Establishment of a quantitative RT-PCR detection of SARS-CoV-2 virus.

Background: The outbreak of novel coronavirus disease 2019 (COVID-19) has become a public health emergency of international concern. Quantitative testing of SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) virus is demanded in evaluating the efficacy of antiviral drugs and vaccines and RT-PCR can be widely deployed in the clinical assay of viral loads. Here, we developed a quantitative RT-PCR method for SARS-CoV-2 virus detection in this study.

Methods: RT-PCR kits targeting E (envelope) gene, N (nucleocapsid) gene and RdRP (RNA-dependent RNA polymerase) gene of SARS-CoV-2 from Roche Diagnostics were evaluated and E gene kit was employed for quantitative detection of COVID-19 virus using Cobas Z480. Viral load was calculated according to the standard curve established by series dilution of an E-gene RNA standard provided by Tib-Molbiol (a division of Roche Diagnostics). Assay performance was evaluated.

Results: The performance of the assay is acceptable with limit of detection (LOD) below 10E1 copies/μL and lower limit of quantification (LLOQ) as 10E2 copies/μL.

Conclusion: A quantitative detection of the COVID-19 virus based on RT-PCR was established.