Detection of SARS-CoV-2 Omicron, Delta, Alpha and Gamma variants using a rapid antigen test

Throughout the coronavirus disease 2019 (COVID-19) pandemic, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants have emerged with different infection and disease dynamics. Testing strategies, including clinical diagnosis, surveillance, and screening, have been deployed to help limit the spread of SARS-CoV-2 variants. Rapid antigen tests, in particular, have been approved for self-testing in many countries and governments are supporting their manufacturing and distribution. However, studies demonstrating the accuracy of rapid antigen tests in detecting SARS-CoV-2 variants, especially the new Omicron variant, are limited. We determined the analytical sensitivity of a CE-marked rapid antigen test against the Omicron, Delta, Alpha and Gamma variants. The rapid antigen test had the most sensitive limit of detection (10 plaque forming units [PFU]/mL) when tested with the Alpha and Gamma variants, followed by the Omicron (100 PFU/mL) and Delta (1,000 PFU/mL) variants. Given the increasing numbers of breakthrough infections and the need to surveil infectiousness, rapid antigen tests are effective public health tools to detect SARS-CoV-2 variants.