A、C群脑膜炎球菌-b型流感嗜血杆菌多糖结合疫苗免疫学效果观察

目的观察A、C群脑膜炎球菌-b型流感嗜血杆菌(Meningococcal group A&C/Haemophilus influenzae type b,ACHib)多糖结合疫苗的免疫原性。方法采用开放、完全随机、盲态观察的方法,将1 800名观察对象分为临床试验组和对照组,每组各900名,两组又按3个年龄段分为3～5、6～11和12～71月龄组。试验组仅经上臂三角肌肌内注射试验疫苗(ACHib多糖结合疫苗),对照组分别经左右上臂同时注射两种对照疫苗(A、C群脑膜炎球菌多糖结合疫苗和Hib结合疫苗)。3～5月龄组免疫3针,每针间隔1个月;6～11月龄组免疫2针,每针间隔1个月;12～71月龄组免疫1针。分别于免疫前、全程免疫后30～35 d采集静脉血,分离血清,采用功能性抗体杀菌力法检测A、C群脑膜炎球菌血清杀菌抗体滴度,间接ELISA法检测Hib抗体水平,并计算抗体阳转率及抗体增长倍数。结果免疫后,3个年龄段的试验组与对照组血清A、C群脑膜炎球抗体和Hib抗体阳转率差异均无统计学意义(P>0.05)。3个年龄段试验组与对照组易感和非易感人群A、C群脑膜炎球菌抗体滴度差异均无统计学意义(P均>0.05),而试验组Hib抗体水平低于对照组,且差异有统计学意义(P<0.001)。结论 ACHib多糖结合疫苗具有良好的免疫原性,可作为上述3种病原菌的预防制剂推广使用。

Immune effect of a meningococcal groups A&C/Haemophilus influenzae type b conjugate vaccine

Objective To observe the immune effect of meningococcal groups A&C / Haemophilus influenzae type b conjugate vaccine(ACHib).Methods An open,random and blind trial was performed.A total of 1 800 children were divided into trial and control groups,900 for each,which were further divided into three subgroups according to the age(3 ～ 5,6 ～ 11 and 12 ～ 71 months).The children in trial group were injected i.m.with ACHib vaccine in deltoid of upper arm,while those in control group with two control vaccines,i.e.meningococcal group A & C conjugate vaccine and Haemophilus influenzae type b conjugate,in left and right arms respectively.The children at ages of 3 ～ 5 months were injected with 3 doses at an interval of 1 month,while those at ages of 6 ～ 11 months with 2 doses at an interval of 1 month,and those at ages of 12 ～ 71 months with one dose.Venous blood samples were collected before and 30 ～ 35 d after immunization respectively,from which sera were isolated and determined for bactericidal antibody titer against meningococci groups A&C by functional antibody bactericidal test,and for antibody level against Hib by indirect ELISA,based on which the positive conversion rate and increasing folds of antibodies were calculated.Results The positive conversion rates of antibodies against meningococci groups A&C and Hib in sera of children at various ages in trial group showed no significant difference with those in control group(P > 0.05).No significant differences were observed in antibody titers against meningococci groups A&C in susceptible and non-susceptible children at various ages in trial and control groups(each P > 0.05).However,the antibody levels against Hib were significantly lower in trial group than in control group(P < 0.001).Conclusion ACHib showed good immunogenicity,which was worthy of popularization as a prophylactic product against meningococci groups A&C and Haemophilus influenzae type b.