【摘要】 183,609名儿童服中I₉株活疫苗未见不良反应及与疫苗有关的病例。283名服苗者中和抗体四倍增长率为82％,显著高于LSc,2ab株,阳转率为84.6％。抗体几何平均滴度服苗后较服苗前增长25.9倍。318名服苗儿童总排毒率为73.3％,易感儿童则85.4％,亦显著高于LSc,2ab株。中I₉株经人肠道传代后的子代病毒部分有返祖现象,与平行对照LSc,2ab株基本相似。更多还原

【Abstract】 The results of investigation of 3 field trials with Zhong I₉ strain of type I live poliovaccine were reported. In a total of 183, 609 children fed with Zhong I₉ strain vaccine, no side effect or vaccine associated reaction was noticed, even in those having close contact with them. The conversion rate of neutralizing antibody of 283 children tested was 84.6% and the 4 fold antibody rise rate was 82%. The isolation rate of homotypic virus was 73.3%. The geuetic stabi- lity of sabin LSc, 2ab and I₉ strains after passing through human alimentary tracts was comparatively studied and showed the same T, d characters and the neurovirulence test of both strains showed a slightly elevated virulence without significant difference.更多还原