Rapid and Safe Detection of SARS-CoV-2 and Influenza Virus RNA using Onsite qPCR Diagnostic Testing from Clinical Specimens Collected in Molecular Transport Medium

Daum, Luke T; Fischer, Gerald W

BACKGROUND: The ability to rapidly detect SARS-CoV-2 and influenza virus infection is vital for patient care due to overlap in clinical symptoms. Roche’s cobas® Liat(®) SARS-CoV-2 & Influenza A/B Nucleic Acid Test used on the cobas(®) Liat(®) was granted approval under FDA’s Emergency Use Authorization (EUA) for nasopharyngeal (NP) and nasal swabs collected in viral/universal transport medium (VTM/UTM). However, there is a critical need for media that inactivates the virus, especially when specimens are collected in decentralized settings. This study aimed to investigate the use of PrimeStore Molecular Transport Medium(®) (PS-MTM(®)), designed to inactivate/kill and stabilize RNA/DNA for ambient transport and pre-processing of collected samples. METHODS: A limit of detection (LOD) using serially diluted SARS-CoV-2 RNA in PS-MTM(®) and routine UTM was established using standard qPCR. Additionally, a clinical panel of NP and oral swabs collected in PS-MTM(®) collected during the 2020 coronavirus disease 2019 (COVID-19) pandemic were evaluated on the cobas(®) Liat(®) and compared to ‘gold standard’ qPCR on an ABI-7500 instrument. RESULTS: SARS-CoV-2 RNA LOD using standard qPCR was equivalent on the cobas(®) Liat(®) instrument. cobas(®) Liat(®) detection from oral/NP swabs in PS-MTM(®) media exhibited equivalent positive percent agreement (100%) and negative percent agreement (96.4%). CONCLUSION: PS-MTM(®) and the Roche cobas(®) Liat(®) are compatible and complimentary devices for respiratory specimen collection and rapid disease detection, respectively. PS-MTM(®) is equivalent to standard VTM/UTM with the added benefit of safe, non-infectious sample processing for near-patient testing.