ABSTRACT
Background : COVID-19 has imposed significant burden on
healthcare systems worldwide. The need for simple, rapid, and affordable
diagnostic tests to support the existing costly and demanding polymerase
chain reaction (PCR) assay is very necessary.
Methods: This study evaluated the performance characteristics
of three (3) COVID-19 rapid antigen test kits: DG Rapid, SD Rapid and SS
Rapid. They were compared with the gold standard real-time reverse
transcriptase- PCR (rRT-PCR) for the detection of SARS-CoV-2
nucleocapsid antigen in 75 archived samples.
Results: Of the 75 samples tested, 38 (50.7%) were positive
and 37 (49.3%) were negative for SARS-CoV-2 RNA by rRT-PCR assay. No
false positive was recorded. The DG Rapid kit detected 30 (78.9%) true
positives and 8 (21.1%) false negatives. SD Rapid kit detected 28
(73.7%) true positives and 10 (26.3%) false negatives, while the SS
Rapid kit detected 19 (50.0%) true positives and 19 (50.0%) false
negatives. Specificity of each test kit was 100% (CI 95%), but the
sensitivity of the DG Rapid, SD Rapid, and SS Rapid kits was 79%, 74%,
and 50% (CI 95%), respectively. Higher sensitivities among samples
with Ct values <29.99 were recorded for each kit. Also, the DG
Rapid kit demonstrated 79% excellent agreement with rRT-PCR, while the
SD Rapid and SS Rapid kits demonstrated good agreement with rRT-PCR with
73% and 50% Cohen’s kappa values, respectively.
Conclusion: The study suggests that DG Rapid and SD Rapid kits
are reliable alternatives to rRT-PCR for the detection of SARS-CoV-2
infection, especially in resource-limited settings like Ghana.
Keywords: COVID-19, SARS-CoV-2, polymerase chain reaction
(PCR), rapid antigen test kits.