新型冠状病毒核酸血液筛查系统的检测性能评价

Evaluation of SARS-CoV-2 nucleic acid blood screening reagents

目的采用假病毒对三种新型冠状病毒(severe acute respiratory syndrome coronavirus 2,SARS-CoV-2)核酸血液筛查试剂的检测性能进行比较和分析,为SARS-CoV-2核酸血液筛查的试剂选择提供依据。方法使用慢病毒包装系统构建包含SARS-CoV-2基因组片段的假病毒。使用A、B、C三个单位的SARS-CoV-2核酸血液筛查系统进行RNA提取和扩增,根据各试剂检测结果计算其检测限(limit of detection,LoD)、特异度和精密度。结果A、B、C三个单位N区段的单检LoD分别为3.46、8.73、23.87 copies/mL,混检LoD分别为13.65、78.92、159.14 copies/mL。ORF1ab区段的单检LoD分别为6.32、12.22、24.05 copies/mL,混检LoD分别为26.94、67.97、94.80 copies/mL。各试剂检测SARS-CoV-2阴性血浆的特异度均为100%,检测2LoD和较高浓度假病毒的批内和批间变异系数均小于5%。结论A公司的SARS-CoV-2核酸血筛系统灵敏度最高。三种试剂均有良好的特异度和精密度。

Objective To compare and analyze the performance of three nucleic acid blood screening reagents for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)using pseudoviruses,so as to provide references for choosing suitable reagents for SARS-CoV-2 blood screening.Methods PCDH-based pseudovirus containing fragments of SARS-CoV-2 genome was used as reference material.SARS-CoV-2 nucleic acid blood screening reagents from three companies(A,B and C)were used for RNA extraction and amplification.The results were used to calculate limit of detection(LoD),specificity and precision of the reagents.Results For N region,LoDs of company A,B and C were 3.46,8.73 and 23.87 copies/mL for individual testing,and 13.65,78.92 and 159.14 copies/mL for pooling testing respectively.For ORF1ab region,LoD of A,B,C was 6.32,12.22 and 24.05 copies/mL for individual testing,and 26.94,67.97 and 94.80 copies/mL for pooling testing,respectively.The specificity of each reagent in detecting SARS-CoV-2 negative plasma was 100%.The intra-batch and inter-batch coefficient of variation for detecting 2LoD and higher concentration of pseudoviruses were less than 5%.Conclusions The kit of company A had higher sensitivity than those from company B and C.All the kits showed good specificity and precision.