title: Predicting the distribution of canine leishmaniasis in western Europe based on environmental variables.
abstract: The domestic dog is the reservoir host of Leishmania infantum, the causative agent of zoonotic visceral leishmaniasis endemic in Mediterranean Europe. Targeted control requires predictive risk maps of canine leishmaniasis (CanL), which are now explored. We databased 2187 published and unpublished surveys of CanL in southern Europe. A total of 947 western surveys met inclusion criteria for analysis, including serological identification of infection (504, 369 dogs tested 1971-2006). Seroprevalence was 23 2% overall (median 10%). Logistic regression models within a GIS framework identified the main environmental predictors of CanL seroprevalence in Portugal, Spain, France and Italy, or in France alone. A 10-fold cross-validation approach determined model capacity to predict point-values of seroprevalence and the correct seroprevalence class (<5%, 5-20%, >20%). Both the four-country and France-only models performed reasonably well for predicting correctly the <5% and >20% seroprevalence classes (AUC >0 70). However, the France-only model performed much better for France than the four-country model. The four-country model adequately predicted regions of CanL emergence in northern Italy (<5% seroprevalence). Both models poorly predicted intermediate point seroprevalences (5-20%) within regional foci, because surveys were biased towards known rural foci and Mediterranean bioclimates. Our recommendations for standardizing surveys would permit higher-resolution risk mapping.
authors.affiliation: Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK.
authors.forename: Ana O
authors.initials: AO
authors.lastname: Franco
authors.affiliation: Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK.
authors.forename: Clive R
authors.initials: CR
authors.lastname: Davies
authors.affiliation: Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK.
authors.forename: Adrian
authors.initials: A
authors.lastname: Mylne
authors.affiliation: Centre National de Référence des Leishmania, UMR MIVEGEC, Université Montpellier 1/Laboratoire de Parasitologie-Mycologie, CHU de Montpellier, Montpellier, France.
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Dedet
authors.affiliation: Laboratori de Parasitologia, Facultat de Farmàcia, Universitat de Barcelona, Barcelona, Spain.
authors.forename: Montserrat
authors.initials: M
authors.lastname: Gállego
authors.affiliation: Laboratori de Parasitologia, Facultat de Farmàcia, Universitat de Barcelona, Barcelona, Spain.
authors.forename: Cristina
authors.initials: C
authors.lastname: Ballart
authors.affiliation: Unit of Vector-borne Diseases and International Health, MIPI Department, Istituto Superiore di Sanità, Rome, Italy.
authors.forename: Marina
authors.initials: M
authors.lastname: Gramiccia
authors.affiliation: Unit of Vector-borne Diseases and International Health, MIPI Department, Istituto Superiore di Sanità, Rome, Italy.
authors.forename: Luigi
authors.initials: L
authors.lastname: Gradoni
authors.affiliation: Laboratorio de Referenda de Leishmaniasis, Servicio de Parasitología, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Madrid, Spain.
authors.forename: Ricardo
authors.initials: R
authors.lastname: Molina
authors.affiliation: Laboratorio de Referenda de Leishmaniasis, Servicio de Parasitología, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Madrid, Spain.
authors.forename: Rosa
authors.initials: R
authors.lastname: Gálvez
authors.affiliation: Departamento de Parasitología, Facultad de Farmacia, Universidad de Granada, Granada, Spain.
authors.forename: Francisco
authors.initials: F
authors.lastname: Morillas-Márquez
authors.affiliation: Departamento de Parasitología, Facultad de Farmacia, Universidad de Granada, Granada, Spain.
authors.forename: Sergio
authors.initials: S
authors.lastname: Barón-López
authors.affiliation: Unidade de Entomologia Médica/Unidade de Parasitologia e Microbiologia Médica, Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa, Lisbon, Portugal.
authors.forename: Carlos Alves
authors.initials: CA
authors.lastname: Pires
authors.affiliation: Unidade de Entomologia Médica/Unidade de Parasitologia e Microbiologia Médica, Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa, Lisbon, Portugal.
authors.forename: Maria Odete
authors.initials: MO
authors.lastname: Afonso
authors.affiliation: Department of Entomology, Natural History Museum, London, UK.
authors.forename: Paul D
authors.initials: PD
authors.lastname: Ready
authors.affiliation: Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Cox
mesh_terms: D000818:Animals; D004197:Disease Reservoirs; D004283:Dog Diseases / Q000453:epidemiology* / Q000469:parasitology; D004285:Dogs; D004777:Environment; D005060:Europe / Q000453:epidemiology; D005843:Geography; D007891:Leishmania / Q000276:immunology / Q000302:isolation & purification*; D007896:Leishmaniasis / Q000453:epidemiology / Q000469:parasitology / Q000662:veterinary*; D016015:Logistic Models; D016036:Seroepidemiologic Studies