The December 2019 outbreak of a novel respiratory virus, SARS-CoV-2, has become an ongoing global pandemic due in part to the challenge of identifying symptomatic, asymptomatic, and pre-symptomatic carriers of the virus. CRISPR diagnostics can augment gold-standard PCR-based testing if they can be made rapid, portable, and accurate. Here, we report the development of an amplification-free CRISPR-Cas13a assay for direct detection of SARS-CoV-2 from nasal swab RNA that can be read with a mobile phone microscope. The assay achieved ∼100 copies/μL sensitivity in under 30 min of measurement time and accurately detected pre-extracted RNA from a set of positive clinical samples in under 5 min. We combined crRNAs targeting SARS-CoV-2 RNA to improve sensitivity and specificity and directly quantified viral load using enzyme kinetics. Integrated with a reader device based on a mobile phone, this assay has the potential to enable rapid, low-cost, point-of-care screening for SARS-CoV-2.

2019年12月，新型呼吸道病毒SARS-CoV-2爆发已成为全球性大流行病，部分原因是要确定该病毒的症状，无症状和症状前携带者。CRISPR诊断程序可以快速，便携和准确地进行，因此可以增强基于金标准的基于PCR的测试。在这里，我们报告了一种免扩增的CRISPR-Cas13a检测技术的发展，该检测技术可直接从鼻拭子RNA中直接检测SARS-CoV-2，可通过手机显微镜对其进行读取。该测定法在30分钟的测量时间内即可达到约100拷贝/μL的灵敏度，并能在5分钟内准确检测出一组阳性临床样品中的预提取RNA。我们结合靶向SARS-CoV-2 RNA的crRNA来提高敏感性和特异性，并使用酶动力学直接定量病毒载量。