Purpose: To determine the utility, diagnostic accuracy, sensitivity, specificity, and negative predictive value of the laboratory based Covid-19 antigen detection test (Coris Bio- Concept, Gembloux, Belgium) for the diagnosis of SARS-CoV-2 in a tertiary care hospital among symptomatic and asymptomatic patients.
Methods: The nasopharyngeal swab samples were collected from the symptomatic patients and their contacts. The diagnostic accuracy of this antigen kit was determined in comparison to SARS-CoV-2 real-time reverse transcriptase (RT-PCR).
Results: A total of 825 patients fulfilling the inclusion criteria were included in the study; RT-PCR and antigen detection was performed simultaneously for 484 samples to determine the sensitivity and specificity of the test. The overall specificity and sensitivity was 99.32% and 71.96% respectively. Also, 3.7% of the asymptomatic patients who were negative by RAT were detected positive by RT-PCR.
Conclusion: This rapid antigen test (RAT) was sensitive in the symptomatic patients presenting during the initial phase of the illness. Since, majority of the SARS-CoV-2 patients are asymptomatic and considering the huge population, the testing strategy formulated by Indian Council of Medical Research (ICMR) at the national level was cost effective. Thus, Ag-RDTs could play a pivotal role in early diagnosis, policy making and surveillance of the SARS-CoV-2.
Keywords: Point-of-care; Rapid antigen detection; SARS-CoV-2.
Copyright © 2021 Indian Association of Medical Microbiologists. Published by Elsevier B.V. All rights reserved.