[A community-based seroepidemiological survey of hepatitis B among adults in Chaoyang district, Beijing]

To understand the positive rates of hepatitis B surface antigen (HBsAg) and surface antibody (anti-HBs) among adults aged ≥18 years in communities in Chaoyang district, Beijing.

HBsAg and anti-HBs were tested with ELISA reagents for participants in the Community Diagnosis Survey (3 000 person were sampled in each community according to the age and sex distribution of the residents) in all 42 communities in Chaoyang district by Beijing Center for Disease Control and Prevention (CDC) and Chaoyang CDC. The data of 35 communities in which at least 1 000 adults were tested were analyzed.

A total of 78 100 adults were tested for HBsAg and anti-HBs in the 35 communities. The crude positive rate of HBsAg was 2.24% (95% CI: 2.13%-2.34%). The highest age-specific HBsAg positive rate was 3.00% (95% CI: 2.56%-3.44%) for those aged 40-44 years and the lowest age-specific HBsAg positive rate was 1.69% (95% CI: 1.29%-2.09%) for those aged 18-24 years, respectively. A obvious difference in community- based HBsAg positive rate was founded with the highest of 10.68% (95% CI: 9.43%-11.94%) and lowest of 0.24% (95% CI: 0.13%-0.38%). HBsAg positive rate was significantly lower in local residents than in participants with household registered in other provinces (1.97% vs. 2.98%, P<0.01), but the sex specific difference in HBsAg positive rate was relatively smaller (2.45% in males and 2.07% in females, P<0.01). The multivariate logistic regression analysis showed that age, community, occupation, residence status and sex were all associated with positive rate of HBsAg (P<0.01). The overall positive rate of anti-HBs was 30.85% (95% CI: 30.53%-31.18%), and the highest was 38.10% in age group 18-24 years (95% CI: 36.58%-39.61%) and the lowest was 28.88% in age group 75- years (95% CI: 27.62%-30.15%), respectively. Up to 67.02% of the subjects were both HBsAg and anti-HBs negative (95% CI: 66.69%-67.35%), and the age specific difference was not significant. But significant differences in anti-HBs positive rate and the negative rate of both HBsAg and anti-HBs were found across communities.

The overall positive rate of HBsAg was at a moderate low level among adults in Chaoyang, but the age specific positive rate was high in the middle-aged and the population specific positive rate was high in participants with household registered in other provinces, therefore, the prevention and control of hepatitis B in Chaoyang should be focused on the middle aged people and participants with household registered in other provinces. The community specific differences in the positive rate of HBsAg and anti-HBs across communities need to be further studied.