Diagnostic Performance Evaluation of Three COVID-19 Rapid
Immunochromatographic Test Kits on Clinical Samples Tested by rRT-PCR.
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.