{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,28]],"date-time":"2026-02-28T04:24:53Z","timestamp":1772252693019,"version":"3.50.1"},"reference-count":48,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2019,1,26]],"date-time":"2019-01-26T00:00:00Z","timestamp":1548460800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJERPH"],"abstract":"<jats:p>Understanding the spatially varying effects of demographic factors on the spatio-temporal variation of intestinal parasites infections is important for public health intervention and monitoring. This paper presents a hierarchical Bayesian spatially varying coefficient model to evaluate the effects demographic factors on intestinal parasites morbidities in Ghana. The modeling relied on morbidity data collected by the District Health Information Management Systems. We developed Poisson and Poisson-gamma spatially varying coefficient models. We used the demographic factors, unsafe drinking water, unsafe toilet, and unsafe liquid waste disposal as model covariates. The models were fitted using the integrated nested Laplace approximations (INLA). The overall risk of intestinal parasites infection was estimated to be 10.9 per 100 people with a wide spatial variation in the district-specific posterior risk estimates. Substantial spatial variation of increasing multiplicative effects of unsafe drinking water, unsafe toilet, and unsafe liquid waste disposal occurs on the variation of intestinal parasites risk. The structured residual spatial variation widely dominates the unstructured component, suggesting that the unaccounted-for risk factors are spatially continuous in nature. The study concludes that both the spatial distribution of the posterior risk and the associated exceedance probability maps are essential for monitoring and control of intestinal parasites.<\/jats:p>","DOI":"10.3390\/ijerph16030339","type":"journal-article","created":{"date-parts":[[2019,1,29]],"date-time":"2019-01-29T03:40:55Z","timestamp":1548733255000},"page":"339","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Poisson-Gamma Mixture Spatially Varying Coefficient Modeling of Small-Area Intestinal Parasites Infection"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2206-3662","authenticated-orcid":false,"given":"Frank Badu","family":"Osei","sequence":"first","affiliation":[{"name":"Faculty of Geo-Information Science and Earth Observation (ITC), University of Twente, 7522 NB Enschede, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9456-1233","authenticated-orcid":false,"given":"Alfred","family":"Stein","sequence":"additional","affiliation":[{"name":"Faculty of Geo-Information Science and Earth Observation (ITC), University of Twente, 7522 NB Enschede, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0226-3069","authenticated-orcid":false,"given":"Anthony","family":"Ofosu","sequence":"additional","affiliation":[{"name":"Policy, Planning, Monitoring and Evaluation (PPME)\u2013Ghana Health Service; Accra, Ghana"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,1,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1521","DOI":"10.1016\/S0140-6736(06)68653-4","article-title":"Soil-transmitted helminth infections: Ascariasis, trichuriasis, and hookworm","volume":"367","author":"Bethony","year":"2006","journal-title":"Lancet"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"547","DOI":"10.1016\/j.pt.2003.10.002","article-title":"Soil-transmitted helminth infections: Updating the global picture","volume":"19","author":"Brooker","year":"2003","journal-title":"Trends Parasitol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"e732","DOI":"10.1016\/j.ijid.2009.11.036","article-title":"The global war against intestinal parasites\u2014Should we use a holistic approach?","volume":"14","author":"Alum","year":"2010","journal-title":"Int. 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