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Seroprevalence of hepatitis B virus markers in individuals for physical examination in West China Hospital, China.

BACKGROUND
Hepatitis B virus (HBV) is the major cause of chronic hepatitis,cirrhosis, and hepatocellular carcinoma. The global epidemiological scenario of HBV infection has been changing rapidly over the last two decades due to an effective immunization programme initiated by the World Health Organization. The objective of this study is to estimate the prevalence of HBV in apparently adult people who were taken health examination in our Hospital.


METHODS
A cross-sectional seroprevalence analysis of hepatitis B virus infection was performed in 12037 adult residents (aged > or =18 years) in Chengdu, who visited Health Examination Center of West China Hospital of Sichuan University for routine medical check-up during the period from March to December 2008. A structured medical form was used to collect data on demographic characteristics and risk factors. ELISA was used to test sera for HBV markers. Descriptive and logistic regression models were used for analysis.


RESULTS
A total of 12,037 urban residents were involved. Prevalence of positive HBsAg was 6.1%, lower than the level of national seroepidemiological survey in (7.18%). Among HBsAg negative people, anti-HBs and anti-HBc was 60.2% and 13.6% respectively. There was a maximum between 18 to 29 years of age (61.8%) in anti-HBs positive people. Multivariate conditional logistic regressive analysis showed that, except for blood and vertical transmission, factors of male gender (OR, 1.876; 95% CI, 1.519-2.316; P < 0.001) and alcohol intake (OR, 0.689; 95% CI, 0.571-0.832; P < 0.001) were associated with a higher risk of positive HBsAg.


CONCLUSIONS
Among the medical examination people in Chengdu, HBsAg positive rate was lower than the national general population, the epidemiological characteristics of hepatitis B has been changed, because of vacination policies to the newborn; therefore, the necessity to continue to carry on the vaccination program.