摘要目的 评价甲型肝炎(甲肝)灭活疫苗在成年人中加强免疫的效果和安全性.方法 选择参加健康成年人甲肝火活疫苗和冻于甲肝减毒活疫苗随机双盲临床试验,基础免疫前甲肝抗体阴性并完成1针甲肝灭活疫苗或减毒活疫苗的大学生作为研究对象,加强免疫1针甲肝灭活疫苗,免疫前、免疫后28 d采血,检测抗甲肝病毒抗体滴度≥20mIU/ml为阳性.结果 加强免疫前甲肝灭活疫苗组和减毒活疫苗组GMC分别为70.80mIU/ml、50.12 mIU/ml;阳性率分别为94.7％、65.0％.加强免疫1针甲肝灭活疫苗后,两组的抗体阳性率均为100.0％,灭活疫苗组和减毒活疫苗组GMC分别为2 816.09mIU/ml、2 654.55mIU/ml.结论 接种1针甲肝灭活疫苗或减毒活疫苗3年后,甲肝抗体GMC和阳性率均有不同程度降低,灭活疫苗优于减毒活疫苗,两组进行1针灭活疫苗的加强免疫效果明显.

abstractsObjective To evaluate the safety and immunogenicity of one booster dose of inactivated hepatitis A vaccine in young adults.Methods The subjects were selected from participants in the clinical trial of immunogenicity of inactivated and attenuated live hepatitis A vaccine in young adults.Eligible subjects were those who had received one dose of inactivated or attenuated hepatitis A vaccine,could be contacted and were sero-negative before primary vaccination.All qualified subjects were immunized with one booster dose of inactivated hepatitis A vaccine.The blood samples were collected before booster dose vaccination and 28 days after the immunization.Anti-HAV antibody titer ≥20 mIU/ml was considered to be sero-protected against hepatitis A virus.Results The GMCs in the inactivated HAV vaccine group and attenuated live vaccine group before booster dose vaccination were 70.80 mIU/ml and 50.12 mIU/ml,respectively,and the sero-protection rates were 94.7％ and 65.0％,respectively.After the vaccination of the booster dose,the sero-protection rates in both groups were 100.0％,and the GMCs were 2 816.09 mIU/ml and 2 654.55 mIU/ml,respectively.Conclusion The GMCs and sero-protection rates of anti-HAV antibody in young adults declined after three years of the primary vaccination.However,the higher GMC and sero-protection rate were observed in the inactivated vaccine group than in the attenuated live vaccine group.Significant increases of GMC levels were observed in both groups after one booster dose vaccination.