Hospital Karvina-Raj, Vydmuchov 399, 734 01 Karvina, Czech Republic.
Department of Internal Medicine, Faculty of Medicine, University of Ostrava, Syllabova 19, 703 00 Ostrava, Czech Republic.
Viruses. 2021 Apr 15;13(4):684. doi: 10.3390/v13040684.
Antigen testing for SARS-CoV-2 (AGT) is generally considered inferior to RT-PCR testing in terms of sensitivity. However, little is known about the infectiousness of RT-PCR positive patients who pass undetected by AGT. In a screening setting for mildly symptomatic or asymptomatic patients with high COVID-19 prevalence (30-40%), 1141 patients were tested using one of five AGTs and RT-PCR. Where the results differed, virus viability in the samples was tested on cell culture (CV-1 cells). The test battery included AGTs by JOYSBIO, Assure Tech, SD Biosensor, VivaChek Biotech and NDFOS. Sensitivities of the ATGs compared to RT-PCR ranged from 42% to 76%. The best test yielded a 76% sensitivity, 97% specificity, 92% positive, and 89% negative predictive values, respectively. However, in the best performing ATG tests, almost 90% of samples with "false negative" AGT results contained no viable virus. Corrected on the virus viability, sensitivities grew to 81-97% and, with one exception, the tests yielded high specificities >96%. Performance characteristics of the best test after adjustment were 96% sensitivity, 97% specificity, 92% positive, and 99% negative predictive values (high prevalence population). We, therefore, believe that virus viability should be considered when assessing the AGT performance. Also, our results indicate that a well-performing antigen test could in a high-prevalence setting serve as an excellent tool for identifying patients shedding viable virus. We also propose that the high proportion of RT-PCR-positive samples containing no viable virus in the group of "false negatives" of the antigen test should be further investigated with the aim of possibly preventing needless isolation of such patients.
针对严重急性呼吸系统综合征冠状病毒 2 型（SARS-CoV-2）的抗原检测（AGT）在灵敏度方面通常被认为劣于 RT-PCR 检测。然而，对于通过 AGT 检测漏检的 RT-PCR 阳性患者的传染性知之甚少。在一项针对高 COVID-19 流行率（30-40%）的轻度症状或无症状患者的筛查环境中，使用五种 AGT 和 RT-PCR 对 1141 名患者进行了检测。对结果不同的样本，在细胞培养（CV-1 细胞）上测试了病毒的存活能力。检测试剂盒包括 JOYSBIO、AssureTech、SD Biosensor、VivaChek Biotech 和 NDFOS 的 AGT。与 RT-PCR 相比，AGT 的灵敏度范围为 42%至 76%。表现最好的测试分别产生了 76%的灵敏度、97%的特异性、92%的阳性预测值和 89%的阴性预测值。然而，在表现最好的 AGT 检测中，近 90%的“假阴性”AGT 结果样本中没有存活病毒。对病毒存活能力进行校正后，灵敏度增长至 81-97%，除了一个例外，这些检测的特异性均>96%。校正后，表现最好的测试的性能特征为 96%的灵敏度、97%的特异性、92%的阳性预测值和 99%的阴性预测值（高流行人群）。因此，我们认为在评估 AGT 性能时应考虑病毒存活能力。此外，我们的结果表明，在高流行环境中，性能良好的抗原检测可以作为识别有活病毒排出的患者的极好工具。我们还建议进一步研究抗原检测“假阴性”组中 RT-PCR 阳性样本中大量无存活病毒的原因，以便可能避免对这些患者进行不必要的隔离。
