Clinical assessment of SARS-CoV-2 antigen rapid detection compared with RT-PCR assay for emerging variants at a high-throughput community testing site in Taiwan

Objectives: With the emergence of the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) B.1.1.7 lineage in the ongoing coronavirus disease 2019 (COVID-19) pandemic, Taiwan confronted a COVID19 flare up in May 2021. Large-scale, accurate, affordable and rapid diagnostic tests such as the lateral flow assay can help to prevent community transmission, but their performance characteristics in realworld conditions and relevant subpopulations remain unclear. Methods: The COVID-19 Antigen Rapid Test Kit (Eternal Materials, New Taipei City, Taiwan) was used in a high-throughput community testing site; the paired reverse transcription polymerase chain reaction (RT-PCR) results served as a reference for sensitivity and specificity calculations. Results: Of 2096 specimens tested using the rapid antigen test, 70 (3.33%) were positive and 2026 (96.7%) were negative. This clinical performance was compared with the RT-PCR results. The sensitivity and specificity of the rapid antigen test were 76.39% [95% confidence interval (CI) 64.91-85.60%] and 99.26% (95% CI 98.78-99.58%), respectively, with high sensitivity in subjects with cycle threshold values <= 24. Further, the rapid antigen test detected the SARS-CoV-2 B.1.1.7 lineage effectively. Conclusions: Considering the short turnaround times and lower costs, this simple SARS-CoV-2 antigen detection test for rapid screening combined with RT-PCR as a double confirmatory screening tool can facilitate the prevention of community transmission during COVID-19 emergencies. (C) 2021 The Author(s). Published by Elsevier Ltd on behalf of International Society for Infectious Diseases.

Automated summary

This study evaluated the performance of the COVID-19 antigen rapid test kit in a community testing site. The results showed high sensitivity and specificity of the test, especially in subjects with cycle threshold values <= 24. The test also effectively detected the SARS-CoV-2 B.1.1.7 lineage.