[Study on the non-and-low response and its determinants to recombinant yeast-derived hepatitis B vaccines among neonates after primary immunization in Shanghai].

Objective: To evaluate the non-and-low response to primary immunization of recombinant yeast-derived hepatitis B vaccines (YDVs) among neonates and to probe its determinants, in Shanghai.

Methods: Two thousand and forty-seven infants, born during 2008 - 2009 in three districts of Shanghai and administered with 3 dosages of YDVs according to 0 - 1 - 6 month schedule, were selected as subjects. Anti-HBs titers were evaluated by Chemiluminescence Microparticle Immuno Assay and related information was collected from parents through questionnaires. Univariate analysis and logistic regression model were used to probe the determinants among those infants with non-and-low response.

Results: The max-titer of anti-HBs in 2047 subjects was 14 982.7 mIU/ml, whereas the min-titer was 0.52 mIU/ml. The GMC was 408.04 mIU/ml after primary immunization of YDVs. The proportion of infants with titers of < 100 mIU/ml (non-and-low response) was 17%, in which the proportion with titers of < 10 mIU/ml (non response) was 1.86% and the proportion with titers of 10 - 99 mIU/ml (low response) was 15.14%. Data from both univariate analysis and Ordinal logistic regression suggested that gender, age, premature labor, type of vaccines, double positive for both HBsAg and HBeAg were determinants of non-and-low response for infants, with the OR value of 1.365 for male infants, 3.133 for infants with 13 - 18 months old, 2.824 for premature infants, 4.540 for infants administered by 5 µg YDVs and 2.298 for infants whose mother was double positive for both HBsAg and HBeAg.

Conclusion: Male infants, infants with 13 - 18 months old, premature infants, infants administered by 5 µg YDVs and infants whose mother were double positive for both HBsAg and HBeAg had comparatively worse response for YDVs, suggesting that the anti-HBs titer surveillance programs set for these infants should be strengthened.