[Follow-up study on efficacy of blocking mother-to-infant transmission of HBV and its influence factors in Jiangsu province, 2010-2015].

Objective: To evaluate the effects of blocking transmission of HBV from mother to infant in Jiangsu, and discuss influencing factors related to development of chronic HBV infection in children of HBsAg positive mother. Methods: HBsAg positive mothers delivered during 2010-2015 in three counties of Jiangsu (Zhangjiagang, Danyang and Taixing) and their neonates were included in the study. The neonates were vaccinated with hepatitis B vaccine (10 μg) and hepatitis B immunoglobin (100 units) within 24 hours after birth. Blood samples were collected from the infants 7 months later, and serum HBsAg, anti-HBs and anti-HBc were detected by Abbott particles chemiluminescence. Results: A total of 2 099 children aged 7-52 months were surveyed, of whom 34 (1.62%) developed chronic HBV infection. Logistic regression analysis showed that mother HBeAg positivity (RR=4.997, 95% CI: 2.408-10.370) was the independent risk factors of mother-to-infant transmission of HBV, while elder delivery age (RR=0.264, 95% CI: 0.101-0.691) was independent protective factors of HBV transmission. Among the other 2 065 uninfected children, 9.7% had anti-HBs level less than 10 mIU/ml, 35.4% between 10 and 100 mIU/ml, and 54.9% higher than 100 mIU/ml. The anti-HBs positive rate was 90.3% and the anti-HBc positive rate was 13.7%. The positive rate and geometric mean titers (GMT) of anti-HBs reached the peaks at 7-12 months after birth, and decreased with the age. Conclusions: The current immunological strategy of Jiangsu has good protective efficacy for the interruption of perinatal transmission of HBV. Mother HBeAg positivity is the major risk factor for perinatal blocking failure. Children with effective immunization still need to be monitored for anti-HBs and revaccinated if necessary.