Limited specificity of commercially available SARS‐CoV‐2 IgG ELISAs in serum samples of African origin

  1. Petra Emmerich
  2. Carolin Murawski
  3. Christa Ehmen
  4. Ronald von Possel
  5. Neele Pekarek
  6. Lisa Oestereich
  7. Sophie Duraffour
  8. Meike Pahlmann
  9. Nicole Struck
  10. Daniel Eibach
  11. Ralf Krumkamp
  12. John Amuasi
  13. Oumou Maiga‐Ascofaré
  14. Raphael Rakotozandrindrainy
  15. Danny Asogun
  16. Yemisi Ighodalo
  17. Simone Kann
  18. Jürgen May
  19. Egbert Tannich
  20. Christina Deschermeier

Reviewed by

Read the full article See related articles

Discuss this preprint

Start a discussion What are Sciety discussions?

Listed in

Log in to save this article

Abstract

Objectives

Specific serological tests are mandatory for reliable SARS‐CoV‐2 diagnostics and seroprevalence studies. Here, we assess the specificities of four commercially available SARS‐CoV‐2 IgG ELISAs in serum/plasma panels originating from Africa, South America, and Europe.

Methods

882 serum/plasma samples collected from symptom‐free donors before the COVID‐19 pandemic in three African countries (Ghana, Madagascar, Nigeria), Colombia, and Germany were analysed with three nucleocapsid‐based ELISAs (Euroimmun Anti‐SARS‐CoV‐2‐NCP IgG, EDI™ Novel Coronavirus COVID‐19 IgG, Mikrogen recom Well SARS‐CoV‐2 IgG), one spike/S1‐based ELISA (Euroimmun Anti‐SARS‐CoV‐2 IgG), and in‐house common cold CoV ELISAs.

Results

High specificity was confirmed for all SARS‐CoV‐2 IgG ELISAs for Madagascan (93.4–99.4%), Colombian (97.8–100.0%), and German (95.9–100.0%) samples. In contrast, specificity was much lower for the Ghanaian and Nigerian serum panels (Ghana: NCP‐based assays 77.7–89.7%, spike/S1‐based assay 94.3%; Nigeria: NCP‐based assays 39.3–82.7%, spike/S1‐based assay 90.7%). 15 of 600 African sera were concordantly classified as positive in both the NCP‐based and the spike/S1‐based Euroimmun ELISA, but did not inhibit spike/ACE2 binding in a surrogate virus neutralisation test. IgG antibodies elicited by previous infections with common cold CoVs were found in all sample panels, including those from Madagascar, Colombia, and Germany and thus do not inevitably hamper assay specificity. Nevertheless, high levels of IgG antibodies interacting with OC43 NCP were found in all 15 SARS‐CoV‐2 NCP/spike/S1 ELISA positive sera.

Conclusions

Depending on the chosen antigen and assay protocol, SARS‐CoV‐2 IgG ELISA specificity may be significantly reduced in certain populations probably due to interference of immune responses to endemic pathogens like other viruses or parasites.

Article activity feed

  1. Version published to 10.1111/tmi.13569
  2. ScreenIT

    SciScore for 10.1101/2020.09.15.20159749: (What is this?)

    Please note, not all rigor criteria are appropriate for all manuscripts.

    Table 1: Rigor

    Institutional Review Board Statementnot detected.
    Randomizationnot detected.
    Blindingnot detected.
    Power Analysisnot detected.
    Sex as a biological variablenot detected.

    Table 2: Resources

    No key resources detected.

    Results from OddPub: We did not detect open data. We also did not detect open code. Researchers are encouraged to share open data when possible (see Nature blog).

    Results from LimitationRecognizer: An explicit section about the limitations of the techniques employed in this study was not found. We encourage authors to address study limitations.

    Results from TrialIdentifier: No clinical trial numbers were referenced.

    Results from Barzooka: We did not find any issues relating to the usage of bar graphs.

    Results from JetFighter: We did not find any issues relating to colormaps.

    Results from rtransparent:
    • Thank you for including a conflict of interest statement. Authors are encouraged to include this statement when submitting to a journal.
    • Thank you for including a funding statement. Authors are encouraged to include this statement when submitting to a journal.
    • No protocol registration statement was detected.

    About SciScore

    SciScore is an automated tool that is designed to assist expert reviewers by finding and presenting formulaic information scattered throughout a paper in a standard, easy to digest format. SciScore checks for the presence and correctness of RRIDs (research resource identifiers), and for rigor criteria such as sex and investigator blinding. For details on the theoretical underpinning of rigor criteria and the tools shown here, including references cited, please follow this link.

  3. Version published to 10.1101/2020.09.15.20159749 on medRxiv