Analysis on alternation trend of antibodies in tularemia patients from 1985 to 2005

  Objective   To study the maintainable time of humoral immunity against Frencisella tularensis after infection, influence factors and the recessive infection situation in healthy people.

  Methods   Thirty-one subjects with acute tularemia and the same area healthy people were studied for antibodies to Frencisella tularensis by using Immuno-Chromatographic Assay(ICA)in third week(Jan., 1986), sixth month(July, 1986), second year(1987), third years(1988), sixth year(1991), seventh year(1992), eighth year(1993), ninth year(1994), twentieth year(2005).Special antibody were detected in the cohort study.Titers of > 1B40 were defined as positive.And the subjects were retrospectively studied in 2005.

  Results   The GMT of subjects decreased from 11890.00(in 1986)to 46.94(in 2005).The rate of decay was 59.1%.Acorrelation was known between the titer of earlier period and that of the latephase(r=0.659, P < 0.05).There were no statistically significant difference between the content of questionnaire and the late-phasetiter.The control group was negative result during 20 years.

  Conclusion   Special antibody in partial patients can last for a long time with a gradual reducing trend.The titer of the earlier period influence sig nificantly that of the late-phase without other factors.And there is no recessive infection in the healthy people.