甲型肝炎减毒活疫苗再免疫的研究

目的 对甲型肝炎减毒活疫苗加强免疫的可能性进行研究。方法 分别设置再免疫组、初免疫组和自然感染组。用Ａｂｂｏｔｔ ＥＩＡ改良法定性和定量检测血清中的甲型肝炎抗体。结果 再免疫后甲型肝炎抗体阳性率和几何平均滴度在２周内升高，与初免疫组抗体阳性率和几何平均滴度缓慢上升至３个月以后达到高峰形成对比。再免疫组和自然感染组对活性疫苗免疫反应存在区别，这在研究疫苗免疫持久性时应予考虑。再免疫组初免功能抗体又转

Studies on Re immunization with Live Attenuated Hepatitis A Vaccine

OBJECTIVE: The possibility of re-immunization with a booster dose of live attenuated hepatitis A (HA) vaccine was studied. METHODS: Children randomly sampled were divided into three groups with re-immunization, primary immunization and immunity via natural infection. Antibodies against hepatitis A virus (anti-HAV) were detected qualitatively and quantitatively with modified Abbott enzyme immunoassay (EIA). RESULTS: Proportion of children with positive anti-HAV and its mean geometric titer (GMT) increased within two weeks after re-immunization, and as compared, those increased slowly and GMT reached the peak three months after primary immunization. Response to the live attenuated vaccine differed between the groups of re-immunization and immunity via natural infection, and should be taken into consideration in studying immune persistence of the vaccine. Proportion of children, who converted negative of their anti-HAV after primary immunization, with positive anti-HAV after re-immunization was 83.3% (10/12), significantly higher than that in those who failed in primary immunization and then were vaccinated again (50%, with 17/34), and that in both of them were higher than in primary immunization (29.6%). CONCLUSION: Reminiscence could be induced by re-immunization, and the effects of it depended on primary immunization. Detection of anti-HAV with modified Abbott EIA still underestimated primary immune reaction. A more sensitive and specific method for detecting anti-HAV after vaccination should be used.