Evaluation of the diagnostic performance of PanbioTM Abbott SARS-CoV-2 rapid antigen test for the detection of COVID-19 from suspects attending ALERT center

Correction: Evaluation of the diagnostic performance of PanbioTM Abbott SARS-CoV-2 rapid antigen test for the detection of COVID-19 from suspects attending ALERT center

[This corrects the article DOI: 10.1371/journal.pone.0277779.].

An Evaluation of the Sensitivity and Specificity of Three COVID-19 Rapid Immunochromatographic Test Kits Compared to Real-Time Reverse Transcriptase-Polymerase Chain Reaction (rRT-PCR) Among Clinical Samples

Background and objective The coronavirus disease 2019 (COVID-19) pandemic has imposed a significant burden on healthcare systems worldwide. This highlights the need for simple, rapid, and affordable diagnostic tests that can serve as alternatives to the existing costly and demanding polymerase chain reaction (PCR) assay, especially in resource-limited countries like Ghana. In light of this, we aimed to assess the diagnostic efficacy of three COVID-19 rapid immunochromatographic antigen test kits vs. real-time reverse transcriptase-PCR (rRT-PCR). Methods This study evaluated the sensitivity and specificity of three COVID-19 rapid immunochromatographic antigen test kits: DG Rapid, SD Rapid, and SS Rapid. They were compared with the gold standard RT-PCR for the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleocapsid antigen in 75 randomly selected archived nasopharyngeal samples. Results Of the 75 samples tested, 38 (50.7%) were positive and 37 (49.3%) were negative for SARS-CoV-2 RNA by rRT-PCR assay. No false positives were recorded. On the other hand, the DG Rapid kit detected 30 (78.9%) true positives and eight (21.1%) false negatives. SD Rapid kit detected 28 (73.7%) true positives and 10 (26.3%) false negatives, while the SS Rapid kit detected 19 (50.0%) true positives and 19 (50.0%) false negatives. While the specificity of each test kit was 100% (95% CI), the sensitivity of the DG Rapid, SD Rapid, and SS Rapid kits was 79%, 74%, and 50% (95% CI), respectively. Higher sensitivities were recorded among samples with cycle threshold (Ct) values <29.99 for each kit. Also, the DG Rapid kit demonstrated 79% excellent agreement with rRT-PCR, while the SD Rapid and SS Rapid kits demonstrated good agreement with rRT-PCR with 73% and 50% Cohen's kappa values, respectively. Conclusions Based on our findings, DG Rapid and SD Rapid kits are reliable alternatives to rRT-PCR for the detection of SARS-CoV-2 infection, especially in resource-limited settings like Ghana.

SARS-CoV-2 recombinase polymerase amplification assay with lateral flow readout and duplexed full process internal control

Nucleic acid amplification tests for the detection of SARS-CoV-2 have been an important testing mechanism for the COVID-19 pandemic. While these traditional nucleic acid diagnostic methods are highly sensitive and selective, they are not suited to home or clinic-based uses. Comparatively, rapid antigen tests are cost-effective and user friendly but lack in sensitivity and specificity. Here we report on the development of a one-pot, duplexed reverse transcriptase recombinase polymerase amplification SARS-CoV-2 assay with MS2 bacteriophage as a full process control. Detection is carried out with either real-time fluorescence or lateral flow readout with an analytical sensitivity of 50 copies per reaction. Unlike previously published assays, the RNA-based MS2 bacteriophage control reports on successful operation of lysis, reverse transcription, and amplification. This SARS-CoV-2 assay features highly sensitive detection, visual readout through an LFA strip, results in less than 25 minutes, minimal instrumentation, and a useful process internal control to rule out false negative test results.

Evaluation of the performance of Abbott Panbio™ COVID-19 antigen rapid diagnostic test for the detection of severe acute respiratory syndrome coronavirus 2 at Harar, Eastern Ethiopia

Background

Rapid antigen tests can help in the effective isolation of symptomatic cases and the systematic tracing of close contacts. However, their reliability must be validated before implementing them widely.

Methods

A cross-sectional study was conducted on 236 COVID-19-suspected patients visiting four different health institutions in Harari Regional State, Harar, Eastern Ethiopia, from June to July 2021. Two nasopharyngeal samples were collected and processed by the Panbio™ Ag-RDT kit and qRT-PCR. The collected data were analyzed using SPSS version 25.0.

Results

The Panbio tests had a sensitivity of 77.5% (95% CI: 61.6-89.2%) and a specificity of 98.5% (95% CI: 95.6-99.7%). It also had a positive predictive value of 91.2% (95% CI: 76.9-96.9%), a negative predictive value of 95.5% (95% CI: 92.3-97.4%), and a kappa of 0.81 (95% CI: 0.7-0.9). The test had a sensitivity of 94.4%, 100%, 100%, and 90% in the samples collected from patients within the 1-5 days post-onset of COVID-19 signs and symptoms, of age group ≤18 years old, with cycle threshold values of <20, and with household contact, respectively.

Conclusion

This test can be used as point-of-care testing for the diagnosis of symptomatic patients with short clinical courses and contact with patients in households.

Rapid Antigen Tests during the COVID-19 Era in Korea and Their Implementation as a Detection Tool for Other Infectious Diseases

Rapid antigen tests (RATs) are diagnostic tools developed to specifically detect a certain protein of infectious agents (viruses, bacteria, or parasites). RATs are easily accessible due to their rapidity and simplicity. During the COVID-19 pandemic, RATs have been widely used in detecting the presence of the specific SARS-CoV-2 antigen in respiratory samples from suspected individuals. Here, the authors review the application of RATs as detection tools for COVID-19, particularly in Korea, as well as for several other infectious diseases. To address these issues, we present general knowledge on the design of RATs that adopt the lateral flow immunoassay for the detection of the analyte (antigen). The authors then discuss the clinical utilization of the authorized RATs amidst the battle against the COVID-19 pandemic in Korea and their role in comparison with other detection methods. We also discuss the implementation of RATs for other, non-COVID-19 infectious diseases, the challenges that may arise during the application, the limitations of RATs as clinical detection tools, as well as the possible problem solving for those challenges to maximize the performance of RATs and avoiding any misinterpretation of the test result.