The current gold standard for COVID-19 diagnosis is based on the detection of SARS-CoV-2 nucleic acid using real-time quantitative PCR (RT-qPCR). Recent studies suggest limitations of RT-qPCR in the detection of SARS-CoV-2, possibly leading to false-negative results. Development of robust and sensitive laboratory tests is of primary importance. Naica™ System is a Digital PCR platform offering absolute quantification of nucleic acids withvery high sensitivity and precision. Based on early and successful proof of concept in China, Stilla is developing a SARS-CoV-2 detection kit on the Naica™ System: a highly sensitive and internally controlled SARS-CoV-2 3-plex. It allows detection of two distinct regions: Nucleocapside (N) and ORF1ab genes of the SARS-CoV-2 positive-strand RNA genome, and an endogenous PCR reference detecting a human housekeeping gene.
This single assay design permits the simultaneous detection of two independent SARS-CoV-2 sequences while concurrently monitoring sample PCR effectiveness. Due to its higher sensitivity, Crystal Digital PCR coupled with the detection kit for SARS-CoV-2 should be a perfect alternative to investigate non-conclusive high Ct results obtained in RT-qPCR.

By Romain Parillaud, PhD, International Application Specialist, Stilla Technologies