Robert Koch Institute, Nordufer 20, 12353 Berlin, Germany.
J Clin Virol. 2011 Nov;52(3):257-60. doi: 10.1016/j.jcv.2011.08.010. Epub 2011 Sep 3.
WNV epidemics occur worldwide, new WNV isolates were isolated in southern-east Europe belonging to WNV lineage 2. A first international proficiency study on WNV indicted that some laboratories were not able to detect WNV lineage 2 virus genome by their PCR diagnostic assays. Therefore an actual External Quality Assessment with both virus lineages was performed to monitor the improvements in molecular diagnostics.
To asses the proficiency of laboratories to detect West Nile virus with molecular diagnostic tests.
A test panel of different WNV isolates and virus dilutions was given to 26 laboratories to test the samples with their routine diagnostic methods.
Twenty-one participating laboratories provided 28 data set results. WNV lineage 1 was detected with high overall efficiency of 92% (67.9-100%) but two different WNV lineage 2 strains were detected at lower rates (mean = 73%, 67.9-75%) by the different PCR assays. 93% of the laboratories were able to detect a WNV lineage 1 with a concentration of 1.2×10(4)copies/ml but the detection rate was decreased to 68% for 1.2×10(3)copies/ml. One laboratory generated false-positive result from the non-virus control samples and 29% of the datasets showed false-positive results for non-WNV flavivirus samples.
The WNV EQA showed an improved proficiency of laboratories as compared to the first EQA. However, the data suggest that problems in the detection of both lineages were still present since the first proficiency test was performed in 2006. Further proceedings versus the detection of both lineages are needed particularly for in-house assays.
西尼罗河病毒（WNV）在全球范围内流行，在东南欧新分离到的 WNV 株属于 WNV 谱系 2。首次国际 WNV 能力验证研究表明，一些实验室无法通过其 PCR 诊断检测到 WNV 谱系 2 病毒基因组。因此，进行了一次实际的包含两个谱系的外部质量评估，以监测分子诊断的改进情况。
评估实验室使用分子诊断检测西尼罗河病毒的能力。
将不同的 WNV 分离株和病毒稀释液的检测面板分发给 26 个实验室，使用其常规诊断方法检测样本。
21 个参与实验室提供了 28 组数据集结果。WNV 谱系 1 的检测总体效率很高，为 92%（67.9%-100%），但不同的 PCR 检测方法对两种不同的 WNV 谱系 2 株的检测率较低（平均值=73%，67.9%-75%）。93%的实验室能够检测到浓度为 1.2×10(4)拷贝/ml 的 WNV 谱系 1，但当浓度降低至 1.2×10(3)拷贝/ml 时，检测率下降至 68%。一个实验室从非病毒对照样本中产生了假阳性结果，29%的数据集对非 WNV 黄病毒样本显示了假阳性结果。
与第一次能力验证相比，WNV 能力验证显示实验室的能力有所提高。然而，数据表明，自 2006 年进行第一次能力验证以来，检测两个谱系仍然存在问题。需要进一步针对两个谱系的检测进行处理，特别是针对内部检测。
