乙型脑炎减毒活疫苗安全性和免疫原性观察

目的 观察乙型脑炎（乙脑）减毒活疫苗的接种反应和免疫原性.方法 分别选择52名（8月龄～50岁）和607名（8月龄～12岁）健康志愿者进行Ⅰ和Ⅲ期临床试验.试验组每人接种1次由上海生物制品研究所有限责任公司研制的乙脑减毒活疫苗（0.5 ml）,对照组接种同样剂量的已上市乙脑减毒活疫苗.两组接种后的不良反应率和中和抗体阳转率用x2检验进行比较,中和抗体几何平均滴度用t检验进行比较.结果 试验组接种后有5.91％的人体温升高,对照组为7.96％,两组的体温反应发生率差异无统计学意义（x^2 =0.917,P=0.338）.试验组Ⅰ期试验局部反应率为1.92％,Ⅲ期试验为0.25％,对照组Ⅲ期试验局部反应率为0.50％,两组的局部反应率差异无统计学意义（确切概率法,P=0.553）.Ⅲ期免疫原性试验中,试验组的血清中和抗体阳转率为89.00％,抗体几何平均滴度为29.69;而对照组分别为74.59％和19.25,差异均有统计学意义（x^2=11.708,P=0.001;t=4.281,P=0.001）.结论 本研究的试验性乙脑减毒活疫苗接种反应轻微,并具有良好的免疫原性.

Safety and immunogenicity of an attenuated Japanese encephalitis live vaccine

Objective To observe adverse reaction and immunogenicity of an attenuated Japanese encephalitis live vaccine for human use.Methods Phases Ⅰ and Ⅲ clinical trials were performed in 52 healthy volunteers aged between 8 months and 50 years and 607 children aged between 8 months and 12 years,respectively.Subjects were inoculated with 1 dose （0.5 ml） of the test vaccine.A licensed vaccine was used as control.The rates of adverse reaction and seroconversion between the test and control groups were compared with chi-square test.Geometric mean titer （GMT） of neutralizing antibody was compared with t-test between the two groups.Results The rates of rise in temperature were 5.91% and 7.96% in the test group and control group,respectively.There was no statistical difference between the two groups （x^2=0.917,P=0.338）.The rates of local reaction in test group were 1.92% and 0.25%in Phases Ⅰ and Ⅲ,respectively,compared with 0.50% in control group in Phase Ⅲ.No significant difference was found between the two groups （exact probability,P=0.553）.The seroconversion rates and GMT of neutralizing antibody in test group were 89.00% and 29.69,compared with 74.59% and 19.25 in control group （x^2 =11.708,P=0.001; t=4.281,P=0.001）.Conclusion The test vaccine is proved to be safe and immunogenic.