title: Use of wild bird surveillance, human case data and GIS spatial analysis for predicting spatial distributions of West Nile virus in Greece.
abstract: West Nile Virus (WNV) is the causative agent of a vector-borne, zoonotic disease with a worldwide distribution. Recent expansion and introduction of WNV into new areas, including southern Europe, has been associated with severe disease in humans and equids, and has increased concerns regarding the need to prevent and control future WNV outbreaks. Since 2010, 524 confirmed human cases of the disease have been reported in Greece with greater than 10% mortality. Infected mosquitoes, wild birds, equids, and chickens have been detected and associated with human disease. The aim of our study was to establish a monitoring system with wild birds and reported human cases data using Geographical Information System (GIS). Potential distribution of WNV was modelled by combining wild bird serological surveillance data with environmental factors (e.g. elevation, slope, land use, vegetation density, temperature, precipitation indices, and population density). Local factors including areas of low altitude and proximity to water were important predictors of appearance of both human and wild bird cases (Odds Ratio = 1,001 95%CI = 0,723-1,386). Using GIS analysis, the identified risk factors were applied across Greece identifying the northern part of Greece (Macedonia, Thrace) western Greece and a number of Greek islands as being at highest risk of future outbreaks. The results of the analysis were evaluated and confirmed using the 161 reported human cases of the 2012 outbreak predicting correctly (Odds = 130/31 = 4,194 95%CI = 2,841-6,189) and more areas were identified for potential dispersion in the following years. Our approach verified that WNV risk can be modelled in a fast cost-effective way indicating high risk areas where prevention measures should be implemented in order to reduce the disease incidence.
authors.affiliation: Faculty of Veterinary Medicine, University of Thessaly, Karditsa, Greece; Department of Biomedicine, Institute for Research and Technology of Thessaly, Centre For Research and Technology Hellas, Larissa, Greece.
authors.forename: George
authors.initials: G
authors.lastname: Valiakos
authors.affiliation: Faculty of Veterinary Medicine, University of Thessaly, Karditsa, Greece; Research Division, Hunting Federation of Macedonia and Thrace, Thessaloniki, Greece.
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Papaspyropoulos
authors.affiliation: Faculty of Veterinary Medicine, University of Thessaly, Karditsa, Greece.
authors.forename: Alexios
authors.initials: A
authors.lastname: Giannakopoulos
authors.affiliation: Technological Education Institute of Thessaly, Larissa, Greece.
authors.forename: Periklis
authors.initials: P
authors.lastname: Birtsas
authors.affiliation: Hellenic Center for Disease Control and Prevention (HCDCP) Ministry of Health, Athens, Greece; National and Kapodistrian University of Athens, Faculty of Medicine, Athens, Greece.
authors.forename: Sotirios
authors.initials: S
authors.lastname: Tsiodras
authors.affiliation: Disease Systems, SRUC, Edinburgh, United Kingdom.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Hutchings
authors.affiliation: Technological Education Institute of Thessaly, Larissa, Greece.
authors.forename: Vassiliki
authors.initials: V
authors.lastname: Spyrou
authors.affiliation: Hellenic Center for Disease Control and Prevention (HCDCP) Ministry of Health, Athens, Greece.
authors.forename: Danai
authors.initials: D
authors.lastname: Pervanidou
authors.affiliation: Faculty of Veterinary Medicine, University of Thessaly, Karditsa, Greece.
authors.forename: Labrini V
authors.initials: LV
authors.lastname: Athanasiou
authors.affiliation: Department of Agriculture Crop Production and Rural Environment, University of Thessaly, Volos, Greece.
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Papadopoulos
authors.affiliation: Faculty of Veterinary Medicine, University of Thessaly, Karditsa, Greece.
authors.forename: Constantina
authors.initials: C
authors.lastname: Tsokana
authors.affiliation: Hellenic Center for Disease Control and Prevention (HCDCP) Ministry of Health, Athens, Greece.
authors.forename: Agoritsa
authors.initials: A
authors.lastname: Baka
authors.affiliation: Faculty of Veterinary Medicine, University of Thessaly, Karditsa, Greece.
authors.forename: Katerina
authors.initials: K
authors.lastname: Manolakou
authors.affiliation: Faculty of Veterinary Medicine, University of Thessaly, Karditsa, Greece.
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Chatzopoulos
authors.affiliation: University of Lyon, VetAgro Sup, France.
authors.forename: Marc
authors.initials: M
authors.lastname: Artois
authors.affiliation: School of Veterinary Medicine & Science, University of Nottingham, Nottingham, United Kingdom.
authors.forename: Lisa
authors.initials: L
authors.lastname: Yon
authors.affiliation: School of Veterinary Medicine & Science, University of Nottingham, Nottingham, United Kingdom.
authors.forename: Duncan
authors.initials: D
authors.lastname: Hannant
authors.affiliation: Animal Health and Veterinary Laboratories Agency - Weybridge, United Kingdom.
authors.forename: Liljana
authors.initials: L
authors.lastname: Petrovska
authors.affiliation: Faculty of Medicine, University of Thessaly, Larissa, Greece.
authors.forename: Christos
authors.initials: C
authors.lastname: Hadjichristodoulou
authors.affiliation: Faculty of Veterinary Medicine, University of Thessaly, Karditsa, Greece; Department of Biomedicine, Institute for Research and Technology of Thessaly, Centre For Research and Technology Hellas, Larissa, Greece.
authors.forename: Charalambos
authors.initials: C
authors.lastname: Billinis
mesh_terms: D000818:Animals; D000835:Animals, Wild; D001717:Birds / Q000821:virology*; D002645:Chickens / Q000821:virology; D009033:Culicidae / Q000821:virology; D005260:Female; D040362:Geographic Information Systems; D006115:Greece; D006801:Humans; D011156:Population Density; D014901:West Nile Fever / Q000453:epidemiology* / Q000635:transmission* / Q000821:virology; D014902:West Nile virus / Q000302:isolation & purification* / Q000472:pathogenicity