Clinical performance evaluation of SARS-CoV-2 rapid antigen testing in point of care usage in comparison to RT-qPCR
Isabell Wagenhäuser, Kerstin Knies, Vera Rauschenberger, Michael Eisenmann, Miriam McDonogh, Nils Petri, Oliver Andrés, Sven Flemming, Micha Gawlik, Michael Papsdorf, Regina Taurines, Hartmut Böhm, Johannes Förster, Dirk Weismann, Benedikt Weißbrich, Lars Dölken, Johannes G. Liese, Oliver Kurzai, Ulrich Vogel, Manuel Krone
Abstract
Background: Antigen rapid diagnostic tests (RDT) for SARS-CoV-2 are fast, broadly available, and inexpensive. Despite this, reliable clinical performance data from large field studies is sparse. Methods: In a prospective performance evaluation study, RDT from three manufacturers (NADAL , Panbio TM , MEDsan , conducted on different samples) were compared to quantitative reverse transcription polymerase chain reaction (RT-qPCR) in 5 068 oropharyngeal swabs for detection of SARS-CoV-2 in a hospital setting. Viral load was derived from standardised RT-qPCR Cycle threshold (C t ) values. The data collection period ranged from November 12, 2020 to February 28, 2021. Findings: The sensitivity of RDT compared to RT-qPCR was 4257% (95% CI 3338%5231%). The specificity was 9968% (95% CI 9948%9980%). Sensitivity declined with decreasing viral load from 100% in samples with a deduced viral load of 10 8 SARS-CoV-2 RNA copies per ml to 882% in samples with a viral load lower than 10 4 SARS-CoV-2 RNA copies per ml. No significant differences in sensitivity or specificity could be observed between samples with and without spike protein variant B.1.1.7. The NPV in the study cohort was 9884%; the PPV in persons with typical COVID-19 symptoms was 9737%, and 2857% in persons without or with atypical symptoms. Interpretation: RDT are a reliable method to diagnose SARS-CoV-2 infection in persons with high viral load. RDT are a valuable addition to RT-qPCR testing, as they reliably detect infectious persons with high viral loads before RT-qPCR results are available.