FIND evaluations of SARS-CoV-2 Ab tests

SARS-CoV-2-specific antibodies (Ab) are part of the immune response to infection, and may be detected during the early, late, convalescent, and post-recovery phases of disease. They are most useful for identifying recent or prior infection.

In March 2020, FIND launched an expression of interest (EOI) process for test developers interested in having their immunoassays for the detection of SARS-CoV-2 antibodies evaluated using standardized, independent protocols. Thirty-five RDTs and 16 manual ELISA tests were selected for inclusion in the studies.

In collaboration with partners, FIND conducted multicentre diagnostic evaluation studies from Q2 2020-Q1 2021 of the selected COVID-19 antibody assays using archived, frozen serum/plasma. In addition to clinical samples, we also performed a limited cross-reactivity assessment for the RDTs using samples from individuals confirmed to have had malaria/and or dengue infection. Finally, all tests (RDTs and ELISAs) were tested using a working reference panel developed by the National Institute for Biological Standards and Control (NIBSC). All evaluations are now complete, and results are available.

Results for the evaluation of 35 Antibody RDTs:

• The clinical performance estimates for the 35 RDTs which were evaluated can be accessed here.
• The limited cross-reactivity assessment for the RDTs can be accessed here.

Results for the evaluation of 16 Antibody ELISAs

• The overall sensitivity and specificity estimates can be accessed here.
• A sub-analysis on the performance of manual ELISAs according to days post symptom onset can be found here.

Reactivity of all assays evaluated (RDTs + ELISA) according to the NIBSC panels can be found here.

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Last updated 30 April 2021

More information

For questions relating to the evaluation of immunoassays, please contact our Emerging Threats team.