Evaluation of diagnostic performance of SARS-CoV-2 detection kits: a comparative study

Coronavirus Disease 2019 (COVID-19) pandemic has hit many countries worldwide. Rapid and accurate diagnosis is crucial to reduce disease burden. Many commercial kits have become available, but their performance needs to be assessed. This study aimed at evaluation of the diagnostic performance of real-time polymerase chain reaction (RT-PCR) and Rapid Antigen detection (RAD) kits for detecting Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). Five hundred sixty-four Nasopharyngeal swab specimens sent to Molecular Laboratory at Ain Shams University Specialized Hospital for SARS-CoV-2 PCR testing collected from 564 subjects who attended the outpatient clinic for sample collection were randomly selected. All samples were tested for SARS-CoV-2 PCR using Viasure. Each time a recent kit was introduced, 94 samples, previously tested using Viasure, were used to determine the performance characteristics of the recent kit in comparison with Viasure, including Fast Track Diagnostics (FTD), DNA Technology, QiaPrep, Xpress SARS-CoV-2, ID NOW COVID-19 assay and Artron COVID-19 Antigen test kit.

Upon comparison, FTD, DNA Technology, QiaPrep, Xpress SARS-CoV-2 and ID Now showed positive percent agreement, 100%, 100%, 97.7%, 100%, 100% negative percent agreement, 86%, 100%, 98.8%, 90%, 100%, respectively. The RAD kit results, when compared with RT-PCR, showed high sensitivity at cycle threshold (Ct) < 30, low sensitivity at Ct ≥ 30, while specificity was 100%.

Fast track, DNA Technology, QiaPrep, Xpress SARS-CoV-2 and ID Now showed good diagnostic performance. Positive RAD rule in SARS-CoV-2 infection, however negative results should be correlated with clinical condition and molecular testing.