Bundeswehr Institute for Microbiology, Munich, Germany.
J Appl Microbiol. 2021 Apr;130(4):1173-1180. doi: 10.1111/jam.14863. Epub 2020 Oct 2.
Rapid detection of biological agents in biodefense is critical for operational, tactical and strategic levels as well as for medical countermeasures. Yersinia pestis, Francisella tularensis, and Bacillus anthracis are high priority agents of biological warfare or bioterrorism and many response forces use lateral flow assays (LFAs) for their detection. Several companies produce these assays, which offer results in short time and are easy to use. Despite their importance, only few publications on the limits of detection (LOD) for LFAs are available. Most of these studies used inactivated bacteria or risk group-2 strains. As the inactivation process in previous studies might have affected the tests' performances, it was our aim in this study to determine and compare the LOD of several commercially available LFAs using viable risk group-3 strains.
Lateral flow assays from four different companies for the detection of following bacteria were evaluated: Y. pestis, F. tularensis and B. anthracis spores. Two independent quantification methods for each target organism were applied, in order to ensure high quantification accuracy. LODs varied greatly between tests and organisms and ranged between 10 for Y. pestis-tests and as high as >10 for one B. anthracis-test.
This work precisely determined the LODs of LFAs from four commercial suppliers. The herein determined LODs differed from results of previous studies. This illustrates the need for using accurately quantified viable risk group 3-strains for determining such LODs.
Our work bridges an important knowledge gap with regard to LFA LOD. The LODs determined in this study will facilitate better assessment of LFA-results. They illustrate that a negative LFA result is not suited to exclude the presence of the respective agent in the analyzed sample.
在作战、战术和战略层面以及医疗对策方面，快速检测生物制剂对于生物防御至关重要。鼠疫耶尔森菌、土拉弗朗西斯菌和炭疽芽孢杆菌是生物战剂或生物恐怖主义的高优先级制剂，许多应对部队使用侧向流动检测（LFA）进行检测。几家公司生产这些检测试剂盒，它们提供快速的检测结果，且易于使用。尽管这些检测试剂盒非常重要，但关于 LFA 检测限（LOD）的出版物却很少。这些研究大多使用失活细菌或风险组 2 株。由于先前研究中的失活过程可能会影响检测的性能，因此我们在这项研究中旨在使用活的风险组 3 株来确定和比较几种市售 LFA 的 LOD。
评估了来自四个不同公司的用于检测以下细菌的侧向流动检测试剂盒：鼠疫耶尔森菌、土拉弗朗西斯菌和炭疽芽孢杆菌孢子。为每个目标生物体应用了两种独立的定量方法，以确保高定量准确性。检测限在测试和生物体之间差异很大，鼠疫耶尔森菌检测的范围为 10，而一个炭疽芽孢杆菌检测的范围高达 >10。
这项工作准确地确定了来自四个商业供应商的 LFA 的 LOD。这里确定的 LOD 与以前的研究结果不同。这说明了使用准确定量的活的风险组 3 株来确定此类 LOD 的必要性。
我们的工作填补了 LFA LOD 方面的重要知识空白。本研究中确定的 LOD 将有助于更好地评估 LFA 结果。它们表明，LFA 的阴性结果不适合排除分析样本中存在相应制剂。
