[The detection of the antigens of influenza viruses A and B in the blood of healthy donors].

Blood clots and sera were obtained from donors at a Moscow city transfusion clinic during 1984-1988 and tested by indirect solid-phase enzyme immunoassay with original test-sera to hemagglutinating antigens of influenza A (H1 and H3) and B viruses. Examinations of 1714 blood samples demonstrated hemagglutinating antigens of different specificity (from 0.8% to 35%), the detection rate of one or another antigen correlating with the epidemic activity of influenza virus serovariants A and B. The virus-specific antigens, however, were almost regularly detected in the blood of healthy subjects in the interepidemic seasons as well. The highest number of positive results was observed in tests with blood clot or serum. The results indicate the principal capacity of influenza virus to persist in apparently normal subjects.