Acta tropica最新文献

{"title":"Determinants of Clonorchis sinensis infection and subsequent treatment: a qualitative study in Guangxi, China","authors":"Yu-Ying Zhu ,&nbsp;Jia-Guang Zhao ,&nbsp;Lu-Yuan Zhao ,&nbsp;Chang-Hai Zhou ,&nbsp;Jun Meng ,&nbsp;Zhi-Hua Jiang ,&nbsp;Shi-Zhu Li ,&nbsp;Men-Bao Qian","doi":"10.1016/j.actatropica.2025.107664","DOIUrl":"10.1016/j.actatropica.2025.107664","url":null,"abstract":"<div><div>Clonorchiasis is caused by the ingestion of raw freshwater fish containing the metacercariae of <em>Clonorchis sinensis</em>. High burden is exerted by clonorchiasis in East Asia, especially in China. Treatment is compulsory to control the morbidity, while mass drug administration and selective drug administration are recommended in high endemic areas. Few qualitative studies have been implemented to explore the knowledge, attitudes, and practices (KAP) towards clonorchiasis as well as the treatment. In 2024, a qualitative cross-sectional study was conducted in two clonorchiasis-endemic villages of Binyang county, Guangxi, China. A total of ten focus group discussions (FGDs) were carried out, involving 52 participants (10 village leaders, 2 village doctors and 40 villagers). Interview focused on the knowledge on harm, transmission, treatment and prevention of clonorchiasis, and attitudes and practices to ingesting raw freshwater fish (<em>“yusheng”</em>) and treatment. Recorded data were transcribed and analyzed manually by using thematic analysis. About half of the participants (25/52) reported the practice of consuming <em>“yusheng”</em>, with a higher percentage in males (84.00 %, 21/25) than in females (16.00 %, 4/25), which is relevant to the differences in dietary predilection and social roles. Especially, a dinner party at festivals is an important contributor in male’s ingestion of “<em>yusheng</em>”. Although 76.92 % of the participants (40/52) acknowledged the potential health risks associated with the ingestion of <em>“yusheng”</em>, most were unaware of the severe morbidities caused by <em>C. sinensis</em>. Furthermore, some people hold a misconception on the additional nutritional value of “<em>yusheng</em>”. Most of the participants (88.46 %, 46/52) had not undergone treatment for clonorchiasis. The participants tended to take medicine while a definite diagnosis of infection was made, and especially low compliance was demonstrated in the individuals without the practice of ingesting <em>“yusheng”</em>. Additionally, the price of the drug and delivery approach also impacted their choices. Village leaders and doctors believed the importance to implement control for clonorchiasis, and health education was suggested to increase the compliance in treatment. In the studied areas, the endemicity of clonorchiasis is driven by the cultural identification, inadequate knowledge, as well as misconception, which demonstrate significant difference in different populations. The choice of treatment is highly impacted by the definite diagnosis and individual’s dietary habit, which may hinder the adoption of drug administration at population level. To control and prevent clonorchiasis, health education is suggested to increase the knowledge including the harm and importance of subsequent drug administration.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"267 ","pages":"Article 107664"},"PeriodicalIF":2.1,"publicationDate":"2025-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144131987","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A high-resolution GIS and machine learning approach for targeted disease management and localized risk assessment in an urban setup: A case study from Bhopal, Central India","authors":"Deepanker Das ,&nbsp;Siddhartha Maiti ,&nbsp;Devojit Kumar Sarma","doi":"10.1016/j.actatropica.2025.107662","DOIUrl":"10.1016/j.actatropica.2025.107662","url":null,"abstract":"<div><div>Predicting dengue distribution based on environmental factors is crucial for effective vector control and management as environmental factors like temperature, demographics, and artificial changes such as roads and buildings significantly influence dengue distribution. The use of new, emerging machine-learning techniques can aid in accurately predicting these cases and developing early warning systems. In this study, we divided our study area, Bhopal city, into 643 polygons of