福建省脊髓灰质炎疫苗转换前后脊髓灰质炎抗体水平监测

Poliomyelitis antibody levels before and after the polio vaccine switch in Fujian province

目的评价福建省2016年脊髓灰质炎(脊灰)疫苗转换前全人群和转换前后目标儿童脊灰抗体水平。方法采用分层随机抽样方法,在疫苗转换前抽取0-82岁人群且在疫苗转换18个月后抽取<5岁儿童,采集血标本,检测脊灰中和抗体,比较转换前后儿童抗体阳性率和几何平均滴度(GMT)。结果疫苗转换前0-82岁人群脊灰病毒Ⅰ、Ⅱ、Ⅲ型抗体阳性率分别为96.29%、95.53%、92.21%,GMT(1:)分别为78.59、55.83、32.89。脊灰疫苗转换前后<3岁儿童脊灰病毒Ⅰ型、Ⅲ型抗体阳性率分别为99.19%vs 99.11%(x2=0.006,P=0.94)、97.52%vs98.20%(x2=0.16,P=0.69),GMT(1:)分别为215.57 vs 325.88(t=-2.37, P=0.018)、128.74 vs 199.42(t=-2.30,P=0.02)。脊灰疫苗转换前后3-4岁儿童脊灰Ⅰ型、Ⅲ型抗体阳性率分别为98.73%vs 98.86%(x2=0.008,P=0.93)、95.60%vs97.70%(x2=0.71,P=0.40),GMT(1:)分别为171.74vs 155.86(t=0.51,P=0.61)、53.29vs 72.70(t=-1.46,P=0.15)。结论脊灰疫苗转换前福建省全人群已建立良好的脊灰免疫屏障,疫苗转换后未影响目标儿童脊灰抗体水平。

Objective To evaluate antibody levels against poliomyelitis in the entire population and to compare antibody levels of vaccine-target-age children before and after the 2016 polio vaccine switch in Fujian province. Methods We used a stratified sampling technique to enroll 0-82 year olds before the switch, and children who were <5 years old 18 months after the switch. We collected blood samples to test for polio neutralizing antibody. We compared the before and after vaccine-target-age groups on antibody positivity and geometric mean titer(GMT). Results Positivity rates of antibody against poliovirus(PV) type Ⅰ, Ⅱ, and Ⅲ among 0-82 year olds before the switch were 96.29%, 95.53%, and92.21%, with GMTs(1:) of 78.59, 55.83, and 32.89, respectively. Among <3 year old children, positivity rates of PVⅠand PVⅢ antibody before vs after the switch were 99.19% vs 99.11%(x2=0.006, P=0.94) and 97.52% vs 98.20%(x2=0.16,P=0.69), with GMTs(1:) of 215.57 vs 325.88(t=-2.37, P=0.018) and 128.74 vs 199.42(t=-2.30, P=0.02), respectively.Among 3-4 year old children, positivity rates of PV Ⅰ and PV Ⅲ antibody before vs after the switch were 98.73%vs 98.86%(x2=0.008, P=0.93) and 95.60% vs 97.70%(x2=0.71, P=0.40), with GMTs(1:) of 171.74 vs 155.86(t=0.51,P=0.61) and 53.29 vs 72.70(t=-1.46, P=0.15), respectively. Conclusions A high population-wide immune barrier had been established before the polio vaccine switch;the switch did not affect polio antibody levels of vaccine-target-age children.