Diagnostic accuracy of PanbioTM rapid antigen tests on oropharyngeal swabs for detection of SARS-CoV-2 (preprint)

ABSTRACT

Background Antigen-detecting rapid diagnostic tests (Ag-RDTs) for the detection of SARS-CoV-2 offer new opportunities for testing in the context of the COVID-19 pandemic. Nasopharyngeal swabs (NPS) are the reference sample type, but oropharyngeal swabs (OPS) may be a more acceptable sample type in some patients. Methods We conducted a prospective study in a single screening center to assess the diagnostic performance of the PanbioTM COVID-19 Ag Rapid Test (Abbott) on OPS compared with reverse-transcription quantitative PCR (RT-qPCR) using NPS. Results 402 outpatients were enrolled in a COVID-19 screening center, of whom 168 (41.8%) had a positive RT-qPCR test. The oropharyngeal Ag-RDT sensitivity compared to nasopharyngeal RT-qPCR was 81% (95%CI 74.2-86.6). Two false positives were noted out of the 234 RT-qPCR negative individuals, which resulted in a specificity of 99.1% (95%CI 96.9-99.9) for the RDT. For cycle threshold values [≤] 26.7 ([≥] 1E6 SARS-CoV-2 genomes copies/mL, a presumed cut-off for infectious virus), 96.3% sensitivity (95%CI 90.7-99.0%) was obtained with the Ag-RDT using OPS. Interpretation Based on our findings, the diagnostic performance of the PanbioTM Covid-19 RDT with OPS samples meet the criteria required by the WHO for Ag-RDTs (sensitivity [≥] 80% and specificity [≥] 97%).