one square kilometre area and collected data on environmental and other factors. Dengue cases from 2012 to 2022 were mapped into these units and divided them into five categories. To find the best predictive model, we evaluated popular machine learning algorithms such as support vector machine (SVM), logistic regression, neural networks, random forest, k-Nearest Neighbors (kNN), and tree using parameters like area under the receiver operating characteristic (ROC) curve (AUC), classification accuracy (CA), F1 score, precision, and recall. The neural network performed the best, with an AUC of 0.921, CA of 0.755, F1 score of 0.740, precision of 0.732, and recall value of 0.755 and was thus selected for future predictions. Among the predictors, building area, population and road density had the highest influence, followed by minimum, maximum, and average temperatures in decreasing order of importance. The machine learning approach neural network effectively predicted the historical dengue distribution considering both landscape and climatic variables for an urban settings like Bhopal. This approach holds potential for application in other cities as well, highlighting the increasing importance of machine learning and predictive modelling in public health.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"267 ","pages":"Article 107662"},"PeriodicalIF":2.1,"publicationDate":"2025-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144126472","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A dendrimer-based dual delivery system for artesunate and fluconazole: Effective malaria treatment in a murine model of Plasmodium berghei","authors":"Fatemeh Babapour ,&nbsp;Faride Khanabadi ,&nbsp;Shohreh Fahimirad ,&nbsp;Seyedeh Shaghayegh Hosseini ,&nbsp;Taher Elmi","doi":"10.1016/j.actatropica.2025.107663","DOIUrl":"10.1016/j.actatropica.2025.107663","url":null,"abstract":"<div><h3>Purpose</h3><div>The increasing prevalence of <em>Plasmodium</em> resistance to conventional artemisinin-based combination therapies (ACTs) presents a significant threat to global malaria control. To address this, we developed a nanocarrier-based co-delivery system (ND-ARS/FLZ) encapsulating artesunate (ARS) and fluconazole (FLZ), aimed at enhancing therapeutic efficacy and overcoming drug resistance in a murine model of <em>Plasmodium berghei</em> infection. The rationale for combining ARS, an antimalarial, with FLZ, an antifungal, stems from recent studies indicating potential synergistic effects on <em>Plasmodium</em> metabolism and drug resistance mechanisms.</div></div><div><h3>Methods</h3><div>The ND-ARS/FLZ nanocarrier was synthesized using a second-generation dendrimer platform, and its structural characteristics were analyzed using Fourier-transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), and scanning electron microscopy (SEM). Encapsulation efficiency and drug loading were also determined. Antiplasmodial efficacy was assessed by quantifying parasitemia on day 4 post-treatment in infected mice. Histopathological analysis of liver tissue was performed to evaluate safety and biocompatibility. Statistical significance was determined using SPSS.</div></div><div><h3>Results</h3><div>The ND-ARS/FLZ nanocarrier exhibited a spherical morphology with a mean diameter of 137 nm and demonstrated sustained drug release, achieving 98 % FLZ and 92 % ARS release within 42 h. At a dose of 400 mg/kg (80 mg ARS + 44 mg FLZ), ND-ARS/FLZ achieved complete parasitemia clearance (100 %), significantly outperforming monotherapies (<em>P</em> &lt; 0.01). The estimated ED₅₀ was 146 mg/kg, indicating potent antimalarial activity. No histopathological signs of hepatotoxicity were observed (<em>P</em> &gt; 0.05), supporting the formulation’s favorable safety profile. The PEGylated dendrimer core, combined with a citric acid-functionalized surface, enhanced the antimalarial efficacy of encapsulated drugs while concurrently minimizing off-target toxicity.</div></div><div><h3>Conclusion</h3><div>The ND-ARS/FLZ nanocarrier exhibits potent antimalarial activity and a promising safety profile, positioning it as a potential candidate for treating drug-resistant malaria. The synergistic drug combination, coupled with nanocarrier-mediated delivery, offers a novel approach to overcoming resistance. Future studies should further explore the pharmacokinetics, host-parasite interactions, and mechanisms of action using techniques such as mass spectrometry, NMR, and in vivo imaging to facilitate preclinical advancement.