深圳市社区人群EV71和CoxA16隐性感染的流行病学分析

Subclinical infection of hand-foot-mouth disease in Shenzhen City

目的为了解肠道病毒71型(EV71)和柯萨奇病毒A16型(CoxA16)在深圳市健康人群中的隐性感染情况,进一步探讨隐性感染在儿童手足口病(HFMD)中的传播特征及危害性。方法实验采用酶联免疫(ELISA)法检测不同年龄层(0～59岁之间)的健康人群血清中抗肠道病毒71型(EV71)和柯萨奇病毒A16型(CoxA16)的IgM和IgG抗体水平,并采用荧光定量PCR检测IgM阳性的样本中病毒核酸的阳性率。结果抗EV71和CoxA16 IgG抗体的阳性率都随着年龄段的增长呈下降趋势,0～5岁儿童组的IgG抗体阳性率最高,其中抗EV71的IgG抗体阳性率为79.7%,抗CoxA16的IgG抗体阳性率为91.93%。30岁以下者,两种病毒的抗体阳性率在70%以上,显著高于30岁以上人群,P<0.01。5岁以下儿童抗EV71抗IgM抗体阳性率达15.9%。49份抗EV71 IgM阳性样本中有42份EV71的核酸阳性,阳性率为85.7%;31份抗CoxA16 IgM阳性样本中有25份CoxA16核酸阳性样本,阳性率为80.6%。结论人群对EV71和CoxA16普遍容易感染,健康人群中存在较高的隐性感染,隐性感染率与人群的年龄分布存在相关性,因此隐性感染人群也是病原体传播的传染源之一。

Objective To investigate subclinical infection of enterovirus 71（EV71） and Coxsackievirus A16（CoxA16） in health population in Shenzhen and analyze the prevalent features and harmfulness of hand-foot-mouth disease（HFMD）.Methods ELISA was used to detect the antibody against enterovirus71（EV71）,Coxsackievirus A16（CoxA16） in healthy person aged from 0～59 years.Results The positive rate of IgG antibody against EV71 and CoxA16 decreased with the age growth,and the higest positive rate were in 0～5 year old group in which the IgG antibody against EV71 was 79.7% and the IgG antibody against CoxA16 was 91.93%.The positive rates of antibody to both viruses were above 70% in the adult below the age of 30 years,showing significant difference compared with that above age of 30 years（P0.01）.The higest positive rate were in 0～5 year old group with IgM antibody against EV71 was 15.9%.Through real-time RT-PCR,42 out of 49 samples the IgM positive sera positive against IgM antibody were also positive for nucleic acid of EV71 with positive rate of 85.7% and 25 out of 31 positive sera positive against CoxA16 were also positive for nucleic acid of CoxA16 with the positive rate of 80.6%.Conclusion People are generally susceptible to EV71 and CoxA16 and there were subclinical infection with HFMD in healthy population.Subclinical infection of HFMD play very important role in transmition of HFMD.