摘要目的 报告A+C群脑膜炎球菌多糖疫苗(A+C群MPV)在C群流行性脑脊髓膜炎(流脑)暴发疫情中应急接种的安全性、免疫原性和保护效果.方法 在2002年广西来宾市发生C群流脑局部暴发接种A群MPV人群中约6周后应急接种A+C群MPV,观察接种对象局部和全身反应.选择疫点人群71人和非疫点人群43人于应急接种前和接种后1个月采血,用ELISA检测脑膜炎球菌C群和A群多糖抗体IgG.随访接种人群流脑发病情况至免疫后5年.结果 A+C群MPV应急接种率为97%,接种后未观察到严重不良反应.疫点人群、非疫点人群、应急接种前C群抗体阴性者和阳性者的C群流脑抗体阳性率为97.67%～100%,几何平均浓度(GMC)为30.81～37.44 μg/ml,各组人群抗体水平差异无统计学意义.流脑罹患率在及时接种学校(218.58/10万)比不及时接种学校(705.72/10万)减少69.02%.接种人群随访15 760人年未发现流脑临床确诊病例.结论 国产A+C群MPV应急接种可成功扑灭C群流脑暴发疫情,与A群MPV仅间隔6周接种仍然安全,对易感人群可诱导产生高水平的特异性抗体,对已有抗体者可显著提高抗体水平,保护效果至少持续5年.

abstractsObjective To assess the safety, immunogenicity and efficacy of group A and C meningococcal polysaccharide vaccine (A/C MPV) in response to an outbreak of group C meningococcal disease. Methods A vaccination campaign with A/C MPV was prompted 6 weeks after the use of group A MPV in Laibin city, Guangxi, where an outbreak of group C meningococcal meningitis occurred in 2002.Vaccinees were observed for local and systemic reactions after the vaccination and followed up for the meningococcal disease for 5 years. Blood samples were collected from 71 people in the epidemic and 43 in the non-epidemic areas before and 1 month after the vaccination and examined by ELISA to detect IgG antibodies to group A and C polysaccharides. Results The vaccination coverage was 97%. No significant adverse reactions were observed. The positive rates of group C antibodies after vaccination was between 97.67% and 100% among the populations in the epidemic and non-epidemic areas, as well as among those negative and positive for group C antibodies prior to the vaccination.The geometric mean anti-C concentrations ranged 30.81 μg/ml to 37.44 μg/ml, showing no significant difference between groups. The incidence rate of meningococcal disease in students with timely immunization (218.58/100 000) dropped by 69.02% , when compared to that in those with delayed immunization (705.72/100 000). No clinical cases were identified during the follow-up period of 15 760 person-years. Conclusion The vaccination campaign with the Chinese group A/C MPV seemed successful in controlling the group C meningococcal outbreak.The vaccine was shown to be safe even administered after the group A vaccine only 6 weeks apart. It could induce high levels of antibodies in vulnerable population and significantly increase antibody levels in seropositive individuals, thus providing a protection of at least 5 years.