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"267 ","pages":"Article 107663"},"PeriodicalIF":2.1,"publicationDate":"2025-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144131985","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"New insights on the Rickettsia-tick-wild bird associations in the Western Amazon, Brazil","authors":"Vanessa Lima de Souza ,&nbsp;Francisco Borges Costa ,&nbsp;Richard de Campos Pacheco ,&nbsp;Thiago Fernandes Martins ,&nbsp;Edson Guilherme ,&nbsp;Ednaira Alencar dos Santos ,&nbsp;Victória Luiza de Barros Silva ,&nbsp;Jônatas Lima ,&nbsp;José Ribamar Lima-de-Souza","doi":"10.1016/j.actatropica.2025.107647","DOIUrl":"10.1016/j.actatropica.2025.107647","url":null,"abstract":"<div><div>Several studies have highlighted the importance of balancing wildlife and plant life to mitigate the spread of ticks and their pathogenic microorganisms. This balance is essential for preserving the health of wildlife, domestic animals, and, consequently, human populations. However, human activities, characterized by habitat destruction and fragmentation, have brought humans and domestic animals closer to wild bird populations, which act as dispersers of ticks of public health importance. In light of these challenges, this study aimed to determine the frequency of occurrence and abundance of tick species in wild birds in the upland forests of the southwestern Brazilian Amazon. Data were collected in two municipalities: Rio Branco (four urban forest fragments) and Manoel Urbano (an area of continuous forest in the Parque Estadual Chandless), both located in the state of Acre, Brazil. Birds were captured between May and September 2021 using 10 mist nets placed in five transects of each study area, resulting in a sampling effort of 1210 net hours. Captured birds were thoroughly inspected for tick infestation, and when found, they were removed using forceps. These ticks were identified using a stereomicroscope and specific taxonomic keys, as well as molecular analysis by PCR. We captured 315 birds, of which 95 (30.15 %) were infested with ticks in the larval and nymph stages. A total of 368 ticks belonging to the genus <em>Amblyomma</em> were collected. This included species such as <em>Amblyomma coelebs, Amblyomma geayi, Amblyomma humerale, Amblyomma longirostre, Amblyomma nodosum</em>, and <em>Amblyomma maculatum</em> sensu lato (s.l.)<em>.</em> These results highlight 13 new associations between wild birds and ticks of the genus <em>Amblyomma</em> and reveal, for the first time, the presence of <em>Amblyomma maculatum</em> s.l. and rickettsiae from the Spotted Fever Group. These findings expand the knowledge of the epidemiology of ticks and rickettsial agents of public health importance in the region.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"266 ","pages":"Article 107647"},"PeriodicalIF":2.1,"publicationDate":"2025-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144089489","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Predicting the potential distribution of Aedes albopictus in the Black Sea region at the range edge","authors":"Filiz Gunay ,&nbsp;Alparslan Yildirim ,&nbsp;Ekaterine Zangaladze ,&nbsp;Nathan Burkett-Cadena ,&nbsp;Tamar Kutateladze ,&nbsp;Zafer Pekmezci ,&nbsp;Ahsen Meliha Toroslu ,&nbsp;Alina Denis Kizgin ,&nbsp;Batuhan Askim Arslanhan ,&nbsp;Samba Deguene Diop ,&nbsp;Simge Sahin ,&nbsp;Abdullah Inci ,&nbsp;Nato Dolidze ,&nbsp;Vitalii Rudik ,&nbsp;Barry Alto ,&nbsp;Lindsay P. Campbell","doi":"10.1016/j.actatropica.2025.107661","DOIUrl":"10.1016/j.actatropica.2025.107661","url":null,"abstract":"<div><div><em>Aedes albopictus</em> is a globally invasive species and a major vector of multiple arboviruses that cause human disease. The species has been spreading throughout the Black Sea region since 2011, posing an important public health threat. Here, we use a species distribution modeling to predict the potential distribution of <em>Ae. albopictus</em> including updated field collections from the Black Sea region and georeferenced occurrence data from the European Centre for Disease Prevention and Control, Global Biodiversity Information Facility, and Mosquito Alert. Temperature