中国首例输入性中东呼吸综合征病例实验室确诊方法比较

Comparison of laboratory methods used for identification of the first imported case of Middle East Respiratory Syndrome infection in China, 2015

目的 对中国首例疑似输入性中东呼吸综合征冠状病毒感染病例进行实验室确诊,并比较不同核酸检测方法灵敏度。方法 采用针对多个靶标（upE,ORF1a,N2,N3）的四种实时荧光定量PCR检测方法,对2015年5月28日中国首例疑似MERS冠状病毒感染患者样本（全血样本1份,咽拭子3份）进行复核,并对检测结果进行比较分析;同时采用2个中东呼吸综合征冠状病毒检测试剂盒对标本进行了检测。结果 送检3份咽拭子多个靶标复核检测结果皆为阳性,1份全血样本仅N2/N3两个靶标检测结果为阳性。采用2个试剂盒皆可检测到送检咽拭子为阳性。结论 实验室确诊送检样本为MERS冠状病毒感染阳性。基于N2与N3靶标核酸检测有更高灵敏度,更适于MERS冠状病毒感染筛查与临床样本检测。

Objective To confirm the first imported case in China of Middle East respiratory syndrome（MERS） virus infection using various reliable laboratory diagnostic method.Methods One whole blood sample and three pharyngeal swabs were collected from a Korean patient in Guangdong Province,who was suspected as having MERS.Four in-house real-time RT-PCR assays targeting upE/ORF1a/N2/N3 gene of MERS virus were applied to validate the MERS-coronavirus （MERS-CoV） infection.The performance of the four in-house real-time RT-PCR assays was compared.Two kits for MERS-CoV detection were also validated using pharyngeal swab specimens.Results Three pharyngeal swabs from the first imported case of MERS in China were confirmed as positive for MERS-CoV by all the in-house assays,while the whole blood samples were detected as positive only using assays targeting N2/N3 gene.Both kits showed performance similar to that of corresponding in-house real-time RT-PCRassays.Conclusion The first imported case was confirmed as MERS-CoV infection by four in-house real-time RT-PCR assays targeting upE/ORF1a/N2/N3 gene.The assays targeting N2/N3 gene showed higher sensitivity than thosetargeting other genes,and therefore,the assays targeting N2/N3 are better choices for screening of MERS-CoV infection among clinical specimens.