Assay Validation for SARS-CoV-2 Antibody Detection

Based on samples from 63 COVID-19 survivors up to seven months after symptom onset, and on 50 serum samples taken before the beginning of the pandemic, we compared the performance of three commercial immunoassays for the detection of SARS-CoV-2 IgA and IgG antibodies and three rapid lateral flow (immunochromatographic) tests with a plaque-reduction neutralization test representing the gold standard. In addition, we report and validate a novel, non-commercial flow cytometry bead-based surrogate test.
57 out of 63 PCR-confirmed COVID-19 patients (90 %) showed neutralizing antibodies. The 35 sensitivity of the seven assays ranged from 7.0 % to 98.3 %, the specificity from 86.0 % to 36 100.00 %. Only one commercial immunoassay showed a sensitivity and specificity of greater than 98 %. These data indicate abundant interassay variability.

Manuel Krone, Julia Gütling, Johannes Wagener, Thiên-Trí Lâm, Chrsitoph Schoen, Ulrich Vogel, August Stich, Florian Wedekink, Jörg Wischhusen, Thomas Kerkau, Niklas Beyersdorf, Silvana Klingler, Simone Backes, Lars Dölken, Georg Gasteiger, Oliver Kurzai and Alexandra Schubert-Unkmeir

Performance of three SARS-CoV-2 immunoassays, three 1 rapid lateral flow tests and a novel bead-based affinity 2 surrogate test for the detection of SARS-CoV-2 antibodies 3 in human serum

https://www.medrxiv.org/content/10.1101/2021.02.07.21251062v1