Diagnostic Accuracy of SARS-CoV-2 Rapid Antigen Test (Oral Fluid) with Unsupervised Self-sampling in the Omicron Period

*Corresondence to: Zhang Lei, Zhejiang Gongshang University, China
Received: Oct 14, 2022; Accepted: Oct 18, 2022; Published: Oct 20, 2022
Citation: Lei Z, Feng Y, Junzhe Z (2022) Diagnostic Accuracy of SARS-CoV-2 Rapid Antigen Test (Oral Fluid) with Unsupervised Self-sampling in the Omicron Period. Global Health Science Journal 2:110. DOI: https://doi.org/10.61309/ghs.1000110
Copyright: ©2021 Lei Z et.al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

ABSTRACT

Background: To assess the performance of rapid antigen tests between unsupervised oral fluid self-sampling and nasal self-sampling during the omicron period. Objective: To diagnostically validate SARS-CoV-2 Rapid Antigen Test (Oral Fluid) by comparing results with those of nasal self-sampling in the omicron period. Method: Run rapid in vitro diagnostic tests for detection of antigen to SARS-CoV-2 in nasal and oral fluid sampling, compared to a leading commercial test using clinical specimens for validation of performance. Result: When nasal self-sampling compared with nasal self-sampling, sensitivities were found to be slightly higher in confirmatory testers. Sensitivity (94.3%): In total 297 PCR in the Clinitest group were confirmatory testers (previously tested positive by a self-test at own initiative), 280 PCR confirmed positive samples were correctly detected by SARS-CoV-2 (COVID-19) Rapid Test (Oral Fluid). 17 false negative cases were reported. Specificity (99.4%): In total 350 PCR confirmed negative samples were correctly detected by SARS-CoV-2 (COVID-19) Rapid Test (Oral Fluid). Only 2 false positive cases were reported.Accuracy (97.1%): In total 649 PCR confirmed samples: 630 PCR confirmed samples were correctly detected by SARS-CoV-2 (COVID-19) Rapid Test (Oral Fluid). Among which, overall sensitivities with nasal self-sampling were 79.0% (95% confidence interval 74.7% to 82.8%) for SARS-CoV-2 by Rapid Antigen Tests on Saliva. Sensitivities were substantially higher in confirmatory testers with Citest SARS-CoV-2 Rapid Antigen Test (Oral Fluid) than in those who tested for other reasons.Conclusion: Sensitivities of three rapid antigen tests with nasal self-sampling decreased during the emergence of omicron but was only statistically significant for Clinitest. Sensitivities appeared to be substantially influenced by the proportion of confirmatory testers. Sensitivities of Citest SARS-CoV-2 Rapid Antigen Test improved after the addition of Oral Fluid self-sampling. A positive self-test result justifies prompt self-isolation without the need for confirmatory testing. Individuals with a negative self-test result should adhere to general preventive measures because a false negative result cannot be ruled out.

Keyword: Rapid Antigen Test; Oral Fluid; Self-sampling; Omicron Period