· Studies suggest that antigen-based rapid diagnostic tests (Ag-RDTs) can be used in a population level with high prevalence of COVID-19 disease where health systems are overwhelmed or where nucleic acid amplification tests (NAATs) such as real time reverse transcription polymerase chain reaction (rRT-PCR) are not available.
· The Canadian COVID-19 Testing and Screening Expert Advisory Panel recommends the use of frequent screening with rapid diagnostic tests in selected groups to limit outbreaks.
· WHO and European Center for Disease Prevention and Control recommend using Ag-RDTs with high sensitivity and specificity when NAATs are not available or turnaround time negatively affects NAATs’ clinical utility. For example, COVID-19 Ag-RDTs can be used to surveil health care workers or residents of congregate dwellings during outbreaks or when community transmission rates are high, to screen at-risk individuals to support outbreak investigations, or to screen suspected COVID-19 outbreaks in early stages in settings where NAATs are not available.
· WHO does not recommend Ag-RDTs usage when expected prevalence is low (e.g., screening at points of entry) unless an Ag-RDT’s specificity is high (>99%).
· Studies have shown that Panbio™ COVID-19 Ag Test (Abbott) can have overall sensitivity of 72.6% to 95.2% and specificity of 98.0% to 100% and suggest that this test is appropriate for contagious case identification and asymptomatic case screening, especially in high prevalence (>5%) settings.
· WHO recommends that iterative Ag-RDT testing or confirmatory rRT-PCR testing be done in symptomatic patients or asymptomatic contacts of COVID-19 cases since a negative Ag-RDT result cannot completely exclude an active COVID-19 infection.
· Challenges of population level testing (whether they succeed or fail) such as required logistics and resources (e.g., immunizers, access to Ag-RDTs and equipment), performance accuracy of Ag-RDTs (e.g., false positive or negative rates in real world settings), and public trust and engagement in testing and future measures (e.g., vaccine uptake) are yet to be considered.