A群C群脑膜炎球菌结合疫苗的免疫效果

Immune effect of groups A and C meningococcal conjugate vaccine

目的 观察A群C群脑膜炎球菌结合疫苗对6～23月龄、24～35月龄婴幼儿的免疫原性和免疫持久性。方法 选择广西壮族自治区崇左市400名婴幼儿,其中6～23月龄和24～35月龄两个年龄段各200名,分别接种A群C群脑膜炎球菌结合疫苗2剂和1剂。分别于免疫前、全程免疫后1个月、1年采血,血清体外杀菌试验（serum bactericidal assay,SBA）检测血清抗体水平,评价其免疫原性和免疫持久性。结果 免后1个月和1年,两个年龄组婴幼儿A群、C群抗体阳性率和GMT均较免疫前显著提高（P均＆lt;0.001）;免后1年,两个年龄组婴幼儿A群、C群抗体GMT低于免后1个月,但仍高于免前;免后1个月和1年,24～35月龄组婴幼儿A群、C群抗体GMT和增长倍数均但,仍高于免前高于6～23月龄组;两个年龄组龄婴幼儿易感者和非易感者A群、C群抗体阳性率和GMT均显著提高。结论A群C群脑膜炎球菌结合疫苗对6～35月龄婴幼儿具有良好的免疫原性和免疫持久性。

Objective To observe the immunogenicity and immunopersistence of groups A and C meningococcal conjugate vaccine in infants at ages of 6 - 23 and 24 - 35 months. Methods A total of 400 infants,200 at ages of 6 -23 months and 200 at 24 - 35 months,were immunized with 2 and 1 dose of groups A and C meningococcal conjugate vaccine respectively. Blood samples were collected before immunization and one month and one year after the last immunization,and determined for serum antibody level by serum bactericidal assay（SBA） in vitro to evaluate the immunogenicity and immunopersistence of vaccine. Results Both the antibody positive rates and GMTs against groups A and C meningococci of infants in two age groups one month and one year after immunization increased significantly as compared with those before immunization（each P 〈 0. 001）. However,the GMTs in two groups one year were lower than those one month after immunization,while were still higher than those before immunization. Both GMTs and their increasing folds in the infants at ages of 24 - 35 months one month and one year after immunization were significantly higher than those at 6 - 23 months（each P 〈 0. 001）. Both the antibody positive rates and GMTs against groups A and C meningococci of susceptible and insusceptible infants in two age groups increased significantly. Conclusion Groups A and C meningococcal conjugate vaccine showed good immunogenicity and immunopersistence in infants at ages of 6 - 35 months.