Direct NP- A cost-effective extraction-free RT-qPCR based test for SARS-CoV-2

Abstract

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.