Efficient testing strategies are key for diagnosis, clinical management, and outbreak control of SARS-CoV-2/COVID-19

2 September 2022

A recent CAPRISA-led study evaluated the performance of SARS-CoV-2 rapid antigen tests in South Africa during the Omicron wave. The study titled, Clinical Evaluation of Severe Acute Respiratory Syndrome Coronavirus 2 Rapid Antigen Tests During the Omicron Wave in South Africa, published in the Journal of Infectious Diseases report on the performance of nasal and nasopharyngeal Standard Q COVID-19 Ag tests (SD Biosensor) and the Panbio COVID-19 Ag Rapid Test Device (nasal, Abbott) against the Abbott RealTime SARS-CoV-2 assay during the Omicron (21M, 21K and 21L) wave in South Africa.

The study led by Director of CAPRISA Laboratories Ms Natasha Samsunder and Senior Scientist Dr Aida Sivro, in collaboration with Foundation for Innovative New diagnostics (FIND) showed that overall, all evaluated tests performed well with high level of sensitivity (ranging from 77.78-81.42%) and excellent specificity values (>99%). 

The sensitivity of rapid antigen tests increased above 90% in samples with CT <20, and all three tests performed best within first week of symptom onset. The Panbio Ag test performed best in the context of Omicron 21L infections, that were also characterised by significantly lower CT values compared to infections with 21K and 21M.  Overall, the data indicates that the tested SD Biosensor and Panbio rapid SARS-CoV-2/COVID-19 antigen 

For more reading see: Samsunder N, et al. Journal of Infectious Diseases. 2022. https://doi.org/10.1093/infdis/jiac333