{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T17:08:52Z","timestamp":1785431332533,"version":"3.56.0"},"reference-count":44,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2026,5,15]],"date-time":"2026-05-15T00:00:00Z","timestamp":1778803200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Institutes of Health Malaysia"},{"id":[{"id":"https:\/\/ror.org\/045p44t13","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Malaysian Ministry of Health","award":["NMRR-22-00823"],"award-info":[{"award-number":["NMRR-22-00823"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Background: Wastewater-based epidemiology (WBE) is a valuable population-level surveillance tool for monitoring SARS-CoV-2 circulation. However, evidence on optimal viral concentration approaches in confined institutional settings such as prisons remains limited. This study aimed to compare the performance of Direct Capture (DC) and Electronegative Membrane Filtration (EMF) for SARS-CoV-2 RNA detection in wastewater from a prison facility in Selangor, Malaysia. Methods: Composite wastewater samples collected over 18 weeks (April\u2013August 2023; n = 50) were analysed by RT-dPCR targeting the N1 and N2 gene regions, with concentrations normalized to pepper mild mottle virus (PMMoV). DC consistently outperformed EMF across both gene targets. Median concentrations obtained using DC were 11.09 \u00d7 103 copies L\u22121 (N1) and 3.43 \u00d7 103 copies L\u22121 (N2), compared with 0.70 \u00d7 103 copies L\u22121 (N1) and 0.48 \u00d7 103 copies L\u22121 (N2) using EMF. Detection frequencies were higher with DC (N1: 94%, N2: 84%) than with EMF (N1: 88%, N2: 76%). Paired statistical analysis confirmed significant differences between methods (N1: p = 2.3 \u00d7 10\u22127; N2: p = 9.4 \u00d7 10\u22125), and Bland\u2013Altman analysis demonstrated systematic underestimation by EMF (mean bias \u22121.15 log10 for N1; \u22120.87 log10 for N2), indicating that the methods are not analytically interchangeable. Conclusions: Normalization reduced absolute SARS-CoV-2 RNA concentrations while preserving temporal trends, supporting its use to improve comparability across sampling periods. Overall, these findings demonstrate that DC combined with N1 detection provides a more sensitive and reliable approach for SARS-CoV-2 WBE in confined settings, underscoring the importance of methodological optimization to strengthen early-warning capacity in high-risk environments.<\/jats:p>","DOI":"10.3390\/v18050563","type":"journal-article","created":{"date-parts":[[2026,5,19]],"date-time":"2026-05-19T16:07:26Z","timestamp":1779206846000},"page":"563","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Comparative Evaluation of SARS-CoV-2 RNA Concentration and Normalization Strategies in Prison Wastewater: Implications for Viral Dynamics in Confined Environments"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3219-4204","authenticated-orcid":false,"given":"Raheel","family":"Nazakat","sequence":"first","affiliation":[{"name":"Environmental Health Research Centre, Institute for Medical Research, National Institutes of Health, Ministry of Health Malaysia, Shah Alam 40170, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nabilla Athieqa","family":"Mahdzar","sequence":"additional","affiliation":[{"name":"Environmental Health Research Centre, Institute for Medical Research, National Institutes of Health, Ministry of Health Malaysia, Shah Alam 40170, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amirul Haziq","family":"Azwan","sequence":"additional","affiliation":[{"name":"Environmental Health Research Centre, Institute for Medical Research, National Institutes of Health, Ministry of Health Malaysia, Shah Alam 40170, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Reethiya","family":"Letchumanan","sequence":"additional","affiliation":[{"name":"Malaysian Prison Department, Ministry of Home Affairs of Malaysia, Kajang Emenyih Bypass, Kajang 43000, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6609-1529","authenticated-orcid":false,"given":"Siti Aishah","family":"Rashid","sequence":"additional","affiliation":[{"name":"Environmental Health Research Centre, Institute for Medical Research, National Institutes of Health, Ministry of Health Malaysia, Shah Alam 40170, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"425","DOI":"10.4082\/kjfm.20.0117","article-title":"Malaysia Healthcare Early Response in Combatting COVID-19 Pandemic in 2020","volume":"42","author":"Amaran","year":"2021","journal-title":"Korean J. 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