and precipitation values from WorldClim Bioclimatic data and LandScan human population density data served as environmental variables, and models were run using a maximum entropy algorithm in the Maxent program. Human population density contributed the greatest to model performance, followed by minimum temperature of the coldest month. In the Black Sea region, we observed patchy but notable increases in predicted suitability compared to previous global models, including in less densely populated areas. In addition to multiple coastal areas, temperate rainforests of the Caucasus and around the Bosphorus were predicted to be highly suitable for <em>Ae. albopictus</em>. Our field collections confirm <em>Ae. albopictus</em> at high elevations (1779 m), highlighting the need to include habitats at the interface of areas predicted environmentally unsuitable in transboundary surveillance efforts. Model outputs provide new information for institutions monitoring the spread of this invasive vector. Results indicate the need for comprehensive, region-focused surveillance and control strategies to mitigate <em>Ae. albopictus</em> expansion in areas previously considered unsuitable in Georgia, Turkey, Ukraine, and their neighboring countries.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"267 ","pages":"Article 107661"},"PeriodicalIF":2.1,"publicationDate":"2025-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144109378","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In vivo evaluation of three isoxazolines against Cx. tritaeniorhynchus (Diptera: Culicidae): A novel approach to control Japanese encephalitis vector","authors":"Smrutidhara Dash ,&nbsp;Sundharesan Munusamy ,&nbsp;Balamurugan Mookiah ,&nbsp;Vijayakumar Balakrishnan ,&nbsp;Appadurai Daniel Reegan ,&nbsp;Nisha Mathew ,&nbsp;Manju Rahi ,&nbsp;Ashwani Kumar","doi":"10.1016/j.actatropica.2025.107660","DOIUrl":"10.1016/j.actatropica.2025.107660","url":null,"abstract":"<div><div>As <em>Culex tritaeniorhynchus</em> the primary vector of JE is a highly zoophagic and exophilic nature, a novel vector control approach use of isoxazolines drugs (Sarolaner, Fluralaner and Afoxolane) to reduce the survival of blood-fed mosquito was studied by <em>in vivo</em> model using <em>Rattus norvegicus</em> as an experimental animal. All the drugs are orally administered to the animal with therapeutic dosage. The drugs Fluralaner, Sarolaner and Afoxolaner induced 100 % mortality of <em>Cx. tritaeniorhynchus</em> up to 32, 7 and 20 days respectively after administered to the <em>R. norvegicus</em>. When <em>Cx. tritaeniorhynchus</em> was fed on animals treated with Fluralaner, the median survival duration was 12 h from days 1 to 7 of post-treatment and 24 h from days 8 to 28.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"267 ","pages":"Article 107660"},"PeriodicalIF":2.1,"publicationDate":"2025-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144101065","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exploring spatiotemporal dynamics and climatic effects on dengue in Amazonas, Peru during 2000–2023","authors":"Fátima Burgos ,&nbsp;Milagros Saavedra-Samillán ,&nbsp;Pershing Bustamante-Chauca ,&nbsp;Victor Vera-Ponce ,&nbsp;Carmen Gutierrez ,&nbsp;Jesús Rascón ,&nbsp;Rafael Tapia-Limonchi ,&nbsp;Stella M. Chenet","doi":"10.1016/j.actatropica.2025.107659","DOIUrl":"10.1016/j.actatropica.2025.107659","url":null,"abstract":"<div><div>Peru experienced its most severe dengue outbreak on record, with the Amazonas region reporting 3502 dengue cases in 2022. This study aimed to examine the distribution of dengue cases across Amazonas from 2000 to 2023, while exploring the influence of climate factors. Monthly incidence was aggregated into four consecutive six-year blocks to identify incidence trends, and space-time scan statistics identified high and low-risk clusters. Spearman correlations with distributed lags (0 – 2 months) evaluated the association between incidence and climatic data from NASA-POWER, stratified by season. Until 2005, transmission was restricted to Bagua and Utcubamba provinces. A major increase in cases from 2008 to 2011 was recorded in the endemic provinces of Condorcanqui, Bagua, and Utcubamba forming a high-risk cluster in the latter two (LLR = 287.88, RR = 3.79). After a decrease during 2012–2017, incidence resurged