Head-to-head comparison of four antigen-based rapid detection tests for the diagnosis of SARS-CoV-2 in respiratory samples

Abstract

21In the context of the Covid-19 pandemic, the development and validation of rapid and easy-to-22 perform diagnostic methods are of high priority. We compared the performance of four rapid 23 antigen detection tests for SARS-CoV-2 in respiratory samples. Immunochromatographic SARS-24CoV-2 assays from RapiGEN, Liming bio, Savant, and Bioeasy were evaluated using universal 25 transport medium containing naso-oropharyngeal swabs from suspected Covid-19 cases. The 26 diagnostic accuracy was determined in comparison to SARS-CoV-2 RT-PCR. A total of 111 27 samples were included; 80 were RT-PCR positive. Median patients' age was 40 years, 55% were 28 female, and 88% presented within the first week after symptom onset. The evaluation of the 29Liming bio assay was discontinued due to insufficient performance. The overall sensitivity 30 values of RapiGEN, Liming bio, and Bioeasy tests were 62.0% (CI95% 51.0-71.9), 16.7% 31 (CI95% 10.0-26.5), and 85.0% (CI95% 75.6-91.2), respectively, with specificities of 100%. 32Sensitivity was significantly higher in samples with high viral loads (RapiGEN, 84.9%; Bioeasy, 33 100%). The study highlighted the significant heterogeneity of test performance among evaluated 34 assays, which might have been influenced by the use of a non-validated sample material. The 35 high sensitivity of some tests demonstrated that rapid antigen detection has the potential to serve 36 as an alternative diagnostic method, especially in patients presenting with high viral loads in 37 early phases of infection. This is particularly important in situations with limited access to PCR or prolonged turnaround time. Further comparative evaluations are necessary to select 39 products with high performance among the growing market of diagnostic tests for SARS-CoV-2. 40 41

Rapid SARS-CoV-2 antigen detection by immunofluorescence – a new tool to detect infectivity

“…The copyright holder for this preprint this version posted October 6, 2020. ; https://doi.org/10.1101/2020.10.04.20206466 doi: medRxiv preprint 6 with automated reading (BioEasy), which demonstrated sensitivities of 100% for samples with Cts ≤ [6,7] and of 98% for samples with Cts ≤ [21]. In contrast, immunochromatographic SARS-CoV-2 antigen tests demonstrated lower sensitivity values of 74%-85% for samples with Cts ≤ 25 [7,22,23].…”

Laboratory diagnosis of coronavirus disease-2019 (COVID-19)

“…Immunochromatographic assay is the most commonly used method for the detection of SARS-CoV-2 antigens [74,75]. Thomas et al compared four lateral flow antigen-detection kits (RapiGEN, Liming bio, Savant, and Bioeasy) for the detection of SARS-CoV-2 and showed test performances with significant differences.…”

“…Among these tests, the Bioeasy test showed the highest accuracy of 89.2% and Kappa coefficient of 0.8, while Liming bio test was discontinued during testing because of poor performance. Sensitivities of other kits ranged from 16.7% for the Savant assay to 85% for the Bioeasy test [75].…”

SARS-CoV-2 pandemic: a review of molecular diagnostic tools including sample collection and commercial response with associated advantages and limitations

“…Such challenges have affected the clinical sensitivity of antigen tests for influenza and other respiratory viruses [112]. Recent studies on four different commercial antigen tests demonstrated a wide range of sensitivities from 16.7 to 85% (with 100% specificity) in COVID-19 clinical samples [113]. Other studies have shown sensitivity as high as 93.9% (CI 95%: 86.5-97.4).…”