Analytical performance of lateral flow immunoassay for SARS-CoV-2 exposure screening on venous and capillary blood samples

J Immunol Methods. 2021 Feb:489:112909. doi: 10.1016/j.jim.2020.112909. Epub 2020 Nov 7.

Abstract

Objectives: We validate the use of a lateral flow immunoassay (LFI) intended for rapid screening and qualitative detection of anti-SARS-CoV-2 IgM and IgG in serum, plasma, and whole blood, and compare results with ELISA. We also seek to establish the value of LFI testing on blood obtained from a capillary blood sample.

Methods: Samples collected by venous blood draw and finger stick were obtained from patients with SARS-CoV-2 detected by RT-qPCR and control patients. Samples were tested with Biolidics 2019-nCoV IgG/IgM Detection Kit lateral flow immunoassay, and antibody calls were compared with ELISA.

Results: Biolidics LFI showed clinical sensitivity of 92% with venous blood at 7 days after PCR diagnosis of SARS-CoV-2. Test specificity was 92% for IgM and 100% for IgG. There was no significant difference in detecting IgM and IgG with Biolidics LFI and ELISA at D0 and D7 (p = 1.00), except for detection of IgM at D7 (p = 0.04). Capillary blood of SARS-CoV-2 patients showed 93% sensitivity for antibody detection.

Conclusions: Clinical performance of Biolidics 2019-nCoV IgG/IgM Detection Kit is comparable to ELISA and was consistent across sample types. This provides an opportunity for decentralized rapid testing and may allow point-of-care and longitudinal self-testing for the presence of anti-SARS-CoV-2 antibodies.

Keywords: COVID-19; Lateral flow immunoassay; SARS-CoV-2; Serology; Validation.

MeSH terms

  • Antibodies, Viral / blood*
  • Antibodies, Viral / immunology*
  • COVID-19 / blood*
  • COVID-19 / genetics
  • COVID-19 / immunology*
  • Capillaries
  • Enzyme-Linked Immunosorbent Assay
  • Humans
  • Immunoglobulin G / blood
  • Immunoglobulin G / immunology
  • Immunoglobulin M / blood
  • Immunoglobulin M / immunology
  • Immunologic Tests / standards*
  • Retrospective Studies
  • SARS-CoV-2 / immunology*
  • SARS-CoV-2 / isolation & purification*
  • Sensitivity and Specificity
  • Veins

Substances

  • Antibodies, Viral
  • Immunoglobulin G
  • Immunoglobulin M