Evaluation of novel antigen-based rapid detection test for the diagnosis of SARS-CoV-2 in respiratory samples

Porte, Lorena; Legarraga, Paulette; Vollrath, Valeska; Aguilera, Ximena; Munita, José M.; Araos, Rafael; Pizarro, Gabriel; Vial, Pablo; Iruretagoyena, Mirentxu; Dittrich, Sabine; Weitzel, Thomas

OBJECTIVES: In the context of the Covid-19 pandemic, the development and validation of rapid and easy-to-perform diagnostic methods are of high priority. We evaluated a novel rapid antigen detection test (RDT) for SARS-CoV-2 in respiratory samples. METHODS: The fluorescence immunochromatographic SARS-CoV-2 antigen test (Bioeasy Biotechnology Co., Shenzhen, China) was evaluated using universal transport medium with nasopharyngeal (NP) and oropharyngeal (OP) swabs from suspected Covid-19 cases. Diagnostic accuracy was determined in comparison to SARS-CoV-2 real time (RT)-PCR. RESULTS: A total of 127 samples were included; 82 were RT-PCR positive. Median patients’ age was 38 years, 53.5% were male, and 93.7% were from the first week after symptom onset. Overall sensitivity and specificity were 93.9% (CI95% 86.5–97.4) and 100% (CI95% 92.1–100), respectively, with a diagnostic accuracy of 96.1% and Kappa coefficient of 0.9. Sensitivity was significantly higher in samples with high viral loads. CONCLUSIONS: The evaluated RDT showed a high sensitivity and specificity in samples mainly obtained during the first week of symptoms and with high viral loads, despite the use of a non-validated sample material. The assay has the potential to become an important tool for early diagnosis of SARS-CoV-2, particularly in situations with limited access to molecular methods.