Comprehensive, comparative evaluation of 25 automated SARS-CoV-2 serology assays

Abstract

We have previously highlighted the fact that hundreds of SARS-CoV-2 serology tests were released months after the onset of the COVID-19 pandemic. Of the hundreds of studies investigating the test kits' performance, few were comparative reports, using the same comprehensive sample set across multiple tests. Recently, we reported a comparative assessment of 35 rapid diagnostic tests (RDTs) or microtiter plate enzyme immunoassays (EIA) for use in low- and middle-income countries, using a large sample set from individuals with a history of COVID-19. Only a few tests meet WHO Target Product Profile performance requirements. This study reports on the performance of a further 25 automated SARS-CoV-2 immunoassays using the same panel of samples. The results highlight the better analytical and clinical performance of automated serology test kits compared with RDTs, and the importance of independent comparative assessments to inform the use and procurement of these tests for both diagnostic and epidemiological investigations.

Keywords: anti-SARS-CoV-2 antibodies; automated assays; evaluation; serology.

Fig 1

Concordances with recent infection (n = 199), and specificities (n = 300) of automated SARS-CoV-2 serology testing for either IgG or Total antibodies. Concordance and specificity results are presented as a heat map, with shades of green representing results of >90%, and shades of yellow representing results of between 60% and 90%.

Fig 2

Results of testing two lots (A and B) of automated SARS-CoV-2 IgG or Total antibody test kits on three serial dilutions of antibody-positive samples, with R indicating reactive results and NR indicating non-reactive results.