Background: Rapid identification and effective isolation are crucial for curbing the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). To meet this requirement, antigen-detection rapid diagnostic tests (Ag-RDTs) are essential. Methods: Between February 2020 and August 2020 we performed a cohort study of patients with confirmed COVID-19. The clinical performance of Ag rapid fluorescence immunoassay (FIA) and Ag Gold was evaluated and compared in parallel with genomic and subgenomic real-time reverse transcription-polymerase chain reaction (rRT-PCR) and cell culture-based assays. Results: In total, 150 samples were tested. Of these, 63 serial samples were obtained from 11 patients with SARS-CoV-2 and 87 from negative controls. Serial respiratory samples were obtained 2 days prior to symptom onset (-2) up to 25 days post-symptom onset. Overall, for rRT-PCR-positive samples ( n = 51), the detection sensitivity of Ag rapid FIA and Ag Gold was 74.5% and 53.49%, respectively, with a specificity of 100%; however, for samples with low cycle threshold (Ct) values, Ag rapid FIA and Ag Gold exhibited a sensitivity of 82.61% (Ct ≤ 30, 5.6 log 10 RNA copies/mL) and 80% (Ct ≤ 25, 6.9 log 10 RNA copies/mL), respectively. Despite low analytical sensitivity, both Ag-RDTs detected 100% infection in cell culture-positive samples ( n = 15) and were highly effective in distinguishing viable samples from those with subgenomic RNA (66.66%). For both Ag-RDTs, all samples that yielded discordant results (rRT-PCR + ve/Ag-RDT -ve) were also negative by culture. Conclusion: The data suggest that Ag-RDTs reliably detect viable SARS-CoV-2; thus, they may serve as an important tool for rapid detection of potentially infectious individuals.
【저자키워드】 SARS-CoV-2, Infectivity, PCR, subgenomic RNA, Cell culture, Ag-RDT, genomic RNA, 【초록키워드】 COVID-19, coronavirus, Infection, cohort study, RNA, Spread, immunoassay, sensitivity, specificity, rRT-PCR, Culture, Rapid diagnostic test, cycle threshold, Patient, Isolation, Rapid, gold, genomic, analytical sensitivity, Detection sensitivity, symptom onset, acute respiratory syndrome, negative controls, post-symptom onset, Ag-RDTs, effective, Cell, respiratory sample, log, tested, performed, detect, assays, evaluated, exhibited, individuals, antigen-detection, patients with SARS-CoV-2, 【제목키워드】 coronavirus 2, RNA, Rapid, respiratory, isolate, Viable,