严重发热伴血小板下降综合征病毒核酸检测检出下限评估

Evaluation of lower limit of detection by nucleic acid testing on severe fever with thrombocytopenia syndrome virus

目的评估蜱虫病病毒(SFTSV)核酸检测体系的检出下限。方法采用第三方(美国CDC)提供的临界浓度梯度稀释血清盘,对不同浓度梯度(10、1、0.1、0.01 pfu/m L)共346份SFTSV病毒血清标本做SFTSV RNA检测(4次/份,合计1 384次检测);统计检出的数目和扩增循环数,通过逻辑回归模型,计算该检测体系的最低检出限。结果所建立的SFTSV RNA检测体系的95%和50%最低检出限浓度(pfu/ml)分别为5.4和0.8。结论系统化评估出了SFTSV RNA体系的最低检出下限,为后续应用于献血者血液筛查提供了技术保障。

Objective To evaluate the lowest limit of detection by NAT on severe fever with thrombocytopenia syndrome virus( SFTSV). Methods A serum dilute panel plate with different concentration gradients was provided by the U. S. Center of Disease Control to detect SFTSV virus in 346 series of different dilute concentrations(10,1,0. 1,0. 01 pfu / m L). A highly sensitive NAT system was applied on the panel(4 repeat testing per dilution,1 384 repeats in total) to perform detection on SFTSV RNA. The numbers of testing and cycle were analyzed and calculated by logic regression model to determine the lowest limit of detection. Results Based on a logistic regression on the probability of a positive result as a function of log10 concentration for the non-zero concentrations,95% of results were expected to be positive at 5. 4 pfu / m L,and 50%were expected to be positive at 0. 8 pfu / m L. Conclusion The outcomes of evaluation on the limit of detection may provide comprehensive stability for the further large-scale NAT screening on SFTSV among blood donors.