observed in 1.7 % for Y enterocolitica 0:3, in 1.4% for Y enterocolitica 0:5, in 5.1% for Y enterocolitica 0:9 and in 1.2% for Y. pseudotuberculosis I. Tite rs of greater-than-or-equal-to 1/80 were seen in 0.2% for Y. enterocol itica 0:3, in 0.1% for Y enterocolitica 0:5 and in 1.3% for Y. enteroc olitica 0:9. Only in one donor's serum was a titer of 1/160 against Y enterocolitica 0:9 found. The upper limit of normal titer at 15% cutof f level against Yersinia antigens, found in blood donor sera by the mi croagglutination test, was 1/10.