Reliable Diagnostics of SARS-CoV-2 Infections Using One- and Two-Gene Molecular Tests for a Viral RNA Detection-Results Questioning Previous Observations

Abstract

SARS-CoV-2 is a new virus from the Coronaviridae family and its rapid spread is now the most important medical problem worldwide. Currently used tests vary in the number and selection of SARS-CoV-2 target genes. Meanwhile, the choice of the appropriate target gene may be important in terms of a reliable detection of a viral RNA. As some researchers questioned the sensitivity of the monogenic VIASURE SARS-CoV-2 S gene Real Time PCR Detection Kit (CerTest Biotec, Zaragoza, Spain) in mid-2020, the aim of the study was to evaluate the usefulness of this kit, used along with the BD MAX™ System (Becton Dickinson, East Rutherford, NJ, USA), and compare the results with two-gene Bosphore Novel Coronavirus (2019-nCoV) Detection Kit v1 (Anatolia Diagnostics and Biotechnology Products Inc., Istanbul, Turkey). Both tests were carried out on 306 nasopharyngeal/oropharyngeal swabs. The consistent results (72 positive and 225 negative results found simultaneously in both kits) were obtained for 297 (97.1%) samples altogether, while discrepancies between the results of the evaluated tests were observed for nine (2.9%) specimens. There were no statistically significant differences between the method used and the frequency of positive results. Both tests, targeted at detecting one and two genes, are effective in SARS-CoV-2 RNA detection.

Keywords: 2019-nCoV; BD MAX™ System; COVID-19; E gene; ORF1ab gene; RNA detection; S gene; SARS-CoV-2.

Figure 1

The examples of false negative results from BD MAX™ System (A–D); blue lines represent the threshold line.

Figure 2

True positive results on BD MAX™ System which were inconclusive (A–C) or negative (D) using Bosphore Novel Coronavirus kit (2019-nCoV) Detection Kit v1.