Limitations of point-of-care testing for low SARS CoV-2 loads: Insights for future pandemics

African Journal of Primary Health Care & Family Medicine

 
 
Field Value
 
Title Limitations of point-of-care testing for low SARS CoV-2 loads: Insights for future pandemics
 
Creator Rukasha, Ivy
 
Subject primary healthcare poor performance; point-of-care tests; COVID-19; low viral load; antigen tests; diagnostic accuracy; SARS CoV-2.
Description Background: The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has seen a surge in the development of diagnostic assays. However, the performance of antigen point-of-care tests (Ag-POCTs) on samples with low viral load has not been evaluated.Aim: To evaluate the accuracy of three World Health Organization (WHO) certified Ag-POCTs in comparison to the reverse transcription polymerase chain reaction (RT-PCR) technique.Setting: The study was conducted at Pietersburg Hospital Limpopo, South Africa between March 2020 and April 2023.Methods: A total of 371 SARS-CoV-2 nasopharyngeal samples from the National Health Laboratory Service were tested using Ag-POCTs from Abbott Panbio, Roche RDT and SD Biosensor, following manufacturer instructions. All samples had RT-PCR results with Ct values between 13 and 45. Reverse transcription polymerase chain reaction results were compared and correlated with Ag-POCT results.Results: Of the 371 samples, the SD Biosensor Standard Q test kit detected the most positive isolates 166 (44.7%), followed by the Abbott Panbio. A total of 153 (41.2%) positives, while the Roche SD detected 134 (36.1%) samples. High viral load (Ct 25) sensitivity and specificity exceeded 77%, while intermediate (Ct 25–35) and low viral load (Ct 35) sensitivity and sensitivity dropped to 32% and 7%, respectively.Conclusion: The performance rapid antigen tests was low on samples with low viral load with results markedly different from the manufacturer’s reported performance.Contribution: Rapid antigen tests should not be used alone for diagnosis, especially in samples with low viral load.
 
Publisher AOSIS
 
Contributor Medical Research of South Africa (MRC)
Date 2025-03-20
 
Type info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion — Qualitative Research
Format text/html application/epub+zip text/xml application/pdf
Identifier 10.4102/phcfm.v17i1.4671
 
Source African Journal of Primary Health Care & Family Medicine; Vol 17, No 1 (2025); 7 pages 2071-2936 2071-2928
 
Language eng
 
Relation
The following web links (URLs) may trigger a file download or direct you to an alternative webpage to gain access to a publication file format of the published article:

https://phcfm.org/index.php/phcfm/article/view/4671/8037 https://phcfm.org/index.php/phcfm/article/view/4671/8038 https://phcfm.org/index.php/phcfm/article/view/4671/8039 https://phcfm.org/index.php/phcfm/article/view/4671/8040
 
Coverage Limpopo; South Africa 2022 -2023 diagnosis
Rights Copyright (c) 2025 Ivy Rukasha https://creativecommons.org/licenses/by/4.0
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