Accuracy and ease-of-use of seven point-of-care SARS-CoV-2 antigen-detecting tests: A multi-centre clinical evaluation

Abstract

Background Antigen-detecting rapid diagnostic tests (Ag-RDTs) for SARS-CoV-2 are important diagnostic tools. We assessed clinical performance and ease-of-use of seven Ag-RDTs in a prospective, manufacturer-independent, multi-centre cross-sectional diagnostic accuracy study to inform global decision makers. Methods Unvaccinated participants suspected of a first SARS-CoV-2 infection were recruited at six sites (Germany, Brazil). Ag-RDTs were evaluated sequentially, with collection of paired swabs for routine reverse transcription polymerase chain reaction (RT-PCR) testing and Ag-RDT testing. Performance was compared to RT-PCR overall and in sub-group analyses (viral load, symptoms, symptoms duration). To understandusability a System Usability Scale (SUS) questionnaire and ease-of-use (EoU) assessment were performed. Findings 7471 participants were included in the analysis. Sensitivities across Ag-RDTs ranged from 70·4%-90·1%, specificities were above 97·2% for all Ag-RDTs but one (93·1%).Ag-RDTs, Mologic, Bionote, Standard Q, showed diagnostic accuracy in line with WHO targets (> 80% sensitivity, > 97% specificity). All tests showed high sensitivity in the first three days after symptom onset (≥87·1%) and in individuals with viral loads≥ 6 log 10 SARS-CoV2 RNA copies/mL (≥ 88·7%). Usability varied, with Rapigen, Bionote and Standard Q reaching very good scores; 90, 88 and 84/100, respectively. Interpretation Variability in test performance is partially explained by variable viral loads in population evaluated over the course of the pandemic. All Ag-RDTs reach high sensitivity early in the disease and in individuals with high viral loads, supporting their role in identifying transmission relevant infections. For easy-to-use tests, performance shown will likely be maintained in routine implementation. Funding Ministry of Science, Research and Arts, State of Baden-Wuerttemberg, Germany, internal funds from Heidelberg University Hospital, University Hospital Charité − Universitätsmedizin Berlin, UK Department of International Development, WHO, Unitaid.

Evaluation of pre-hospital COVID-19 rapid antigen tests by paramedics and their use in a direct admission pathway

“…PRACTICAL 1: Pre-hospital LFD was performed in 50 patients, with 32 having COVID-19 PCR as part of the assessment on arrival into hospital. Compared with PCR, sensitivity was 77.8% and specificity was 100% ( Table 1 ), in keeping with previously reported test performance 6 .…”

“…In the Hull and East Yorkshire region, ambulance crews had increased waiting times to handover patients to Accident and Emergency, and oxygen capacity in the main admitting hospital was stretched to capacity. In response to these pressures, we established two complementary projects: PRACTICAL (Pre-hospital RApid COVID-19 Testing for Improved CAre in HulL) 1: A performance assessment of a lateral flow rapid antigen test for COVID-19 (COVIOS Ag Covid-19 rapid antigen test; legal manufacturer Mologic UK) 6 performed by ambulance paramedics attending to patients; and PRACTICAL 2: A direct admission pathway separate from Accident and Emergency for patients with a positive COVID-19 test within 14 days (including same-day LFD by paramedic).…”

Impaired detection of omicron by SARS-CoV-2 rapid antigen tests

“…In many countries, rapid antigen tests (RATs) for the detection of SARS-CoV-2 continue to be a central component of national testing strategies offering quick, inexpensive and laboratory-independent, point-of-care diagnostics. However, the evaluation by independent laboratories [14][15][16][17][18][19][20][21][22][23][24][25] and a Cochrane meta-analysis [26] have indicated a highly variable performance of RATs resulting in an ongoing controversy over these tests' utility for the detection of acute SARS-CoV-2-infected individuals in different settings relevant for clinical diagnosis and containment strategies.…”

Performance differences among commercially available antigen rapid tests for COVID-19 in Brazil

“…Several Ag-RDTs have been developed by various manufacturers from multiple countries and have been evaluated independently by researchers. However, most validation studies have evaluated the same tests mainly in Europe [ 16 – 18 ], highlighting the need for studies in countries where they are commercialized, because the population characteristics and different circulating virus variants may affect their performance [ 19 ]. Here, we evaluated the performance of eight Ag-RDTs for COVID-19 currently available in Brazil in hospitalized patients with moderate or mild disease and risk factors for severe disease requiring close monitoring.…”