2004-2007年浙江省麻疹疫苗质量及免疫成功率监测结果分析

目的分析2004-2007年浙江省麻疹高发原因。方法对2004-2007年浙江省麻疹疫苗质量及免疫成功率监测结果进行分析。麻疹疫苗质量监测采用定点和线性两种方式,免疫成功率监测通过对比8月龄儿童接种前后麻疹抗体水平的变化进行。结果从浙江省疾病预防控制中心冷库采集的31个批次的麻疹疫苗均合格,效价为（3.16±0.25）logTCID50/0.1ml;从浙江省市、县、乡各级监测点所采集的47份麻疹疫苗均合格,效价为（3.04±0.32）logTCID50/0.1ml,且各级监测点麻疹疫苗效价差异无统计学意义。8月龄接种1剂次麻疹疫苗可使95%的儿童获得保护性抗体,免疫前抗体水平越高免疫后阳转率越低。结论2004-2007年浙江省应用的麻疹疫苗处于保护效价水平,且初免效果良好,尚不能认为是近年麻疹高发的主要原因。需继续开展含麻疹成分疫苗的质量和免疫成功率监测。

Analysis of surveillance results of measles vaccine quality and success rates of immunization in Zhejiang province 2004-2007

Objective To identify the cause of high incidence of measles in Zhejiang from 2004 to 2007. Methods The results of surveillance of measles vaccine quality and the success rate of immunization in Zhejiang province from 2004 to 2007 were analyzed. Fixed-point and linear approaches were employed in the surveillance of measles vaccine quality; and the success rate of immunization was determined by measuring the difference between the measles antibody levels before and after immunization among 8-month-old children. Results Thirty-one batches of measles vaccines collected from the central cold storage of Zhejiang Center for Disease Control and Prevention were qualified, the titer being （3.16 ± 0.25 ） log TCIDs0/0.1 ml; 47 measles vaccines collected from the town- and county-level, municipal and provincial monitoring sites were qualified, the titer being （ 3.04 ± 0.32 ） log TCID50/0.1 ml, and no statistically significant difference was shown among the monitoring points at all levels. Measles vaccination for 8-month-old children would ensure 95% of the children protective antibodies; the higher the pre-immunization antibody levels, the lower seroconversion rate after immunization. Conclusion Measles vaccines applied in Zhejiang province from 2004 to 2007 achieved a protective potency with favorable primary immunization effects. It is thus not considered to be the major cause for high incidence of measles in recent years. Subsequent surveillance of the quality of measles composition-containing vaccines and the success rate of immune is required.