Twelve lateral flow immunoassays (LFAs) to detect SARS-CoV-2 antibodies

Owen, Sophie I. and Williams, Christopher T. and Garrod, Gala and Fraser, Alice J. and Menzies, Stefanie and Baldwin, Lisa and Brown, Lottie and Byrne, Rachel L. and Collins, Andrea M. and Cubas-Atienzar, Ana I. and de Vos, Margaretha and Edwards, Thomas and Escadafal, Camille and Ferreira, Daniela M. and Fletcher, Tom and Hyder-Wright, Angela and Kay, Grant A. and Kontogianni, Konstantina and Mason, Jenifer and Mitsi, Elena and Planche, Tim and Sacks, Jilian A. and Taylor, Joseph and Todd, Stacy and Tully, Caroline and Cuevas, Luis E. and Adams, Emily R. (2022) Twelve lateral flow immunoassays (LFAs) to detect SARS-CoV-2 antibodies. Journal of Infection, 84 (3). pp. 355-360. ISSN 0163-4453

Abstract

Background: There are an abundance of commercially available lateral flow assays (LFAs) that detect antibodies to SARS-CoV-2. Whilst these are usually evaluated by the manufacturer, externally performed diagnostic accuracy studies to assess performance are essential. Herein we present an evaluation of 12 LFAs. Methods: Sera from 100 SARS-CoV-2 reverse-transcriptase polymerase chain reaction (RT-PCR) positive participants were recruited through the FASTER study. A total of 105 pre-pandemic sera from participants with other infections were included as negative samples. Results: At presentation sensitivity against RT-PCR ranged from 37.4 to 79% for IgM/IgG, 30.3–74% for IgG, and 21.2–67% for IgM. Sensitivity for IgM/IgG improved ≥ 21 days post symptom onset for 10/12 tests. Specificity ranged from 74.3 to 99.1% for IgM/IgG, 82.9–100% for IgG, and 75.2–98% for IgM. Compared to the EuroImmun IgG enzyme-linked immunosorbent assay (ELISA), sensitivity and specificity ranged from 44.6 to 95.4% and 85.4–100%, respectively. Conclusion: There are many LFAs available with varied sensitivity and specificity. Understanding the diagnostic accuracy of these tests will be vital as we come to rely more on the antibody status of a person moving forward, and as such manufacturer-independent evaluations are crucial.