A Scalable, Easy-to-Deploy, Protocol for Cas13-Based Detection of SARS-CoV-2 Genetic Material

Jennifer N Rauch; Eric Valois; Sabrina C Solley; Friederike Braig; Ryan S Lach; Naomi J Baxter; Kenneth S Kosik; Carolina Arias; Diego Acosta-Alvear; Maxwell Z Wilson

Cas12 and Cas13 (CRISPR-based) methods have been transformative with regards to pathogen detection. They are sensitive and, when coupled to isothermal amplification methods and lateral flow immunochromatography detection, have been made field deployable. These methods are promising tools for the detection of SARS-CoV-2 [15] [16] [17] [18] . Yet, because of the global demand for testing, key reagents in these protocols are difficult to obtain. To lower the barrier to COVID-19 diagnostics, we devised a method we call CREST (Cas13-based, Rugged, Equitable, Scalable Testing). CREST addresses three of the main hurdles-reagent accessibility, equipment availability, and cost-that limit the scalability of Cas13-based testing, by taking advantage of widely available enzymes, low-cost thermocyclers, and easy-to-use fluorescent visualizers. Moreover, CREST is equivalent in sensitivity to the gold standard reverse transcription quantitative polymerase chain reaction (RT-qPCR) method most often deployed for COVID-19 testing. With these advantages, CREST has the potential to facilitate early detection of positive cases, regular monitoring of individuals at high risk, and implementation of informed containment measures for infected individuals.