安徽省2011年0～6岁儿童脊髓灰质炎抗体水平分析

Analysis of Polio Antibody Levels among children aged from 0 to 6 years in Anhui in 2011

目的了解安徽省学龄前儿童脊髓灰质炎（脊灰）抗体水平,评估脊灰疫苗免疫策略效果。方法采用系统抽样方法,调查安徽省16个县（市、区）的0～7岁年龄组的1 754名儿童,进行脊灰中和抗体水平检测。结果所有调查对象均有脊灰疫苗免疫史,96.41%的调查对象接种3～5次;调查对象脊灰中和抗体Ⅰ、Ⅱ、Ⅲ型阳性率分别为99.43%、99.20%、98.86%;抗体几何平均滴度（geometric mean titers,GMT）分别为1∶193.40、1∶117.26、1∶85.03;98.29%的调查对象3种型别抗体均为阳性。各型间抗体阳性率和GMT差异均有统计学意义（P〈0.01）;各年龄组的Ⅰ、Ⅱ、Ⅲ型抗体阳性率均〉97%,随年龄增长抗体GMT逐渐下降,差异有统计学意义（P〈0.05）,抗体阳性率差异无统计学意义（P〉0.05）;皖北、皖中、皖南地域脊灰抗体阳性率均〉98%,不同地域阳性率差异无统计学意义（P〉0.05）,抗体GMT差异有统计学意义（除F_Ⅱ之外,P〈0.05）;多元分析发现年龄、地域和3种型别均阳性对抗体GMT的影响差异有统计学意义（P〈0.01）。结论安徽省学龄前儿童脊灰抗体阳性率和几何平均滴度均保持在较高水平,通过脊灰疫苗接种,已建立牢固的脊灰免疫屏障。

Objective To investigate the level of poliomyelitis antibody among preschool age children,and evaluate the effect of polio immunization. Methods Seven age groups among 0 to 7 years children were sampled by the systematic sampling method in 16 counties in Anhui,and 1 754 serum samples were collected. Microplate neutralization test was used to determine antibody level. Results All of subjects had immunization records while 96. 41% of them were 3- 5 times.The rates of neutralized antibodies positive to Ⅰ,Ⅱ and Ⅲ were 99. 43%,99. 20% and 98. 86%,respectively. The geometric mean titers（ GMT） toⅠ,Ⅱ and Ⅲ were 1∶ 193. 40,1∶ 117. 26 and 1∶ 85. 03,respectively. 98. 29% of the subjects were all positive inⅠ,Ⅱ and Ⅲ. Both positive rate and GMT between each serotype had significant differences（ P〈0. 01）. The positive rates of each serotype were above 97% in all age groups. For GMTs,not like positive rates（ P〈0. 05）,a trend of decreasing with increasing age was presented（ P〈0. 05）. The positive rates of different regions as south of Anhui,middle of Anhui,north of Anhui were all above 98% but without significant differences（ P〈0. 05）. Antibody levels between different regions have significant differences（ P〈0. 05,except FⅡ）. The results of multiple-factors analysis showed that the GMTs were significantly associated with age,region and the result of all positive in each serotype（ P〈0. 01）. Conclusion In preschool age childre in Anhui,the positive rate of poliomyelitis antibody and GMTs are still maintaining a high level,and a stable immunization barrier has been established by polio immunization.