A rapid LASV detection method based on CRISPR-Cas13a and recombinase aided amplification with special lateral-flow test strips

Lassa virus (LASV) is a high-risk pathogen associated with severe viral hemorrhagic fever in both humans and animals. Owing to its significant treatment challenges and high infectivity, LASV is classified as a biosafety level 4 (BSL-4) pathogen. It is essential to establish a rapid LASV detection method to prevent and control the disease. To address the biosecurity threats caused by LASV, in this study, we developed a new test method for LASV detection by combining the recombinase-mediated isothermal amplification (RAA) and CRISPR-Cas13a detection technology. The detection efficiency of this method was evaluated and compared with existing methods. The results demonstrate that this new detection maintains relatively high sensitivity and specificity, while having excellent simplicity and rapidity. The sensitivity of the method for detecting the LASV can achieve a threshold of 10¹ copies/µL using fluorescence detection in 90 min and 10² copies/µL with lateral flow strip detection in just an hour, which only needs a simple constant temperature equipment to achieve. The application of this detection method holds substantial biosecurity significance for underdeveloped regions (e.g., West Africa), as well as for countries like China, which have a vast territory and uneven development of medical testing levels in various regions.