ABSTRACT
@# Objective To evaluate the risk of hepatitis B virus(HBV) infection among preschool children who were the non-responders to hepatitis B vaccine in future. Methods A prospective cohort study was conducted. Children aged 2 to 5 years were selected from 64 kindergartens.These children were inoculated three doses of hepatitis b vaccine at 0, 1 and 6 months after birth. Hepatitis B surface antigen (HBsAg)and Hepatitis B surface antibody (anti-HBs)were detected during the period from March to May 2015. The children who were HBsAg negative were enrolled in the study. The subjects were divided into exposure group (anti-HBs negative) and control group (anti-HBs positive) . The follow-up began on June 1, 2015 and ended on June 1, 2016. Serum HBsAg of children in the cohort was then collected and detected from June 1 to 30, 2016. At the end of the study, the HBsAg positive rates between two groups were compared. Results 83 children who received hepatitis B vaccine again during the follow-up period were excluded from 1 907 non-responders. The actual number in non-responders group was 1 824. 151 children were lost at the end of the study. The actual number of follow-up was 1 673 and 5 children were found to be positive for HBsAg and the infection rate was 0.30% (5/1673). In the respondent goup, 2 054 were enrolled and followed. Finally, 140 children were lost and none of the remaining 1 914 people were HBsAg positive at the end of the study. HBsAg positive rate was higher in the non-responder group than in the responder group (P=0.023). Conclusion There is a risk of HBV infection in the children who are non-responders to hepatitis B vaccine in future.