creating a Bagua mega-cluster (LLR = 1112.28, RR = 3.20) and expanding to Jazán and Balsas districts, with the latter characterized by lower temperatures compared to endemic areas. Significant correlations were found between climatic variables and incidence. Specifically, minimum temperature significantly influenced dengue dynamics and expansion into Balsas (rho = 0.23, <em>P</em> = 0.03), with a two-month lag during the wet season. These findings underscore the importance of climate monitoring in guiding public health interventions. However, a comprehensive approach that considers environmental and behavioral factors, tailored to the specific conditions of each province, is essential for effective control of future outbreaks.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"267 ","pages":"Article 107659"},"PeriodicalIF":2.1,"publicationDate":"2025-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144101036","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improving human brucellosis susceptibility mapping using effective and simultaneously metaheuristic-based feature selection and hyperparameter tuning","authors":"Iman Zandi ,&nbsp;Ali Jafari ,&nbsp;Ali Asghar Alesheikh","doi":"10.1016/j.actatropica.2025.107657","DOIUrl":"10.1016/j.actatropica.2025.107657","url":null,"abstract":"<div><div>Human Brucellosis, a neglected zoonotic disease, affects 1.6 to 2.1 million people globally each year. In Iran, it has become a significant health concern, with an average annual incidence rate of 19.91 cases per 100,000 people. This study aims to create a reliable Human Brucellosis Susceptibility Map (HBSM) for Mazandaran Province using a hybrid machine learning approach that enhances performance through metaheuristic algorithms for feature and hyperparameter optimization. A transformation function is integrated into these algorithms to reduce computational and time complexities while simultaneously executing feature selection and hyperparameter tuning. Additionally, a two-phase mutation operator is employed to improve the performance of feature selection. The results indicate that the hybrid model of Support Vector Regression-Transformation Mutation Grey Wolf Optimizer (SVR-TMGWO) outperformed other models, achieving RMSE=0.7723, MAE=0.614, MdAE=0.473, and <em>R</em> = 0.536. The predicted HBSM for 2018 identified 68 rural districts in Mazandaran Province as being in the High and Very High susceptibility classes. The susceptibility map can help decision-makers more effectively prevent, control, and manage Human Brucellosis in Mazandaran Province.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"267 ","pages":"Article 107657"},"PeriodicalIF":2.1,"publicationDate":"2025-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144101064","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unravelling the consortium of the cercarial dermatitis in lake from a basin of Argentinian Central Andes: histological and phylogenetic insights of Chilina snail and their fluke partner","authors":"Federico A. Dellagnola ,&nbsp;Alberto Nadim Yunes ,&nbsp;Israel A. Vega","doi":"10.1016/j.actatropica.2025.107650","DOIUrl":"10.1016/j.actatropica.2025.107650","url":null,"abstract":"<div><div>In the context of a research program dealing with the symbiotic associations between aquatic snails and trematodes, we studied a host-parasite consortium in Lake El Nihuil (Mendoza, Argentina), a water body from Atuel river basin (Central Andes) in which recent outbreaks of cercarial dermatitis (‘swimmer's itch’) occurred. According to the morphological traits and molecular phylogenetic analyses (mitochondrial COI and 16S rRNA genes), the gastropod host was assigned to the endemic genus <em>Chilina</em>. The snails hosted and released a schistosomatid brevifurcate apharingeate cercaria, whose phylogenetic position was inferred using 28S rRNA subunit gene and 18S-ITS1-5.8S rRNA ribosomal region. The parasite was placed in a clade together with sequences from 'Furcocercariae Lineage II', avian schistosomes closely related to the recently named genus <em>Nasusbilharzia</em>, whose final host, the endemic black-necked swan, occurs in Lake El Nihuil. The infected specimens of <em>Chilina</em> sp. showed abundant parasite larvae placed between haemocoelic spaces and connective tissues, modifying the histological architecture of the digestive gland-gonad complex. Parasites produced a decrease in the number of glandular acini and atrophy of the reproductive tissue. This work suggests a displacement of the swimmer's itch outbreaks towards lower latitudes, highlighting the need for the implementation of multidisciplinary studies to monitor these emerging diseases in association with specific symbiotic consortiums.