{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,16]],"date-time":"2026-09-16T00:35:58Z","timestamp":1789518958822,"version":"build-2803163510"},"reference-count":48,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2022,1,28]],"date-time":"2022-01-28T00:00:00Z","timestamp":1643328000000},"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>Background: The epidemiology of schistosomiasis transmission varies depending on the circumstances of the surrounding water bodies and human behaviors. We aimed to explore cercarial emergence patterns from snails that are naturally affected by human schistosomiasis and non-human trematodes. In addition, this study aimed to explore how schistosomiasis infection affects snail survival, reproduction, and growth. Methods: We measured the survival rate, fecundity, and size of Biomphalaria pfeifferi snails and the cercarial rhythmicity of S. haematobium and S. mansoni. The number of egg masses, eggs per egg mass, and snail deaths were counted for 7 weeks. The survival rate and cumulative hazard were assessed for infected and non-infected snails. Results: S. haematobium and S. mansoni cercariae peaked at 9:00\u201311:00 a.m. Infection significantly reduced the survival rate of B. pfeifferi, which was 35% and 51% for infected and non-infected snails, respectively (p = 0.02), at 7 weeks after infection. The hazard ratio of death for infected snails compared to non-infected snails was 1.65 (95% confidence interval: 1.35\u20131.99; p = 0.01). Conclusions: An understanding of the dynamics of schistosomiasis transmission will be helpful for formulating schistosomiasis control and elimination strategies. Cercarial rhythmicity can be reflected in health education, and the reproduction and survival rate of infected snails can be used as parameters for developing disease modeling.<\/jats:p>","DOI":"10.3390\/ijerph19031508","type":"journal-article","created":{"date-parts":[[2022,1,29]],"date-time":"2022-01-29T05:26:17Z","timestamp":1643433977000},"page":"1508","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["The Life Histories of Intermediate Hosts and Parasites of Schistosoma haematobium and Schistosoma mansoni in the White Nile River, Sudan"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6554-9596","authenticated-orcid":false,"given":"Hassan Ahmed Hassan Ahmed","family":"Ismail","sequence":"first","affiliation":[{"name":"Communicable and Non-Communicable Diseases Control Directorate, Federal Ministry of Health, Khartoum 1111, Sudan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abed el Aziz Abed el Rahim Mohamed","family":"Ahmed","sequence":"additional","affiliation":[{"name":"Schistosomiasis Research Laboratory, Zoology Department, Faculty of Science, University of Khartoum, Khartoum 11111, Sudan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1264-3313","authenticated-orcid":false,"given":"Seungman","family":"Cha","sequence":"additional","affiliation":[{"name":"Department of Global Development and Entrepreneurship, Graduate School of Global Development and Entrepreneurship, Handong Global University, Pohang 37554, Korea"},{"name":"Department of Disease Control, London School of Hygiene & Tropical Medicine, London WC1E 7HT, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yan","family":"Jin","sequence":"additional","affiliation":[{"name":"Department of Microbiology, College of Medicine, Dongguk University, Gyeongju 38066, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,1,28]]},"reference":[{"key":"ref_1","unstructured":"WHO (2021). 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