【摘要】 目的　观察甲型肝炎 (甲肝 )减毒活疫苗H2 株与LA 1株的不同剂量、不同免疫程序的免疫原性及抗体动态变化。方法　在河北、广西两地选择 318名经甲肝抗体检测为阴性的易感儿童 ,按不同剂量程序及不同甲肝疫苗 ,分为 6组 ,并在首剂接种后 1、6、7、12、13月份分别采集血清标本 ,检测甲肝总抗体。结果　各组抗体水平均于再免疫后 1个月达高峰 ,以后开始下降 ;再免半年后抗体水平仍明显高于初免抗体水平 ;灭活疫苗与不同剂量的减毒活疫苗再免后抗体阳转率均达 10 0 % ,并于再免半年后仍维持在 10 0 %。结论　甲肝减毒活疫苗加强免疫能诱导很好的免疫记忆反应 ,其免疫学效果与史克灭活疫苗相当 ;加强免疫的针次宜有一定时间间隔 ,在抗体水平较高时 ,加强免疫意义不大 ;加强免疫应能提高免疫持久性更多还原

【Abstract】 Objective To study the immunology effects of live attenuated hepatitis A vaccine in different doses and schedules groups, and compare with inactivated hepatitis A vaccine(Havrix, Smithkline). Methods 318 susceptible children were enrolled in Guangxi and Hebei province. These subjects were divided into six groups. Each group was vaccinated with either inactivated vaccine or different doses and schedules of live attenuated vaccine. Serum specimens were collected and tested for anti HAV antibody at different time after the vaccination. Results GMT of each group arrived at the peak 1 months after re vaccination, then declined, and GMT of 6 months after booster dose was still significantly higher than that after primary immunization. Sero conversion rates in all groups reached 100% after a booster dose, and kept at 6 months after booster dose. Conclusions A booster dose of live attenuated vaccine can induce secondary immune response well. The immunology effects after booster dose are comparable with inactivated vaccine and it should be useful to the immune persistence.更多还原