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"267 ","pages":"Article 107650"},"PeriodicalIF":2.1,"publicationDate":"2025-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144092310","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Population genetic structure of Biomphalaria snails found in East Africa’s river systems","authors":"Victor O. Magero ,&nbsp;Sammy Kisara ,&nbsp;Mbaruk A. Suleman ,&nbsp;Christopher M. Wade","doi":"10.1016/j.actatropica.2025.107656","DOIUrl":"10.1016/j.actatropica.2025.107656","url":null,"abstract":"&lt;div&gt;&lt;div&gt;There is a need for current and more detailed information on the population genetic structure of &lt;em&gt;Biomphalaria&lt;/em&gt; snails in East Africa’s river systems. Here, we examine the population genetic structure of &lt;em&gt;Biomphalaria&lt;/em&gt; populations in East Africa using the mitochondrial cytochrome oxidase 1 (CO1) gene and the internal transcribed spacer 2 (ITS-2) region of nuclear ribosomal DNA. &lt;em&gt;Biomphalaria&lt;/em&gt; snails were found at 31 of the 172 sites surveyed, with &lt;em&gt;B. pfeifferi&lt;/em&gt; snails found at 23 sites and snails of the &lt;em&gt;Biomphalaria&lt;/em&gt; ‘Nilotic Species Complex’ found at 9 sites. &lt;em&gt;Biomphalaria pfeifferi&lt;/em&gt; formed a monophyletic group in both CO1 and ITS-2 phylogenetic trees. Similarly, the ‘Nilotic Species Complex’ also formed a monophyletic group in both CO1 and ITS-2 trees but while some individual species within the 'Nilotic Species Complex’ were monophyletic, others were not monophyletic and intermingled in the trees.&lt;/div&gt;&lt;div&gt;A total of 17 CO1 haplotypes (3 shared haplotypes and 14 private haplotypes) were identified for &lt;em&gt;B. pfeifferi&lt;/em&gt; populations with a haplotype diversity of 0.798 and nucleotide diversity of 0.004. For ITS-2, a total of 27 &lt;em&gt;B. pfeifferi&lt;/em&gt; haplotypes (3 shared haplotypes and 24 private haplotypes) were identified, with a haplotype diversity of 0.471 and nucleotide diversity of 0.002. For the ‘Nilotic Species Complex’, a total of 21 CO1 haplotypes (all private) were identified, with a haplotype diversity of 0.897 and nucleotide diversity of 0.018. For ITS-2, a total of 23 ‘Nilotic Species Complex’ ITS-2 haplotypes (3 shared haplotypes and 20 private haplotypes) were identified with a haplotype diversity of 0.951 and nucleotide diversity of 0.008.&lt;/div&gt;&lt;div&gt;Analysis of Molecular Variance (AMOVA) revealed low genetic variation within &lt;em&gt;B. pfeifferi&lt;/em&gt; populations (between 4.83 % and 5.86 %) and high genetic differentiation among populations (between 94.14 % and 95.17 %). For the ‘Nilotic Species Complex’, the genetic diversity was moderate within populations (between 27.83 % and 31.96 %) and among populations (between 68.04 % and 72.17 %). Geographical distance plays a role in bringing about genetic differentiation among &lt;em&gt;Biomphalaria&lt;/em&gt; populations in East Africa’s river systems, with sequences from &lt;em&gt;Biomphalaria&lt;/em&gt; populations that were found at sites close to each other geographically, taking positions close to each other in the phylogenetic trees.&lt;/div&gt;&lt;div&gt;&lt;em&gt;B. pfeifferi&lt;/em&gt; populations studied herein were characterised by low intra-population genetic diversity and high inter-population genetic diversity suggestive of low levels of gene flow and high levels of inbreeding. In the case of the ‘Nilotic Species Complex’, there was moderate to high levels of intra-population genetic diversity and moderate to high levels of inter-population genetic differentiation suggestive of high levels of gene flow. It was established that the population genetic structure of &lt;em","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"267 ","pages":"Article 107656"},"PeriodicalIF":2.1,"publicationDate":"2025-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144092301","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}