乙肝疫苗免疫儿童表面抗体衰减最小年龄分析

Minimum age of hepatitis B virus surface antibody attenuation in children with basic vaccination of three doses: model fitting analysis

目的 了解儿童完成乙肝疫苗0、1、6月三针基础免疫后表面抗体衰减最小年龄,为制定科学强化免疫策略提供依据。方法 采用酶联免疫吸附（ELISA）法检测新疆2 206名年龄≤7岁常规体检儿童乙肝病毒血清学标志物,通过模型拟合未感染儿童不同年龄段中位年龄或实际年龄与表面抗体阳性率的关系,计算表面抗体衰减的最小年龄。结果 2.72%（60/2 206）的儿童处于乙肝病毒不同感染时期（模型1-14）;28.51%（629/2 206）的儿童乙肝表面抗体阴性（模型15）,可能为乙肝病毒易感者,68.77%（1 517/2 206）的儿童乙肝表面抗体阳性,为乙肝疫苗免疫者（模型16）;2 146名未感染儿童表面抗体阳性率为70.69%（1 517/2 146）,不同性别儿童表面抗体阳性率差异无统计学意义（P〉0.05）,4.0~4.5岁年龄段阳性率最低（49.52%）;使用中位年龄和实际年龄拟合模型得表面抗体衰减的最小年龄分别为3.99周岁和4.01周岁。结论 完成乙肝疫苗免疫后的表面抗体阳性儿童在4岁年龄段有必要进行乙肝血清学标志物检测,及时复种,以保证良好的免疫屏障。

Objective To investigate the minimum age of hepatitis B virus （HBV） surface antibody （HBsAb） attenu- ation among the children with basic hepatitis B vaccination at the age of 0,1, and 6 months and to provide a scientific ba- sis for making immunization strategy. Methods Totally 2 026 children aged ≤ 7 years visiting a healthcare clinic for routine physical examination were recruited from January 2011 through December 2014 and serum markers of HBV infec- tion were detected among the children with enzyme-linked irnmunosorbent assay（ELISA）. Model fitting was adopted to analyze associations of median age and real age with positive rate of HBsAb for the children of different age groups for estimating the minimum age for HBsAb attenuation. Results Of the children,2. 72% （60）had HBV infection of differ- ent period as described by 14 expressions of model 1 to model 14 ;28. 51% （629）were negative for HBsAb and suscepti- ble to HBV infection（ model 15 ） ;68. 77% （1 517 ）were positive for HBsAb and unsusceptible to HBV infection（ model 16）. Among the 2 146 children without HBV infection,the positive rate of HBsAb was 70. 69% and no significant be- tween-gender difference in the rate was observed （P 〉 0. 05 ）. The lowest HBsAb positive rate （49. 52% ） was observed among the children aged 4. 0 -4. 5 years. The estimated minimum median age and actual age for HBsAb attenuation were 3.99 and 4.01 years,respectively, based on the results of model fitting. Conclusion The study results suggest that sero- logical markers of HBV should be tested at the age of 4 years among the children with basic vaccination of three doses for the implementation of supplementary HBV vaccination.