The comparative clinical performance of four SARS-CoV-2 rapid antigen tests and their correlation to infectivity in vitro

  • Due to globally rising numbers of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections, resources for real-time reverse-transcription polymerase chain reaction (rRT-PCR)-based testing have been exhausted. In order to meet the demands of testing and reduce transmission, SARS-CoV-2 antigen-detecting rapid diagnostic tests (Ag-RDTs) are being considered. These tests are fast, inexpensive, and simple to use, but whether they detect potentially infectious cases has not been well studied. We evaluated three lateral flow assays (RIDA®QUICK SARS-CoV-2 Antigen (R-Biopharm), SARS-CoV-2 Rapid Antigen Test (Roche)), and NADAL® COVID-19 Ag Test (Nal von Minden GmbH, Regensburg, Germany) and one microfluidic immunofluorescence assay (SARS-CoV-2 Ag Test (LumiraDx GmbH, Cologne, Germany)) using 100 clinical samples. Diagnostic rRT-PCR and cell culture testing as a marker for infectivity were performed in parallel. The overall Ag-RDT sensitivity for rRT-PCR-positive samples ranged from 24.3% to 50%. However, for samples with a viral load of more than 6 log10 RNA copies/mL (22/100), typically seen in infectious individuals, Ag-RDT positivity was between 81.8% and 100%. Only 51.6% (33/64) of the rRT-PCR-positive samples were infectious in cell culture. In contrast, three Ag-RDTs demonstrated a more significant correlation with cell culture infectivity (61.8–82.4%). Our findings suggest that large-scale SARS-CoV-2 Ag-RDT-based testing can be considered for detecting potentially infective individuals and reducing the virus spread.
Author:Niko Kohmer, Tuna Toptan, Christiane Pallas, Onur Karaca, Annika Pfeiffer, Sandra Westhaus, Marek WideraORCiDGND, Annemarie Berger, Sebastian HoehlORCiDGND, Martin Kammel, Sandra CiesekORCiDGND, Holger F. Rabenau
Parent Title (English):Journal of clinical medicine
Place of publication:Basel
Document Type:Article
Date of Publication (online):2021/01/17
Date of first Publication:2021/01/17
Publishing Institution:Universitätsbibliothek Johann Christian Senckenberg
Release Date:2021/04/15
Tag:Ag-RDT; PCR; POCT; SARS-CoV-2; cell culture; infectivity
Issue:2, art. 328
Page Number:11
First Page:1
Last Page:11
Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (
Dewey Decimal Classification:6 Technik, Medizin, angewandte Wissenschaften / 61 Medizin und Gesundheit / 610 Medizin und Gesundheit
Licence (German):License LogoCreative Commons - Namensnennung 4.0