Publication:

An Assessment of a Rapid SARS-CoV-2 Antigen Test in Bangladesh

Rapid antigen detection tests are point-of-care immunochromatographic assays that detect protein antigens specific to the SARS-CoV-2 (e.g., nucleocapsid).1 The ease of use and quick turnaround time of such tests can expand access to testing and decrease delays in diagnosis.2 Furthermore, modeling studies on SARS-CoV-2 have demonstrated that even if rapid antigen testing is associated with decreased sensitivity, the accessibility and short turnaround time in reporting results may be advantageous for decreasing transmission.3 Rapid antigen testing is particularly useful if deployed in the context of repeated testing over time.4,5 The performance of the rapid antigen tests has been determined by comparing their sensitivity and specificity with nucleic acid detection-based reference reaction.6 The current gold standard for identifying the presence of SARS-CoV-2 is reverse transcription polymerase chain reaction (RT-PCR) in samples collected by nasopharyngeal (NP) swab.7 Despite their high sensitivity, nucleic acid amplification tests are associated with the need for laboratory processing, high costs, and a longer turnaround from sampling to return of results.8,9 The NP swabs are also more challenging and uncomfortable (for patients) to collect than anterior nares swabs. For this reason, rapid antigen testing is a valuable tool for contact tracing and early detection of COVID-19 patients to triage for treatment options, especially in settings where RT-PCR is less available or where follow-up reporting of RT-PCR results is more difficult, and particularly when anterior nares samples can be used. In this study among asymptomatic and symptomatic adults, we evaluated the performance (sensitivity/specificity) of two rapid antigen detection tests, the BD Veritor (Becton-Dickenson, Franklin Lakes, NJ) and the Standard Q (SD-Biosensor, Gyeonggi-do, Korea) rapid antigen test, in comparison to NP swab RT-PCR as the reference standard. The BD Veritor was performed according to the manufacturer’s recommendations using an anterior nares swab specimen, and the Standard Q and reference RT-PCR were performed on NP swab specimens. We also evaluated the performance of the rapid antigen tests across the spectrum of RT-PCR cycle threshold (Ct) values. Finally, we assessed the implementation characteristics of the BD Veritor rapid antigen test, including fitness-for-use in different populations and settings in Bangladesh.