Abstract
Accessible and timely diagnostic testing was essential during the COVID-19 pandemic to control the virus's spread and mitigate severe outcomes. However, real-time polymerase chain reaction tests, although sensitive incur high costs and prolonged turnaround times, and face implementation challenges in many resource-constrained settings. Antigen rapid diagnostic tests (Ag-RDT), which can be administered either by providers or as self-tests, are accessible and low-cost alternatives. We conducted this study to assess the acceptability of Ag-RDT in different use cases and delivery models in Malawi, Nigeria, and Zimbabwe. We implemented a qualitative study drawing on Louart's theoretical framework for the acceptability of technological healthcare innovations. In-depth interviews (n = 228) were conducted with community members, healthcare workers and providers to explore participants' experiences with Ag-RDT COVID-19 testing. Data were analysed using NVivo 14 software, applying an inductive thematic approach centred on the constant comparison method across countries, participant groups, and delivery models. The study revealed that Ag-RDT COVID-19 testing was acceptable across the three settings due to speed, non-invasiveness, and simplicity in sample collection compared to the real-time polymerase chain reaction alternative. Ag-RDT was integrated into existing healthcare systems with minimal disruption and used effectively across different use cases and populations. Participants particularly valued the self-testing option for its privacy, reduced stigma and convenience. However, acceptability was somewhat affected by the timing of the intervention, as it was implemented toward the end of the COVID-19 pandemic when many individuals no longer perceived testing as a priority. COVID-19 Ag-RDT testing was an acceptable complementary methodology to PCR testing in Malawi, Nigeria and Zimbabwe. The findings emphasise the need for strategic investment in accessible diagnostic technologies that complement existing molecular diagnostics, particularly supporting decentralised testing and rapid response capabilities in resource-constrained settings while maintaining robust surveillance systems.