Hemagglutination Test in Tularemia

[摘要] Agglutinin and hemagglutinin titers were determined in 59 cases of laboratory-acquired tularemia occurring in 56 cases of laboraotry-acquired tularemia occurring in 56 vaccinated persons. A 4-fold rise in agglutinins was observed, on the average, on the 19th day of illness and the mean peak titer of 1:1280 sometime during the second or third month. Thereafter, agglutinins fell slowly and were detectable as long as 12 years after infection, closely paralleling the response seen in naturally-occurring tularemia.Hemagglutinins reached diagnostic levels on the 11th day, on the average, and the mean peak titer of 1:10,240 occurred during the second month. Hemagglutinins also persisted in the serum for years, at somewhat higher levels than agglutinins.By the end of the second week of illness, 38% of patients had 4-fold or greater increases in hemagglutinin titer, but only 15% had had a diagnostic rise in agglutinins.In 26 cases, sera were collected frequently during the acute phase of illness. In 14, a diagnostic level of hemagglutinins occurred earlier, and in the other 12 4-fold increases of both antibodies occurred at the same time. In no case did agglutinins rise earlier.In eight patients there was no change in antibody titer during the course of illness. This was possibly due to prior elevation from booster vaccination within 6 weeks of onset of disease, or reinfection (proved or probable). In one case there was a rise in hemagglutinins although agglutinins did not change.

[学科分类] 生物科学（综合）