{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,20]],"date-time":"2026-10-20T21:12:50Z","timestamp":1792530770765,"version":"4.5.0"},"reference-count":20,"publisher":"AOSIS","issue":"1","license":[{"start":{"date-parts":[[2025,3,20]],"date-time":"2025-03-20T00:00:00Z","timestamp":1742428800000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"abstract":"<jats:p>Background:\u00a0The 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.\n\nAim:\u00a0To evaluate the accuracy of three World Health Organization (WHO) certified Ag-POCTs in comparison to the reverse transcription polymerase chain reaction (RT-PCR) technique.\n\nSetting:\u00a0The study was conducted at Pietersburg Hospital Limpopo, South Africa between March 2020 and April 2023.\n\nMethods:\u00a0A 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.\n\nResults:\u00a0Of 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 &lt; 25) sensitivity and specificity exceeded 77%, while intermediate (Ct 25\u201335) and low viral load (Ct &gt; 35) sensitivity and sensitivity dropped to 32% and 7%, respectively.\n\nConclusion:\u00a0The performance rapid antigen tests was low on samples with low viral load with results markedly different from the manufacturer\u2019s reported performance.\n\nContribution:\u00a0Rapid antigen tests should not be used alone for diagnosis, especially in samples with low viral load.<\/jats:p>","DOI":"10.4102\/phcfm.v17i1.4671","type":"journal-article","created":{"date-parts":[[2025,3,20]],"date-time":"2025-03-20T21:09:17Z","timestamp":1742504957000},"update-policy":"https:\/\/doi.org\/10.4102\/crossmark-policy","source":"Crossref","is-referenced-by-count":4,"title":["Limitations of point-of-care testing for low SARS CoV-2 loads: Insights for future pandemics"],"prefix":"10.4102","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0009-0006-8345-4535","authenticated-orcid":false,"given":"Ivy","family":"Rukasha","sequence":"first","affiliation":[{"id":[{"id":"https:\/\/ror.org\/017p87168","id-type":"ROR","asserted-by":"publisher"}],"name":"University of Limpopo"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"2580","published-online":{"date-parts":[[2025,3,20]]},"reference":[{"key":"ref0","doi-asserted-by":"crossref","unstructured":"Galv\u00e1n P, Fusillo J, Gonz\u00e1lez F, et al. 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