Direct NP- A cost-effective extraction-free RT-qPCR based test for SARS-CoV-2
Rasesh Y. Parikh,
Satish N. Nadig,
Shikhar Mehrotra,
Philip H. Howe,
Vamsi K. Gangaraju
Affiliations
Rasesh Y. Parikh
Department of Biochemistry and Molecular Biology, Hollings Cancer Center, Medical University of South Carolina, Charleston, SC 29425, USA; Corresponding author.
Satish N. Nadig
Department of Surgery, Hollings Cancer Center, Medical University of South Carolina, Charleston, SC 29425, USA
Shikhar Mehrotra
Department of Surgery, Hollings Cancer Center, Medical University of South Carolina, Charleston, SC 29425, USA; Department of Microbiology & Immunology, Hollings Cancer Center, Medical University of South Carolina, Charleston, SC 29425, USA
Philip H. Howe
Department of Biochemistry and Molecular Biology, Hollings Cancer Center, Medical University of South Carolina, Charleston, SC 29425, USA
Vamsi K. Gangaraju
Department of Biochemistry and Molecular Biology, Hollings Cancer Center, Medical University of South Carolina, Charleston, SC 29425, USA; Corresponding author.
Over 2.4 million daily total tests are currently being performed for SARS-CoV-2, in the United States. The most common SARS-CoV-2 tests require RNA extraction and purification. Extraction of RNA is a time-consuming and costly step that requires a constant supply of reagents and accessories. With the current testing demand, the supply chain remains the bottleneck for RNA extraction. Here, we report Direct NP- a cost-effective extraction-free RT-qPCR based dualplex test for SARS-CoV-2 from Nasopharyngeal (NP) swab specimens. Direct NP detects SARS-CoV-2 viral RNA from heat-denatured patient specimens using a dualplex RT-qPCR assay. Direct NP showed 92.5% positive percentage agreement (PPA) (95% Confidence Interval (CI) = 79.61%–98.43%) and 97% negative percent agreement (NPA) (95% CI = 89.11–100%) with the CDC assay. Direct NP reduces the cost per test to $2, making it suitable for broad-scale testing while lowering the cost burden on the healthcare system.
