“八五”期间，对国产Ｈ２株甲肝减毒活疫苗进行了大规模现场考核，由于现场所用疫苗滴度偏低（约为１０５.０～５.５ＴＣＩＤ５０），免疫后抗体阳性率仅为３０％－４０％，保护效果约为７０％，结果不甚理想。为此我们对滴度在 １０６.５ＴＣＩＤ５０以上的疫苗（规范化）再 During the “Eighth Five-Year Plan” period, a large-scale on-site examination was conducted on live-attenuated live attenuated hepatitis A virus vaccine produced in China. Due to the low titers (about 105.0 ~ 5.5 TCID50) used on site, the positive rate of antibody after immunization was only 30 % -40%, the protective effect is about 70%, the result is not very satisfactory. To this end we have a titer of more than 106.5TCID50 vaccine (standardized) and then