肠道病毒EV71和CAV6分离效果影响因素分析

Analysis of influence factors of Ctvalue and inoculation dose on enteric virus EV71 and CAV6 isolation efficiency

目的探讨肠道病毒EV71、CAV6样本荧光定量RT-PCR的Ct值、接种剂量等因素对病毒分离效果的影响。方法采集确诊手足口病例咽拭子、肛拭子标本,应用荧光定量RT-PCR法检测病毒核酸,选取强阳性、阳性、弱阳性EV71、CAV6标本各30份,按不同剂量梯度(100,200,300,400μL)接种于RD细胞进行病毒培养分离。结果 180份标本的总体分离阳性率为52.2%,其中EV71阳性率60.0%,CAV6阳性率44.4%,差异有统计学意义(P<0.05);肛拭子分离阳性率60.9%,咽拭子分离阳性率43.2%,差异有统计学意义(P<0.05)。不同接种剂量的病毒分离阳性率差异有统计学意义(P<0.05)。结论肠道病毒EV71、CAV6标本荧光定量RT-PCR的Ct值、接种剂量、标本类型、分离细胞株对分离阳性率均有影响。

Objective To study influence factors such as C, value of real time RT-PCR and inoculation dose on enteric virus EV71 and CAV6 isolation efficiency. Methods Throat swab and anal swab specimens of confirmed HFMD patients were col- lected, real-time RT-PCR was used for nucleic acid analysis, among which 30 positive specimens of EV71 ,CAV6 with different C, values（strongly positive, positive , weakly positive） were selected, respectively, which were inoculated to RD cells with dif- ferent doses（100,200,300,400 μL） for virus isolation. Results For 180 specimens, the isolation positive rate was 52.2%. The isolation positive rate of EV71 specimens（60.0 % ） was higher than that of CAV6（44.4 % ）, with statistical difference（P〈0.05）. The isolation rate of anal swab specimens（60.9 %） was higher than that of throat swab specimens（43.2 % ）, with statis- tical difference（P〈0.05）. Statistical difference was observed among isolation positive rates of different inoculation doses（P〈 0.05）. Conclusion The C, value, inoculation dose, specimen type of enteric virus EV71 and CAV6 together with cell line were influenee factors for virus isolation efficiency.