title: Modeling and Validation of Environmental Suitability for Schistosomiasis Transmission Using Remote Sensing.
abstract: BACKGROUND
  Schistosomiasis is the most widespread water-based disease in sub-Saharan Africa. Transmission is governed by the spatial distribution of specific freshwater snails that act as intermediate hosts and human water contact patterns. Remote sensing data have been utilized for spatially explicit risk profiling of schistosomiasis. We investigated the potential of remote sensing to characterize habitat conditions of parasite and intermediate host snails and discuss the relevance for public health.
  
  
  METHODS
  We employed high-resolution remote sensing data, environmental field measurements, and ecological data to model environmental suitability for schistosomiasis-related parasite and snail species. The model was developed for Burkina Faso using a habitat suitability index (HSI). The plausibility of remote sensing habitat variables was validated using field measurements. The established model was transferred to different ecological settings in Côte d'Ivoire and validated against readily available survey data from school-aged children.
  
  
  RESULTS
  Environmental suitability for schistosomiasis transmission was spatially delineated and quantified by seven habitat variables derived from remote sensing data. The strengths and weaknesses highlighted by the plausibility analysis showed that temporal dynamic water and vegetation measures were particularly useful to model parasite and snail habitat suitability, whereas the measurement of water surface temperature and topographic variables did not perform appropriately. The transferability of the model showed significant relations between the HSI and infection prevalence in study sites of Côte d'Ivoire.
  
  
  CONCLUSIONS
  A predictive map of environmental suitability for schistosomiasis transmission can support measures to gain and sustain control. This is particularly relevant as emphasis is shifting from morbidity control to interrupting transmission. Further validation of our mechanistic model needs to be complemented by field data of parasite- and snail-related fitness. Our model provides a useful tool to monitor the development of new hotspots of potential schistosomiasis transmission based on regularly updated remote sensing data.
authors.affiliation: Department of Remote Sensing, Institute for Geography and Geology, University of Würzburg, Würzburg, Germany.|United Nations University-Institute for Environment and Human Security, Bonn, Germany.
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Walz
authors.affiliation: Department of Remote Sensing, Institute for Geography and Geology, University of Würzburg, Würzburg, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Wegmann
authors.affiliation: Department of Remote Sensing, Institute for Geography and Geology, University of Würzburg, Würzburg, Germany.|German Remote Sensing Data Centre, German Aerospace Centre, Oberpfaffenhofen, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Dech
authors.affiliation: Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland.|University of Basel, Basel, Switzerland.
authors.forename: Penelope
authors.initials: P
authors.lastname: Vounatsou
authors.affiliation: Institut de Recherche en Sciences de la Santé, Ouagadougou, Burkina Faso.
authors.forename: Jean-Noël
authors.initials: JN
authors.lastname: Poda
authors.affiliation: Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire.|Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire.
authors.forename: Eliézer K
authors.initials: EK
authors.lastname: N'Goran
authors.affiliation: Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland.|University of Basel, Basel, Switzerland.
authors.forename: Jürg
authors.initials: J
authors.lastname: Utzinger
authors.affiliation: Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland.|University of Basel, Basel, Switzerland.
authors.forename: Giovanna
authors.initials: G
authors.lastname: Raso
mesh_terms: D000293:Adolescent; D002050:Burkina Faso / Q000453:epidemiology; D002648:Child; D007560:Cote d'Ivoire / Q000453:epidemiology; D017753:Ecosystem; D004812:Epidemiologic Methods; D006801:Humans; D015233:Models, Statistical; D058998:Remote Sensing Technology / Q000379:methods*; D012552:Schistosomiasis / Q000453:epidemiology / Q000635:transmission*