Harmony COVID-19: a ready-to-use kit, low-cost detector, and smartphone app for point-of-care SARS-CoV-2 RNA detection
RNA amplification tests sensitively detect SARS-CoV-2 infection, but their complexity and cost are prohibitive for expanding COVID-19 testing. We developed Harmony COVID-19, a point-of-care test using inexpensive consumables, ready-to-use reagents, and a simple device accommodating up to 4 samples simultaneously. Our ready-to-use, 4-plex reverse-transcription, loop-mediated isothermal amplification (RT-LAMP) can detect down to 0.38 SARS-CoV-2 RNA copies/μL and can report in 17 min for high viral load samples (5,000 copies/μL). Harmony detected 97% or 83% of contrived samples with ≥0.5 viral particles/μL in nasal matrix or saliva, respectively. Evaluation in clinical nasal specimens in viral transport media (VTM, n=101) showed 100% detection of RNA extracted from specimens with ≥0.5 SARS-CoV-2 RNA copies/μL, with 100% specificity in specimens positive for other respiratory pathogens. VTM is non-ideal for Harmony system, yet extraction-free analysis of VTM specimens (n=29) had 95% success in specimens with ≥1 RNA copies/μL. Usability testing performed first-time by healthcare workers showed 95% accuracy