title: Modelling cholera epidemics: the role of waterways, human mobility and sanitation.
abstract: We investigate the role of human mobility as a driver for long-range spreading of cholera infections, which primarily propagate through hydrologically controlled ecological corridors. Our aim is to build a spatially explicit model of a disease epidemic, which is relevant to both social and scientific issues. We present a two-layer network model that accounts for the interplay between epidemiological dynamics, hydrological transport and long-distance dissemination of the pathogen Vibrio cholerae owing to host movement, described here by means of a gravity-model approach. We test our model against epidemiological data recorded during the extensive cholera outbreak occurred in the KwaZulu-Natal province of South Africa during 2000-2001. We show that long-range human movement is fundamental in quantifying otherwise unexplained inter-catchment transport of V. cholerae, thus playing a key role in the formation of regional patterns of cholera epidemics. We also show quantitatively how heterogeneously distributed drinking water supplies and sanitation conditions may affect large-scale cholera transmission, and analyse the effects of different sanitation policies.
authors.affiliation: Laboratory of Ecohydrology (ECHO), School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland. lorenzo.mari@epfl.ch
authors.forename: L
authors.initials: L
authors.lastname: Mari
authors.forename: E
authors.initials: E
authors.lastname: Bertuzzo
authors.forename: L
authors.initials: L
authors.lastname: Righetto
authors.forename: R
authors.initials: R
authors.lastname: Casagrandi
authors.forename: M
authors.initials: M
authors.lastname: Gatto
authors.forename: I
authors.initials: I
authors.lastname: Rodriguez-Iturbe
authors.forename: A
authors.initials: A
authors.lastname: Rinaldo
mesh_terms: D002771:Cholera / Q000453:epidemiology* / Q000635:transmission; D058872:Epidemics; D006801:Humans; D008962:Models, Theoretical; D011157:Population Dynamics; D012499:Sanitation; D013019:South Africa / Q000453:epidemiology; D014734:Vibrio cholerae; D014871:Water Microbiology