为了解甲型肝炎减毒活疫苗的流行病学效果，于1992年始在太仓市22个乡镇的1－3年级小学生和部分幼儿班学生共19375入中进行了该项疫苗的现场效果考核．以个体随机的分组方法将观察对象分为长春苗组、昆明苗组和空白对照组，观察比较注射后72小时内的局部和全身反应，一个月后ALT异常率和历时4年的甲型肝炎发病率．观察结果表明两种疫苗注射后的反应小、安全性好，都具有较好的流行病学效果，长春苗和昆明苗的保护串分别为91．93％、84．01％． In order to understand the epidemiological efficacy of live attenuated hepatitis A vaccine, in situ testing of the vaccines was conducted in a total of 19,375 pupils in grade 1-3 and some kindergarten classes in 22 townships in Taicang City from 1992 onwards. The subjects were randomly divided into Changchun seedlings group, Kunming seedlings group and blank control group. The local and systemic reactions within 72 hours after injection were observed and compared. The abnormality rate of ALT after one month and Hepatitis A Incidence. The results showed that the two vaccines had small reaction and good safety after injection, and all had good epidemiological effects. The protection strings of Changchun and Kunming were 91.93% and 84.01% respectively.