The ability to detect antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is currently under investigation with various performance characteristics and indications for use. In this article, we analyzed the ability of the Abbott SARS-CoV-2 immunoglobulin class G (IgG), EuroImmun SARS-CoV-2 enzyme-linked immunosorbent assay (ELISA) IgG, and EuroImmun SARS-CoV-2 ELISA immunoglobulin class A (IgA) kits to detect evidence of previous infection with SARS-CoV-2. We tested 49 known coronavirus disease-19 (COVID-19) patients and 111 prepandemic stored serology specimens. This resulted in a sensitivity of 95.9%, 100.0%, and 91.3% and a specificity of 98.2%, 98.2%, and 90.8% respectively, using manufacturer recommended cutoffs after inconclusive results (one for EuroImmun IgG and five for EuroImmun IgA) being excluded in the final statistical analyses. Cross-reactivity of hepatitis C virus seropositive specimens was observed resulting in false positives (p < 0.05). If a two-tiered algorithmic approach was applied, that is, testing with Abbott SARS-CoV-2 assay followed by EuroImmun SARS-CoV-2 IgG, 100% specificity and sensitivity could be obtained after six inconclusive results were excluded from data set before statistical analyses. Performance characteristics presented demonstrate the superior performance of IgG class antibodies for investigating previous infections. In addition, utilizing a second antibody test for supplementary testing may significantly enhance performance, particularly in lower prevalence settings.

中文翻译：

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在纽芬兰和拉布拉多收集的血清中针对SARS-CoV-2的免疫球蛋白A和G类人类抗体的血清学评估

目前正在研究针对严重急性呼吸系统综合症冠状病毒2（SARS-CoV-2）的抗体的检测能力，具有各种性能特征和使用适应症。在本文中，我们分析了Abbott SARS-CoV-2 G类免疫球蛋白（IgG），EuroImmun SARS-CoV-2酶联免疫吸附测定（ELISA）IgG和EuroImmun SARS-CoV-2 ELISA免疫球蛋白A类的能力（IgA）试剂盒可检测先前感染SARS-CoV-2的证据。我们测试了49名已知的冠状病毒病19（COVID-19）患者和111个大流行前存储的血清学标本。这导致敏感性分别为95.9％，100.0％和91.3％，特异性为98.2％，98.2％和90.8％，在最终统计分析中排除了不确定性的结果（一个用于EuroImmun IgG，五个用于EuroImmun IgA）之后，使用制造商建议的临界值。观察到丙型肝炎病毒血清阳性标本的交叉反应性，导致假阳性（p  ＜0.05）。如果采用两层算法，即先用Abbott SARS-CoV-2试验，再用EuroImmun SARS-CoV-2 IgG进行测试，则在从数据集中剔除六个不确定的结果之前，可以获得100％的特异性和敏感性统计分析。提出的性能特征证明了IgG类抗体在调查先前感染方面的优越性能。此外，利用第二抗体测试进行补充测试可能会显着增强性能，尤其是在较低的患病率环境中。