C4COVID-19 Human: A Rapid SARS-Cov-2 Salivary Test Compared to the Gold Standard – Clinical Results

Abstract

The SARS-CoV-2 detection campaign is a key element in the viral pandemic response. Here we present a monocentric study to evaluate a simplified molecular amplification technology alternative to classical RT-qPCR platforms. The test, C4Covid-19 HumanTM makes use of saliva as a starting sample allowing for self, painless collection, avoiding risk of viral transmission for the operator who performs the nasopharyngeal (NP) procedure. Total time to result is 30 minutes. The principle relies on an extraction-free detection of two targets within the viral genomic RNA, RdRp and N genes, by real-time reverse transcription loop mediated isothermal amplification (RT-LAMP). Saliva and NP swabs were collected simultaneously from 1491 symptomatic or contact cases and analyzed in parallel by RT-LAMP and RT-qPCR respectively. The 249 positives RT-qPCR samples had a Ct <37. Sensitivity and specificity of RT-LAMP were 85.7% (95% CI 80.4 to 89.7) and 97.3% (95% CI 96.1 to 98.1) respectively. Among the total cohort, the 56.9% of asymptomatic subjects showed higher sensitivity (90.6% with a 95% CI of 81.0 to 95.6) while specificity remained unchanged (97.4% with a 95% CI of 95.6 to 98.4). C4Covid-19 HumanTM is a rapid, simple and reliable SARS-CoV-2 detection test for population screening.