湖南和甘肃省2014年新生儿脐带血麻疹抗体水平调查

Seroprevalence of Measles in Hunan and Gansu Provinces in China,2014: An Umbilical Cord Blood Survey

目的通过对我国部分地区新生儿脐带血麻疹免疫球蛋白(Immunoglobulin,Ig)G抗体阳性率和抗体浓度的检测,为制定含麻疹成分疫苗(Measles-containing Vaccine,MCV)免疫相关策略提供参考。方法采用商品化酶联免疫吸附试验检测试剂盒对2014年湖南和甘肃省1044份新生儿脐带血麻疹Ig G抗体进行了检测和定量分析。结果新生儿脐带血麻疹Ig G抗体总阳性率为90.13%,平均抗体浓度为762.5毫国际单位/毫升(m IU/ml);湖南和甘肃省新生儿脐带血麻疹Ig G抗体阳性率和平均抗体浓度分别90.00%,747m IU/ml和90.26%,777m IU/ml,差异无统计学意义(χ2=0.72,P>0.05)。具有完全保护能力的高滴度(≥1000m IU/ml)麻疹Ig G抗体个体占43.01%。随产妇年龄增加,新生儿脐带血麻疹抗体浓度呈显著下降趋势(Spearman秩相关系数=-0.943,P<0.05)。乡村新生儿脐带血麻疹Ig G抗体阳性率和高浓度抗体比例均显著高于城镇新生儿(χ2=10.77,χ2=32.3;P均<0.05)。结论麻疹病例中<1岁婴儿构成比增加可能与出生后无麻疹抗体、抗体衰减较快和产妇生育年龄后移导致母传麻疹抗体滴度降低等因素有关,而≥15岁成人病例增加可能是由于MCV免疫后抗体水平衰减较快导致易感人群累积。应常规开展健康人群麻疹抗体水平监测,提高8月龄首剂MCV接种的及时性,适时对高危成年人群开展MCV补充免疫活动。

Objective To determine the measles immunoglobulin body concentrations of cord blood in various parts of China, and sles-containing vaccine （MCV） immunization strategy. Methods samples were collected in Hunan and Gansu provinces in 2014. （Ig） G antibody positive rate and anti- to provide evidence for improving mea- A total of 1044 umbilical cord blood Measles IgG antibody was detected by ELISA testing. Results The seroprevalence of measles IgG antibody in umbilical cord blood was 90. 13%,with an average antibody concentration of 762.5mlU/ml. The positive rate and geometric mean concentration of measles IgG antibody in Hu- nan and Gansu provinces was 90. 00%, 747mlU/ ml, and 90. 26%, 777mlU/ml, respectively. No significant differences were found （X2 = 0. 72, P 〉 0. 05 ）. The samples with protective titers of measles IgG antibody （ ≥1000mlU / ml） accounted for only 43. 01% of all samples. With increasing maternal age, cord blood measles antibody titers showed a significant downward trend （ Spearman = - 0. 943, P 〈0. 05）. There were significant difference in the positive rates （X2 =32. 3 ,P 〈0. 05） and the levels of mea- sles IgG antibody（x2 = 10. 77 ,P 〈0. 05） between rural and urban areas. Conclusions The increasing number of under 1 year old measles cases was primarily caused by declining measles antibodies after birth, rapid anti- body attenuation, advanced age at reproduction, and other factors leading to decreasing measles antibody ti- ters. The increasing case numbers among adults （age I〉15 years） was mainly due to decreasing antibody level among adults vaccinated as children, leading to accumulation of susceptibles. We should conduct periodic measles antibody seroprevalence surveys among healthy individuals, improve timely vaccination rate for the first dose among 8 month old children, and conduct measles supplementary immunization activities （SIAs） for high risk adult groups at appropriate times.