Real-world evaluation of a novel technology for quantitative simultaneous antibody detection against multiple SARS-CoV-2 antigens in a cohort of patients presenting with COVID-19 syndrome
Andrew M. Shaw, Christopher Hyde, Blair Merrick, Philip H. James‐Pemberton, Bethany K. Squires, Rouslan V. Olkhov, Rahul Batra, Amita Patel, Karen Bisnauthsing, Gaia Nebbia, Eithne MacMahon, Sam Douthwaite, Michael H. Malim, Stuart J. D. Neil, Rocio Martinez Nunez, Katie J. Doores, Mark Tan Kia Ik, Adrian W. Signell, Gilberto Betancor, Harry Wilson, Rui Pedro Galão, Suzanne Pickering, Jonathan D. Edgeworth
Abstract
An evaluation of a rapid portable gold-nanotechnology measuring SARS-CoV-2 IgM, IgA and IgG antibody concentrations against spike 1 (S1), spike 2 (S) and nucleocapsid (N) was conducted using serum samples from 74 patients tested for SARS-CoV-2 RNA on admission to hospital, and 47 historical control patients from March 2019. 59 patients were RNA(+) and 15 were RNA(-). A serum (±) classification was derived for all three antigens and a quantitative serological profile was obtained. Serum(+) was identified in 30% (95% CI 11-48) of initially RNA(-) patients, in 36% (95% CI 17-54) of RNA(+) patients before 10 days, 77% (95% CI 67-87) between 10 and 20 days and 95% (95% CI 86-100) after 21 days. The patient-level diagnostic accuracy relative to RNA(±) after 10 days displayed 88% sensitivity (95% CI 75-95) and 75% specificity (95% CI 22-99), although specificity compared with historical controls was 100% (95%CI 91-100). This study provides robust support for further evaluation and validation of this novel technology in a clinical setting and highlights challenges inherent in assessment of serological tests for an emerging disease such as COVID-19.