{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,24]],"date-time":"2026-09-24T07:14:17Z","timestamp":1790234057991,"version":"4.1.0"},"reference-count":50,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2018,3,10]],"date-time":"2018-03-10T00:00:00Z","timestamp":1520640000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000005","name":"U.S. Department of Defense","doi-asserted-by":"publisher","award":["DOD-GEIS P0435_14_UN"],"award-info":[{"award-number":["DOD-GEIS P0435_14_UN"]}],"id":[{"id":"10.13039\/100000005","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJERPH"],"abstract":"<jats:p>Cholera emergence is strongly linked to local environmental and ecological context. The 1991\u20132004 pandemic emerged in Per\u00fa and spread north into Ecuador\u2019s El Oro province, making this a key site for potential re-emergence. Machala, El Oro, is a port city of 250,000 inhabitants, near the Peruvian border. Many livelihoods depend on the estuarine system, from fishing for subsistence and trade, to domestic water use. In 2014, we conducted biweekly sampling for 10 months in five estuarine locations, across a gradient of human use, and ranging from inland to ocean. We measured water-specific environmental variables implicated in cholera growth and persistence: pH, temperature, salinity, and algal concentration, and evaluated samples in five months for pathogenic and non-pathogenic Vibrio cholerae, by polymerase chain reaction (PCR). We found environmental persistence of pandemic strains O1 and O139, but no evidence for toxigenic strains. Vibrio cholerae presence was coupled to algal and salinity concentration, and sites exhibited considerable seasonal and spatial heterogeneity. This study indicates that environmental conditions in Machala are optimal for cholera re-emergence, with risk peaking during September, and higher risk near urban periphery low-income communities. This highlights a need for surveillance of this coupled cholera\u2013estuarine system to anticipate potential future cholera outbreaks.<\/jats:p>","DOI":"10.3390\/ijerph15030486","type":"journal-article","created":{"date-parts":[[2018,3,12]],"date-time":"2018-03-12T13:13:48Z","timestamp":1520860428000},"page":"486","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Spatiotemporal Variation in Environmental Vibrio cholerae in an Estuary in Southern Coastal Ecuador"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4308-6321","authenticated-orcid":false,"given":"Sadie","family":"Ryan","sequence":"first","affiliation":[{"name":"Quantitative Disease Ecology and Conservation Lab, Department of Geography, University of Florida, Gainesville, FL 32610 USA"},{"name":"Emerging Pathogens Institute, University of Florida, Gainesville, FL 32610, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anna","family":"Stewart-Ibarra","sequence":"additional","affiliation":[{"name":"Center for Global Health and Translational Science, SUNY Upstate Medical University, Syracuse, NY 13210, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3383-4672","authenticated-orcid":false,"given":"Eunice","family":"Ord\u00f3\u00f1ez-Enireb","sequence":"additional","affiliation":[{"name":"Laboratorio para Investigaciones Biom\u00e9dicas, FCV, Escuela Superior Polit\u00e9cnica del Litoral, Guayaquil 090101, Ecuador"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Winnie","family":"Chu","sequence":"additional","affiliation":[{"name":"Division of Nutritional Sciences, Cornell University, Ithaca, NY 14850, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Julia","family":"Finkelstein","sequence":"additional","affiliation":[{"name":"Division of Nutritional Sciences, Cornell University, Ithaca, NY 14850, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christine","family":"King","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Immunology, SUNY Upstate Medical University, Syracuse, NY 13210, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luis","family":"Escobar","sequence":"additional","affiliation":[{"name":"Center for Global Health and Translational Science, SUNY Upstate Medical University, Syracuse, NY 13210, USA"},{"name":"Department of Fish and Wildlife Conservation, Virginia Tech, Blacksburg, VA 24061, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christina","family":"Lupone","sequence":"additional","affiliation":[{"name":"Center for Global Health and Translational Science, SUNY Upstate Medical University, Syracuse, NY 13210, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Froilan","family":"Heras","sequence":"additional","affiliation":[{"name":"Center for Global Health and Translational Science, SUNY Upstate Medical University, Syracuse, NY 13210, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Erica","family":"Tauzer","sequence":"additional","affiliation":[{"name":"Center for Global Health and Translational Science, SUNY Upstate Medical University, Syracuse, NY 13210, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Egan","family":"Waggoner","sequence":"additional","affiliation":[{"name":"Center for Global Health and Translational Science, SUNY Upstate Medical University, Syracuse, NY 13210, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0694-4702","authenticated-orcid":false,"given":"Tyler","family":"James","sequence":"additional","affiliation":[{"name":"Quantitative Disease Ecology and Conservation Lab, Department of Geography, University of Florida, Gainesville, FL 32610 USA"},{"name":"Emerging Pathogens Institute, University of Florida, Gainesville, FL 32610, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6829-1295","authenticated-orcid":false,"given":"Washington","family":"C\u00e1rdenas","sequence":"additional","affiliation":[{"name":"Laboratorio para Investigaciones Biom\u00e9dicas, FCV, Escuela Superior Polit\u00e9cnica del Litoral, Guayaquil 090101, Ecuador"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mark","family":"Polhemus","sequence":"additional","affiliation":[{"name":"Center for Global Health and Translational Science, SUNY Upstate Medical University, Syracuse, NY 13210, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2018,3,10]]},"reference":[{"key":"ref_1","unstructured":"WHO (2013). 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