Sero-epidemiological analysis of hepatitis B in children in Shenzhen

Objective To better understand the epidemiological status of hepatitis B among children in Shenzhen and to evaluate the protective effect of HBV vaccine.Methods A total of 1 653 children aged from 1-14 years were selected by using multi-stage cluster random sampling method in the study.A questionnaire survey was conducted and blood samples were collected to detect HBsAg and anti-HBs as well as anti-HBc.Results The overall positive rate of HBsAg,anti-HBs,anti-HBc and the infection rate of HBV were 2.06%,74.53%,5.32% and 9.62%.Compared to unvaccinated children,the positive rate of anti-HBc and HBV infection rate among vaccinated children decreased from 10.87% to 4.60% and from 73.98% to 5.41%(χ2=7.14,457.83,P0.01) respectively,while there were no big differences of HBsAg and anti-HBs positive rates between vaccinated and unvaccinated children.Among children vaccinated in 3 years,none of them was found HBsAg positive,while the positive rates of anti-HBs,anti-HBc and HBV infection rate were 73.71%,2.0% and 2.0%.These numbers increased to 5.46%,79.23%,8.74% and 11.48% among children vaccinated 7 to 9 years age,except the positive rate of anti-HBs.All showed differences in terms of vaccination time(χ2=29.53,36.88,43.75,P0.01).Conclusions Keeping high pitching rate of hepatitis B vaccine in children can effectively reduce the hepatitis B infection rate.Meanwhile,reinforcing the application of hepatitis B vaccine is one of the most important strategies to prevent and control hepatitis B endemic.