规范化甲肝减毒活疫苗(H_2株)现场效果研究

A STUDY ON THE EFFICACY OF STANDARDIZED CHINA-MADE LIVE ATTENUATED HEPATITIS A VACCINE(H_2 STRAIN)

目的观察我国研制的规范化甲肝减毒活疫苗 (H2 株 )的流行病学保护效果。方法 35 15名甲肝易感儿童按出生单双月份随机分组 ,其中接种组 180 4名 ,对照组 16 5 3名。观察接种疫苗后两组甲型肝炎发病率。结果对照组发现甲肝病例 14例 ,发病率 8.47‰ ;疫苗组 1例 ,发病率 0 .5 5‰ ,保护率 93.5 1%,95 %下可信限为6 4.5 6 %。结论国产规范化甲肝减毒活疫苗与国外甲型肝炎灭活疫苗保护效果相似。

ObjectiveTo access the efficacy of China-made live attenuated hepatitis A vaccine (H 2 strain).Methods3 515 HAV susceptibles aged from 1～7 years old were randomized individually into vaccine and control group by birth month. Children in the vaccine group were given one dose of live attenuated hepatitis A vaccine while the children in the control group were given nothing. The attack rate in vaccine and control groups were followed up for 3.5 years after vaccination.ResultsIn the 3.5 years of following up, 14 hepatitis A cases were found in the control group and 1 case in control group. The attack rate in vaccine group and control group was 8.47 ‰ and 0.55 ‰ respectively. The difference of attack rate between the vaccine and control groups were significantly important and the efficacy of the vaccine was 93.51 %(95% lower confidence interval: 64.56 %).ConclusionThe efficacy of live attenuated hepatitis A vaccine (>106.5TCID50/ml) was good and it can be used for mass immunization.