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1.
Preprint in English | medRxiv | ID: ppmedrxiv-21256786

ABSTRACT

BackgroundCOVID-19 pandemic interrupted routine care for individuals living with HIV, putting them at risk of becoming virologically unsuppressed and ill. Often they are at high risk for exposure to SARS-CoV-2 infection and severe disease once infected. For this population, it is urgent to closely monitor HIV plasma viral load (VL) and screen for SARS-COV-2 infection. MethodWe have developed a non-proprietary method to isolate RNA from plasma, nasal secretions (NS), or both. HIV, SARS-CoV-2, and human RP targets in extracted RNA are then RT-qPCR to estimate the VL and classify HIV/SARS-CoV-2 status (i.e., HIV as VL failure or suppressed; SARS-CoV-2 as positive, presumptive positive, negative, or indeterminate). We evaluated this workflow on 133 clinical specimens: 40 plasma specimens (30 HIV-seropositive), 67 NS specimens (31 SARS-CoV-2-positive), and 26 pooled plasma/NS specimens (26 HIV-positive with 10 SARS-CoV-2-positive), and compared the results obtained using the in-house extraction to those using a commercial extraction kit. ResultsIn-house extraction had a detection limit of 200-copies/mL for HIV and 100-copies/mL for SARS-CoV-2. In-house and commercial methods yielded positively correlated HIV VL (R2: 0.98 for contrived samples; 0.81 for seropositive plasma). SARS-CoV-2 detection had 100% concordant classifications in contrived samples, and in clinical NS extracted by in-house method, excluding indeterminate results, was 95% concordant (25 positives, 6 presumptive positives, and 31 negatives) to those using the commercial method. Analysis of pooled plasma/NS showed R2 of 0.91 (contrived samples) and 0.71 (clinical specimens) for HIV VL correlations obtained by both extraction methods, while SARS-CoV-2 detection showed 100% concordance in contrived and clinical specimens. InterpretationOur low-cost workflow for molecular testing of HIV and SARS-CoV-2 could serve as an alternative to current standard assays for laboratories in low-resource settings.

2.
Preprint in English | medRxiv | ID: ppmedrxiv-21261875

ABSTRACT

RNA amplification tests allow sensitive detection of 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 that processes up to 4 samples simultaneously. Our lyophilized reverse-transcription, loop-mediated isothermal amplification (RT-LAMP) can detect as little as 15 SARS-CoV-2 RNA copies per reaction, and it can report as early as 17 min for samples with high viral load (2 x 105 RNA copies per reaction). Analysis of RNA extracted from clinical nasal specimens (n = 101) showed 95% concordance with RT-PCR, including 100% specificity in specimens positive for other viruses and bacteria. Analysis of contrived samples in the nasal matrix showed detection of 92% or 100% in samples with [≥]20 or [≥]100 particles per reaction, respectively. Usability testing showed 95% accuracy by healthcare workers operating the test for the first time. ONE SENTENCE SUMMARYHarmony COVID-19: point-of-care SARS-CoV-2 RNA detection

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