国产甲肝减毒活疫苗(IA-1株)与进口甲肝灭活疫苗的2年免疫效果比较

目的　比较国产甲肝减毒活疫苗和进口甲肝灭活疫苗免疫效果。方法　在广西柳城县筛选出 6～ 1 2岁甲肝易感儿童 2 1 7人 ,以个体随机分为 4个组。B、C组接种国产甲肝减毒活疫苗 (LA - 1株 ,滴度 1 0 6 75 TCID5 0 ) ,接种程序分别为 0 - 6和 0 - 1 2 ;D组接种低滴度国产甲肝减毒活疫苗 (LA - 1株 ,滴度 1 0 6 0 TCID5 0 ) ,E组接种史克公司市售甲肝灭活疫苗 (贺福立适 ,72 0E1 .U) ,接种程序均为 0 - 6。各组于第 1针免后 1 ,6 ,1 2 ,2 4个月 ,第 2针免后 1个月采血 ,用美国ABBOTT公司的ImxmEIA试剂 ,检测甲肝抗体IgG。 结果　滴度 1 0 6 75 TCID5 0 的国产减毒活疫苗两种程序 ,除 0 - 6程序组在第 2针免后 1个月的抗体水平峰值较低外 ,其余各次随访的抗体反应结果均与进口甲肝灭活疫苗相似。低滴度减毒活疫苗 ( 1 0 6 0 TCID5 0 )的抗体阳性率和抗体水平均低于其他各组。结论　滴度 1 0 6 75 TCID5 0 国产甲肝减毒疫苗与进口甲肝灭活疫苗免疫效果相近 ,具有良好的免疫原性和很好的回忆反应 ,加强免疫可以提高疫苗的保护效果和延长保护年限。

Comparison of Two - year Follow - up Immunogenicity Between Live Attenuated Hepatitis A Vaccine and Imported Inacti-vated Vaccine

ObjectiveTo compare immune efficacy of live attenuated hepatitis A vaccine with that of inactivated vaccine.MethodsThese 217 children aged 6-12 years with negative anti-HAV IgG at the enrollment from Liucheng county of Guangxi Zhuang autonomous region were randomized into 4 groups.Groups B and C received the LA-1 strain,a live attenuated HAV vaccine(10 6.75 TCID 50 ,Changchun Institute of Biology Products)according to schedules of 0-6 months and 0-12 months respectively.10 6.0 TCID 50 live attenuated HAV vaccine was administered to group D,and inactivated hepatits A vaccine(Havrix TM ,720E1.U,SKB) to group E both at 0,6 month follow-up bloods were taken at month,6,12,24 after the first dose and 1 month after the second dose for all groups with additional samples at month 1 for Group D and E.All samples were tested for anti-HAV IgG using Imx mEIA kit(Abbott Lab.).ResultsDuring follow-up,in both schedules,live attenuated vaccine had similar effective seroconversion rates and antibody titers as inactivated vaccine at all points of time except for that of the 0-6 months schedule at 1 month after the booster.In group D with lower dose live attenuated vaccine,the anti-HAV positive rate and level were lower than those in the other groups.ConclusionA high dose of attenuated live HAV vaccine with a booster dose was similar to the inactivated vaccine in immunity effect,demonstrating a good immunogenicity and memory.Booster dose will ensure long-term protection against HAV.