{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T11:21:21Z","timestamp":1785410481149,"version":"3.56.0"},"reference-count":44,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2026,5,8]],"date-time":"2026-05-08T00:00:00Z","timestamp":1778198400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Water Research Commission of South Africa","award":["2022\/2023-00834"],"award-info":[{"award-number":["2022\/2023-00834"]}]},{"award":["2022\/2023-00834"],"award-info":[{"award-number":["2022\/2023-00834"]}],"id":[{"id":"https:\/\/ror.org\/02qv02186","id-type":"ROR","asserted-by":"publisher"}]},{"name":"PM"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diseases"],"abstract":"<jats:p>Background\/Objectives: Intestinal schistosomiasis caused by Schistosoma mansoni is often underestimated in low-transmission settings due to the limited sensitivity of traditional stool microscopy. More sensitive approaches, including antigen detection and molecular diagnostics, are required to detect infections where egg excretion is low or intermittent. This study aimed to determine the prevalence of S. mansoni infection among school-going children in Nelson Mandela Bay (NMB) using a multi-modal diagnostic approach. Methods: This cross-sectional study included 759 schoolchildren aged 5\u201314 years from 15 primary schools in NMB. Stool samples were analyzed using the Kato\u2013Katz technique to detect S. mansoni eggs, while urine samples were tested using the point-of-care circulating cathodic antigen (POC-CCA) assay for antigen detection. A subset of stool samples from POC-CCA-positive participants (n = 28) was further analyzed using conventional PCR (cPCR), targeting the S. mansoni cox1 gene, for molecular confirmation. Only a single stool specimen was collected per participant. Results: Among the 759 participants (58% male, 42% female), no egg-positive cases were detected. However, POC-CCA testing identified S. mansoni antigen in 3.2% of participants. Of the 28 POC-CCA-positive samples analyzed by cPCR, 9 (32.1%) were PCR-positive, representing molecular confirmation within the antigen-positive subset rather than overall prevalence. Conclusions: Traditional microscopy underestimated S. mansoni prevalence in this low-prevalence setting. Antigen detection combined with molecular diagnostics improved case identification and highlighted ongoing transmission. These findings support the integration of sensitive diagnostic tools into schistosomiasis surveillance and control strategies in South Africa.<\/jats:p>","DOI":"10.3390\/diseases14050164","type":"journal-article","created":{"date-parts":[[2026,5,11]],"date-time":"2026-05-11T19:35:43Z","timestamp":1778528143000},"page":"164","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Diagnostic Performance and Discordance of Kato\u2013Katz Method, POC-CCA Test, and PCR in Detecting Schistosoma mansoni in a Low-Prevalence South African Setting"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-0161-1607","authenticated-orcid":false,"given":"Maryline","family":"Vere","sequence":"first","affiliation":[{"name":"Department of Environmental Health, Faculty of Health Sciences, Nelson Mandela University, Summerstrand, Gqeberha 6001, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2253-6354","authenticated-orcid":false,"given":"Wilma ten","family":"Ham-Baloyi","sequence":"additional","affiliation":[{"name":"Department of Environmental Health, Faculty of Health Sciences, Nelson Mandela University, Summerstrand, Gqeberha 6001, South Africa"},{"name":"Department of Nursing Science, Faculty of Health Sciences, Nelson Mandela University, Summerstrand, Gqeberha 6001, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lucy","family":"Ochola","sequence":"additional","affiliation":[{"name":"Department of Environmental Health, Faculty of Health Sciences, Nelson Mandela University, Summerstrand, Gqeberha 6001, South Africa"},{"name":"Department of Tropical and Infectious Diseases, Kenya Institute of Primate Research, Nairobi 00502, Kenya"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Opeoluwa","family":"Oyedele","sequence":"additional","affiliation":[{"name":"Department of Environmental Health, Faculty of Health Sciences, Nelson Mandela University, Summerstrand, Gqeberha 6001, South Africa"},{"name":"Department of Computing, Mathematical and Statistical Sciences, School of Science, University of Namibia, Windhoek 9000, Namibia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lindsey","family":"Beyleveld","sequence":"additional","affiliation":[{"name":"Department of Medical Laboratory Science, Faculty of Health Sciences, Nelson Mandela University, Summerstrand, Gqeberha 6001, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Siphokazi","family":"Tili","sequence":"additional","affiliation":[{"name":"Department of Medical Laboratory Science, Faculty of Health Sciences, Nelson Mandela University, Summerstrand, Gqeberha 6001, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Takafira","family":"Mduluza","sequence":"additional","affiliation":[{"name":"Department of Biochemistry and Biotechnology, University of Zimbabwe, Harare P.O. Box MP 167, Zimbabwe"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paula","family":"Melariri","sequence":"additional","affiliation":[{"name":"Department of Environmental Health, Faculty of Health Sciences, Nelson Mandela University, Summerstrand, Gqeberha 6001, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"15","DOI":"10.1186\/s40249-021-00798-4","article-title":"Detection of Schistosoma mansoni DNA using polymerase chain reaction from serum and dried blood spot card samples of an adult population in North-western Tanzania","volume":"10","author":"Fuss","year":"2021","journal-title":"Infect. Dis. 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