【摘要】 目的探讨国产规范化甲肝减毒活疫苗 (LA -1株 )大规模免疫后的长期保护效果。方法将广西7个县(市)1.5～10岁儿童212985人随机分成疫苗接种组 (100735人 )和对照组 (112250人 )。疫苗组接种1针国产甲肝减毒活疫苗 (LA -1株 ,滴度106.75 TCID50)。免后1个月开始对两组观察肝炎发病情况。结果随访3年 ,对照组发现甲型肝炎病人71例 ,发病率63.25/10万 ;疫苗组发现2例 ,发病率1.99/10万 ,保护率96.85 % ,95 %可信度下限为92.44 %。结论规范化甲肝减毒活疫苗(LA -1株 )可产生满意而较为持久的保护效果。更多还原

【Abstract】 Objective To evaluate the long_term protective efficacy of large scale immunization with a standardized live attenuated hepatitis A vaccine （LA₁ strain）.Methods A randomized controlled double blind study was conducted in 212 985 children between 1.5 and 10 years of age from 7 counties in Guangxi Province （100 735 in vaccine group and 112 250 in control group）.Vaccine group was received one dose of HAV vaccine of 106.75 TCID50. Surveillance of the incidence of hepatitis A in two groups was started 1 month after vaccination. Results During a follow up of 36 months,71 cases of symptomatic HAV infection were found in the control and 2 in the vaccine group（63.25/106 vs. 1.99/106 respectively）. The protective efficacy was estimated at 96.85% with 95% lower confidence limit of 92.4%. Conclusion It shows that a single standardized dose of live attenuated hepatitis A vaccine can come into being high and persistent protection against HAV.更多还原