Development and validation of a single-step reverse transcriptase rapid loop-mediated isothermal amplification (RT-LAMP) system potentially to be used for reliable and high- throughput screening of COVID-19 Running title: Rapid diagnosis of COVID-19 by a LAMP assay

The recent pandemic of COVID-19 has involved tens of thousands of patients in numerous countries and the causative virus, SARS COV-2 is highly transmissible. Molecular diagnostic tools are central to containment of the virus and initiating proper clinical care. Rapidity, userfriendliness, and high degree of sensitivity and specificity are desirable features of diagnostic assays for screening purposes. Herein, we present a single step reverse transcriptase LAMP assay (RT-LAMP), which can detect up to 500 viral copies in 30 minutes. We challenged our assay with a large number of clinical samples collected from 47 confirmed cases and 213 negative patients. Our LAMP assay showed a high degree of sensitivity and specificity compared to two commercialized qRT-PCR assay as gold standard. We present a rapid RTLAMP assay that could extend the capacity of laboratories to process 2.5 more clinical samples relative to qRT-PCR and potentially could be used for high-throughput screening purposes.