Spatial distribution of Biomphalaria spp., the intermediate host snails of Schistosoma mansoni, in Brazil

Scholte, Ronaldo G.C. and Carvalho, Omar S. and Malone, John B. and Utzinger, Jürg and Vounatsou, Penelope (2012) Spatial distribution of Biomphalaria spp., the intermediate host snails of Schistosoma mansoni, in Brazil. Geospatial health, 6 (3). S95-S101. ISSN 1970-7096

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Schistosomiasis mansoni remains an important parasitic disease of man, endemic in large parts of sub-Saharan Africa, the Middle East, South America and the Caribbean. The aetiological agent is the trematode Schistosoma mansoni, whereas aquatic snails of the genus Biomphalaria act as intermediate hosts in the parasite life cycle. In Brazil, the distribution of Biomphalaria spp. is closely associated with the occurrence of schistosomiasis. The purpose of this study was to map and predict the spatial distribution of the intermediate host snails of S. mansoni across Brazil. We assembled snail “presenceonly” data and used a maximum entropy approach, along with climatic and environmental variables to produce predictive risk maps. We identified a series of risk factors that govern the distribution of Biomphalaria snails. We find that high-risk areas for B. glabrata are concentrated in the regions of Northeast and Southeast and the northern part of the South region. B. straminea are found in the Northeast and Southeast regions, and B. tenagophila are concentrated in the Southeast and South regions. Our findings confirm that the presence of the intermediate host snails is correlated with the occurrence of schistosomiasis mansoni. The generated risk maps of intermediate host snails might assist the national control programme for spatial targeting of control interventions and to ultimately move towards schistosomiasis elimination in Brazil.

Item Type: Article
Uncontrolled Keywords: Biomphalaria, intermediate host snail, schistosomiasis, risk Mapping and prediction, ecological niche model, maximum entropy, Brazil
Subjects: 600 Tecnologia - Scienze applicate > 610 Medicina e salute (Classificare qui la tecnologia dei servizi medici) > 616 Malattie (classificare qui la Clinica medica, la medicina basata sull'evidenza, la Medicina interna, la Medicina sperimentale) > 616.9 Altre malattie (altri rami della Medicina) > 616.96 Parassitosi, malattie causate da funghi (micosi) (classificare qui la Parassitologia medica) > 616.962 Endoparassitosi (classificare qui le opere d'insieme sulle malattie causate da vermi) (classificare qui l'Elmintologia medica)
Depositing User: Luca Tiberi
Date Deposited: 12 Sep 2019 09:50
Last Modified: 12 Sep 2019 09:50

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