Table 1. Specification of three commercial real-time RT-PCR kits for the multiplex detection of SARS-CoV-2, influenza virus A/B, and/or RSV.
| Variables | Kit name | ||
|---|---|---|---|
| PowerChek™ SARS-CoV-2, Influenza A&B Multiplex Real-time PCR Kit (KogeneBiotech) | STANDARD™ M Flu/SARS-CoV-2 Real-time Detection Kit (SD BioSensor) | Allplex™ SARS-CoV-2/FluA/FluB/RSV Assay (Seegene) | |
| Target genes (virus) | ORF1ab, E (SC2), M (influenza A), NP (influenza B) | ORF1ab, E (SC2), M (influenza A), NS1 (influenza B) | N, RdRp, S (SC2), M (influenza A), NS (influenza B), M (RSV) |
| Internal control | RNA process control, spiked into sample or 0.5 μL into PCR mixture | Recombinant RNA (Turnip yellow mosaic virus), 5 μL spiked into sample or 0.5 μL into PCR mixture | RNAse P (Endo IC) MS2 phage (Exo IC), spiked into sample |
| Applicable PCR analyzer | CFX96 Real-time PCR Detection System (Bio-Rad), Gentier 96S Real-time PCR System (Tianlong) | CFX96™ Dx System (Bio-Rad), Rotor-Gene Q (Qiagen) | CFX96™ Dx System (Bio-Rad) |
| Volume of nucleic acid extracts/PCR reaction mixtures per test, μL | 5/15 | 10/20 | 10/10 |
| No. of pre-amplification/amplification cycles | None/40 | 5/40 | 3/42 |
| PCR running time, min | 120 | 90 | 115 |
| Cut off for positive (Ct) | 38, 35 for IC | 36 | 38, 40 for RdRp |
| Sample types | Nasopharyngeal swab | Sputum, nasopharyngeal swab, oropharyngeal swab | Nasopharyngeal swab |
All kits are one-step RT-PCR kits. Pre-amplification was not counted for Ct.
RT-PCR = reverse transcription polymerase chain reaction, SARS-CoV-2 = severe acute respiratory syndrome-coronavirus-2, RSV = respiratory syncytial virus, SC2 = SARS-CoV-2, IC = internal control, exo IC = exogenous internal control, endo IC = endogenous internal control, Ct = cycle threshold.