FIND evaluation of SARS-CoV-2 antigen (Ag) detecting tests

SARS-CoV-2 antigens are shed as the virus replicates during active infection, and thus their detection can be used to diagnose current infection.

FIND is conducting prospective diagnostic evaluation studies in collaboration with multiple independent sites to determine the accuracy of COVID-19 Ag RDTs. We are currently busy evaluating assays that have already been selected (Table 1) and are selecting new tests to be evaluated by end of 2021. The expression of interest (EOI) to participate in the Ag RDT evaluations is now closed and may reopen at the end of 2021.

Antigen RDT evaluation protocol summary

Results for ongoing evaluations will continue to be updated on a routine basis (Table 1). Last update: 8 July 2021

Note: Lower test sensitivity has been observed repeatedly in the evaluations performed in the study sites in India. A root-cause analysis exercise, which included sampling and testing parameters, has been conducted and did not return a conclusive cause for this lower performance compared to results obtained at other study sites. It must be noted that all the referenced evaluations were conducted prior to the emergence of the newly detected variants in India, such as B.1.617. A remaining hypothesis, which has not been confirmed, is that the higher temperature and humidity conditions observed in India may be contributing to varied performance.

More information

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