A Rapid, High-Sensitivity SARS-CoV-2 Nucleocapsid Immunoassay to Aid Diagnosis of Acute COVID-19 at the Point of Care: A Clinical Performance Study

• DOI: 10.1007/s40121-021-00413-x
• Publication Date: 2021-02-24T18:02:58Z
• Authors: Paul K. Drain; Madhavi Ampajwala; Christopher Chappel; Andre B. Gvozden; Melanie Hoppers; Melody Wang; Robert Rosen; Stephen Young; Edward Zissman; Michalina Montano
• Keywords: Point-of-Care Testing; Point of care; Gold standard (test)

The LumiraDx severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antigen test, which uses a high-sensitivity, microfluidic immunoassay to detect the nucleocapsid protein of SARS-CoV-2, was evaluated for diagnosing disease 2019 (COVID-19) in adults and children across point-of-care settings (NCT04557046). Two paired anterior nasal swabs or two nasopharyngeal were collected from each participant. Swabs tested by SARS-CoV-2 test compared with real-time polymerase chain reaction (rt-PCR; Roche cobas 6800 platform). Sensitivity, specificity likelihood ratios calculated. Results stratified on basis gender, age, duration symptoms, rt-PCR cycle threshold. Out 512 participants, aged 0–90 years, this prospective validation study, 414 (81%) symptomatic COVID-19 123 (24%) positive based testing. Compared rt-PCR, 12-min swab had 97.6% sensitivity 96.6% specificity, 97.5% 97.7% within 12 days symptom onset, representing period infectivity. All (100%) samples detected 33 cycles also identified using test. consistent age gender. user error rate system when used minimally trained operators 0.7% (95% confidence interval [CI] 0.1–3.7%). rapid, high-sensitivity assay sampling may offer significant improvements infection clinic- community-based settings.