Survey Of Seroprevalence Of Hepatitis B And Its Risk Factors Among General Population In Three Counties Of Jiangsu Province

Objectives: (1)To study the epidemic characteristics of HBsAg and analyze the risk factors a large sampled gernal population of Zhangjiagang, Danyang and Taixing counties in Jiangsu province, aiming to take further intervention measures to improve the comprehensive control level against hepatitis B. (2)To analyze the seroprevalence of hepatitis B by detecting HBsAg, Anti-HBs and Anti-HBc in a general population in order to provide scientific evidence for adopting suitable immunization strategies to reduce infection rate of HBV. (3)To compare domestic ELISA and Abbott CMIA in detecting HBsAg and Anti-HBs, and to evaluate the application value of domestic ELISA in the survey of the rate of chronic hepatitis B infection or the level of immunization..Methods: (1)With cluster random sampling in different regions, questionnaire survey was carried out to collect data and blood samples were collected to detect HBsAg by domestic ELISA. Univariate and multivariate logistic regression models were applied for data analysis. (2)One thousand nine hundred and thirty-six random serum samples were tested to detect HBsAg, Anti-HBs and Anti-HBc by Abbott CMIA. Results of domestic ELISA and Abbott CMIA in detecting HBsAg and Anti-HBs were compared, and the sensitivity and specificity of domestic ELISA were analyzed.Results: (1) The seropositive rates of HBsAg were 5.11%, 7.83% and 9.77% in Zhangjiagang, Danyang and Taixing respectively, and the standardized seropositive rates of HBsAg were 4.32%, 6.54% and 9.25%.The seropositive rate of HBsAg among people who born before programmed immunization over 18 years old were significantly higher than that among people under 18 years old, and the seropositive rate of HBsAg had an ascending trend in the age group from 18 to 40. In the age group over 18, the seropositive rate of HBsAg among people who had been inoculated hepatitis B vaccine was much lower than that among people who hadn't been inoculated. Male, hospitalization, tattoo, puncture, sharing needles and razors were the risk factors of HBV infection,while immunization was the protective factor. There was a significant negative correlation between blood donation and HBV infection. (2)The detecting results of three indicators (HBsAg, Anti-HBs and Anti-HBc) in the 1936 serum samples showed that the seropositive rates of HBsAg, Anti-HBs and Anti-HBc were 12.45%, 60.49% and 58.78%.There were 324 cases in which three indicators were all negative, and the rate was 16.74%. There were 221 cases of chronic HBV infection, and the infection rate was 11.41%. There were 464 cases, accounting for 23.97%, having protective antibody level against HBV. There were 907 cases of previous HBV infection, and the rate was 46.85%. The population in which three indicators were all negative were mainly concentrated in the age group from 15 to 40. The rate of chronic HBV infection and the rate of previous HBV infection both increased with age. The number of people who had protective antibody level against HBV decreased with increase of age. (3)The testing results of sensitivity and specificity of domestic ELISA showed that adjusted pairedχ2=21.16,P<0.0001 in the detection of HBsAg, so there was difference between domestic ELISA and Abbott CMIA, but kappa value=0.9373 which showed that the results of domestic ELISA and Abbott CMIA in detecting HBsAg were quite consistent. The sensitivity and specificity of domestic ELISA(HBsAg) were 88.38% and 100% respectively. In the detection of Anti-HBs, 85 cases showed inconsistent results. According to the results of Abbott CMIA, the sensitivity and specificity of domestic ELISA (Anti-HBs) were 95.47% and 95.95% respectively.Conclusion: The programmed hepatatis B immunization of newborns has achieved great success, seropositive rate of HBsAg in the children group has decreased significantly, and hepatatis B vaccine inoculation among adults can also obtain notable results.Therefore, while promoting immunization for children, it is necessary to further strengthen researches on hepatitis B immunization strategies for adults. The risk factors of HBV infection still existed widely, which indicated that the health promotion of HBV should be strengthened to enhance the ability of preventing HB infection of general population and further reduce the HBV infection rate. The specificity of domestic ELISA in detecting HBsAg was high. And generally there were no misdiagnosed cases when using domestic ELISA, but there existed a certain amount of omission diagnostic rate. Therefore, domestic ELISA could satisfy the need of screening chronic HBV infection in general population. The sensitivity and specificity of domestic ELISA in detecting Anti-HBs should be further improved.