Evaluation of 11 SARS-CoV-2 antibody tests by using samples from patients with defined IgG antibody titers

Sci Rep. 2021 Apr 7;11(1):7614. doi: 10.1038/s41598-021-87289-6.

Abstract

We evaluated the performance of 11 SARS-CoV-2 antibody tests using a reference set of heat-inactivated samples from 278 unexposed persons and 258 COVID-19 patients, some of whom contributed serial samples. The reference set included samples with a variation in SARS-CoV-2 IgG antibody titers, as determined by an in-house immunofluorescence assay (IFA). The five evaluated rapid diagnostic tests had a specificity of 99.0% and a sensitivity that ranged from 56.3 to 81.6% and decreased with low IFA IgG titers. The specificity was > 99% for five out of six platform-based tests, and when assessed using samples collected ≥ 22 days after symptom onset, two assays had a sensitivity of > 96%. These two assays also detected samples with low IFA titers more frequently than the other assays. In conclusion, the evaluated antibody tests showed a heterogeneity in their performances and only a few tests performed well with samples having low IFA IgG titers, an important aspect for diagnostics and epidemiological investigations.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Antibodies, Viral / blood
  • Antibodies, Viral / immunology
  • COVID-19 / blood
  • COVID-19 / diagnosis*
  • COVID-19 / immunology
  • COVID-19 Serological Testing / economics
  • COVID-19 Serological Testing / methods*
  • Child
  • Child, Preschool
  • Female
  • Humans
  • Immunoglobulin G / blood
  • Immunoglobulin G / immunology
  • Male
  • Middle Aged
  • SARS-CoV-2 / immunology
  • SARS-CoV-2 / isolation & purification*
  • Sensitivity and Specificity
  • Time Factors
  • Young Adult

Substances

  • Antibodies, Viral
  • Immunoglobulin G