{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,28]],"date-time":"2025-12-28T14:31:04Z","timestamp":1766932264881,"version":"build-2065373602"},"reference-count":36,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2025,5,20]],"date-time":"2025-05-20T00:00:00Z","timestamp":1747699200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Advancing Health through Evidence Assisted Decision through Health Policy and Systems Research (AHEAD-HPSR)","award":["2020-11-2750"],"award-info":[{"award-number":["2020-11-2750"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["TropicalMed"],"abstract":"<jats:p>Oncomelania hupensis quadrasi is the intermediate host of S. japonicum, the causative species of schistosomiasis in the Philippines. Conventionally, risk areas are identified by procedures requiring highly skilled personnel and constant surveillance efforts. Recent developments in disease diagnostics explore the utilization of environmental DNA as targets for polymerase chain reactions in disease surveillance. In this study, a low-cost, specific, and efficient SYBR Green-based real-time PCR assay to detect O. h. quadrasi DNA from water samples was developed, optimized, and validated. Primers were designed based on the A18 microsatellite region of O. h. quadrasi. The assay exhibited a detection limit of one copy number per microliter at 99.4% efficiency and R2 = 0.999, which specifically amplified O. h. quadrasi DNA only. Validation of this assay in environmental water samples demonstrated 100% PPV and NPV values, suggesting its potential as a tool for identifying risk areas, pathogen-directed surveillance, policy making, and disease control.<\/jats:p>","DOI":"10.3390\/tropicalmed10050140","type":"journal-article","created":{"date-parts":[[2025,5,20]],"date-time":"2025-05-20T04:48:18Z","timestamp":1747716498000},"page":"140","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Development of a SYBR Green-Based Real-Time PCR Assay to Detect Oncomelania hupensis quadrasi DNA in Environmental Water Samples"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9290-5146","authenticated-orcid":false,"given":"Daria L.","family":"Manalo","sequence":"first","affiliation":[{"name":"Department of Health, Research Institute for Tropical Medicine, 9002 Research Drive, Filinvest Corporate City, Alabang, Muntinlupa City 1781, Philippines"},{"name":"Institute of Biology, University of the Philippines Diliman, Quezon City 1101, Philippines"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-7184-6043","authenticated-orcid":false,"given":"Jude Karlo G.","family":"Bolivar","sequence":"additional","affiliation":[{"name":"Department of Health, Research Institute for Tropical Medicine, 9002 Research Drive, Filinvest Corporate City, Alabang, Muntinlupa City 1781, Philippines"},{"name":"Department of Science and Technology, Science Education Institute, Taguig 1631, Philippines"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Karl Ian T.","family":"Ermino","sequence":"additional","affiliation":[{"name":"Department of Health, Research Institute for Tropical Medicine, 9002 Research Drive, Filinvest Corporate City, Alabang, Muntinlupa City 1781, Philippines"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-9617-0588","authenticated-orcid":false,"given":"Jeromir G.","family":"Bondoc","sequence":"additional","affiliation":[{"name":"Department of Health, Research Institute for Tropical Medicine, 9002 Research Drive, Filinvest Corporate City, Alabang, Muntinlupa City 1781, Philippines"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mark Joseph M.","family":"Espino","sequence":"additional","affiliation":[{"name":"Department of Health, Research Institute for Tropical Medicine, 9002 Research Drive, Filinvest Corporate City, Alabang, Muntinlupa City 1781, Philippines"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Efraim P.","family":"Panganiban","sequence":"additional","affiliation":[{"name":"Department of Health, Research Institute for Tropical Medicine, 9002 Research Drive, Filinvest Corporate City, Alabang, Muntinlupa City 1781, Philippines"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-2500-0161","authenticated-orcid":false,"given":"Kathyleen S.","family":"Nogrado","sequence":"additional","affiliation":[{"name":"Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3969-2660","authenticated-orcid":false,"given":"Raffy Jay C.","family":"Fornillos","sequence":"additional","affiliation":[{"name":"Institute of Biology, University of the Philippines Diliman, Quezon City 1101, Philippines"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mario A.","family":"Jiz","sequence":"additional","affiliation":[{"name":"Immunology Department, Research Institute of Tropical Medicine, Manila 1781, Philippines"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lydia R.","family":"Leonardo","sequence":"additional","affiliation":[{"name":"Institute of Biology, University of the Philippines Diliman, Quezon City 1101, Philippines"},{"name":"Office of Research Coordination, University of the East, 2219 C.M. Recto Avenue, Brgy. 404, Zone 41, Sampaloc, Manila 1008, Philippines"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ian Kendrich C.","family":"Fontanilla","sequence":"additional","affiliation":[{"name":"Institute of Biology, University of the Philippines Diliman, Quezon City 1101, Philippines"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,5,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1016\/j.ijid.2016.01.011","article-title":"National survey data for zoonotic schistosomiasis in the Philippines grossly underestimates the true burden of disease within endemic zones: Implications for future control","volume":"45","author":"Olveda","year":"2016","journal-title":"Int. J. Infect. 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