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

Sophie I Owen ,Camille Escadafal,Lisa Baldwin,Gala Garrod,Thomas Edwards,Tom Fletcher,Luis E Cuevas,Margaretha De Vos,Konstantina Kontogianni,Angela Hyder-Wright,Elena Mitsi,Daniela M Ferreira,Tim Planche,Stacy Todd,Jilian A Sacks,Caroline Tully,Lottie Brown,Ana I Cubas Atienzar ,Andrea Collins ,J H Mason ,Joseph M Taylor ,Rachel L Byrne ,Grant A Kay ,Christopher T Williams ,Stefanie K Menzies ,Alice Fraser ,Emily Adams

doi:10.1016/j.jinf.2021.12.007

Abstract

BackgroundThere 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. MethodsSera 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. ResultsAt 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. ConclusionThere 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.

Highlights

As of May 2021, there have been over 100,000,000 confirmed cases of COVID-19 worldwide, the total number of cases is much higher.[1]
There is a plethora of lateral flow assays (LFAs) available on the market today, all purporting to offer high sensitivity and specificity, but often without rigorous, manufacturer-independent evaluations
We demonstrate the differences in sensitivity and specificity of the responses of combined IgM/IgG, IgG and IgM against a RT-qPCR and an IgG enzyme-linked immunosorbent assay (ELISA), in patients presenting with both acute and convalescent SARS-CoV-2 infections

Summary

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. 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. 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. 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. 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

Introduction

Ethics statement

Participants

Results

Discussion

Declaration of Competing Interest