Validity of Self-testing at Home With Rapid Severe Acute Respiratory Syndrome Coronavirus 2 Antibody Detection by Lateral Flow Immunoassay

Christina J Atchison; Maya Moshe; Jonathan C Brown; Matthew Whitaker; Nathan C K Wong; Anil A Bharath; Rachel A McKendry; Ara Darzi; Deborah Ashby; Christl A Donnelly; Steven Riley; Paul Elliott; Wendy S Barclay; Graham S Cooke; Helen Ward

doi:10.1093/cid/ciac629

Validity of Self-testing at Home With Rapid Severe Acute Respiratory Syndrome Coronavirus 2 Antibody Detection by Lateral Flow Immunoassay

Clin Infect Dis. 2023 Feb 18;76(4):658-666. doi: 10.1093/cid/ciac629.

Authors

Christina J Atchison^{1

2}, Maya Moshe³, Jonathan C Brown³, Matthew Whitaker¹, Nathan C K Wong⁴, Anil A Bharath⁴, Rachel A McKendry^{5

6}, Ara Darzi^{2

7}, Deborah Ashby¹, Christl A Donnelly^{1

8

9}, Steven Riley^{1

9}, Paul Elliott^{1

2

10

11

12

13}, Wendy S Barclay³, Graham S Cooke^{2

3

10}, Helen Ward^{1

2

9

10}

Affiliations

¹ School of Public Health, Imperial College London, London, United Kingdom.
² Imperial College Healthcare NHS Trust, London, United Kingdom.
³ Department of Infectious Disease, Imperial College London, London, United Kingdom.
⁴ Department of Bioengineering, Imperial College London, London, United Kingdom.
⁵ London Centre for Nanotechnology & Division of Medicine, University College London, London, United Kingdom.
⁶ Division of Medicine, University College London, London, United Kingdom.
⁷ Institute of Global Health Innovation at Imperial College London, London, United Kingdom.
⁸ Department of Statistics, University of Oxford, Oxford, United Kingdom.
⁹ MRC Centre for Global infectious Disease Analysis and Abdul Latif Jameel Institute for Disease and Emergency Analytics, Imperial College London, London, United Kingdom.
¹⁰ National Institute for Health Research Imperial Biomedical Research Centre, London, United Kingdom.
¹¹ MRC Centre for Environment and Health, School of Public Health, Imperial College London, London, United Kingdom.
¹² Health Data Research (HDR) UK London at Imperial College, London, United Kingdom.
¹³ UK Dementia Research Institute at Imperial College, London, United Kingdom.

Abstract

Background: We explore severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody lateral flow immunoassay (LFIA) performance under field conditions compared to laboratory-based electrochemiluminescence immunoassay (ECLIA) and live virus neutralization.

Methods: In July 2021, 3758 participants performed, at home, a self-administered Fortress LFIA on finger-prick blood, reported and submitted a photograph of the result, and provided a self-collected capillary blood sample for assessment of immunoglobulin G (IgG) antibodies using the Roche Elecsys® Anti-SARS-CoV-2 ECLIA. We compared the self-reported LFIA result to the quantitative ECLIA and checked the reading of the LFIA result with an automated image analysis (ALFA). In a subsample of 250 participants, we compared the results to live virus neutralization.

Results: Almost all participants (3593/3758, 95.6%) had been vaccinated or reported prior infection. Overall, 2777/3758 (73.9%) were positive on self-reported LFIA, 2811/3457 (81.3%) positive by LFIA when ALFA-reported, and 3622/3758 (96.4%) positive on ECLIA (using the manufacturer reference standard threshold for positivity of 0.8 U mL-1). Live virus neutralization was detected in 169 of 250 randomly selected samples (67.6%); 133/169 were positive with self-reported LFIA (sensitivity 78.7%; 95% confidence interval [CI]: 71.8, 84.6), 142/155 (91.6%; 95% CI: 86.1, 95.5) with ALFA, and 169 (100%; 95% CI: 97.8, 100.0) with ECLIA. There were 81 samples with no detectable virus neutralization; 47/81 were negative with self-reported LFIA (specificity 58.0%; 95% CI: 46.5, 68.9), 34/75 (45.3%; 95% CI: 33.8, 57.3) with ALFA, and 0/81 (0%; 95% CI: 0, 4.5) with ECLIA.

Conclusions: Self-administered LFIA is less sensitive than a quantitative antibody test, but the positivity in LFIA correlates better than the quantitative ECLIA with virus neutralization.

Keywords: COVID-19; SARS-CoV-2; antibodies; home-testing; lateral flow immunoassay.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Antibodies, Viral
COVID-19* / diagnosis
Humans
Immunoassay / methods
SARS-CoV-2*
Self-Testing
Sensitivity and Specificity

Substances

Antibodies, Viral

Abstract

Publication types

MeSH terms

Substances

Grants and funding