title: Leptospirosis in Rio Grande do Sul, Brazil: An Ecosystem Approach in the Animal-Human Interface.
abstract: BACKGROUND
  Leptospirosis is an epidemic-prone neglected disease that affects humans and animals, mostly in vulnerable populations. The One Health approach is a recommended strategy to identify drivers of the disease and plan for its prevention and control. In that context, the aim of this study was to analyze the distribution of human cases of leptospirosis in the State of Rio Grande do Sul, Brazil, and to explore possible drivers. Additionally, it sought to provide further evidence to support interventions and to identify hypotheses for new research at the human-animal-ecosystem interface.
  
  
  RESULTS
  The risk for human infection was described in relation to environmental, socioeconomic, and livestock variables. This ecological study used aggregated data by municipality (all 496). Data were extracted from secondary, publicly available sources. Thematic maps were constructed and univariate analysis performed for all variables. Negative binomial regression was used for multivariable statistical analysis of leptospirosis cases. An annual average of 428 human cases of leptospirosis was reported in the state from 2008 to 2012. The cumulative incidence in rural populations was eight times higher than in urban populations. Variables significantly associated with leptospirosis cases in the final model were: Parana/Paraiba ecoregion (RR: 2.25; CI95%: 2.03-2.49); Neossolo Litolítico soil (RR: 1.93; CI95%: 1.26-2.96); and, to a lesser extent, the production of tobacco (RR: 1.10; CI95%: 1.09-1.11) and rice (RR: 1.003; CI95%: 1.002-1.04).
  
  
  CONCLUSIONS
  Urban cases were concentrated in the capital and rural cases in a specific ecoregion. The major drivers identified in this study were related to environmental and production processes that are permanent features of the state. This study contributes to the basic knowledge on leptospirosis distribution and drivers in the state and encourages a comprehensive approach to address the disease in the animal-human-ecosystem interface.
authors.affiliation: Department of Communicable Diseases and Health Analysis, Pan American Health Organization, Washington, D.C., United States of America.
authors.forename: Maria Cristina
authors.initials: MC
authors.lastname: Schneider
authors.affiliation: Department of Communicable Diseases and Health Analysis, Pan American Health Organization, Washington, D.C., United States of America.
authors.forename: Patricia
authors.initials: P
authors.lastname: Najera
authors.affiliation: Laboratório de Referência Nacional para Leptospirose, Centro Colaborador da Organização Mundial da Saúde, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil.
authors.forename: Martha M
authors.initials: MM
authors.lastname: Pereira
authors.affiliation: Faculdade de Medicina Veterinária, Departamento de Medicina Veterinária Preventiva, Laboratório de Epidemiologia Veterinária, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.
authors.forename: Gustavo
authors.initials: G
authors.lastname: Machado
authors.affiliation: Secretaria de Saúde do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.
authors.forename: Celso B
authors.initials: CB
authors.lastname: dos Anjos
authors.affiliation: Instituto de Pesquisas Veterinárias Desidério Finamor (IPVDF), Fundacão Estadual de Pesquisa Agropecuária (FEPAGRO), Eldorado do Sul, Rio Grande do Sul, Brazil.
authors.forename: Rogério O
authors.initials: RO
authors.lastname: Rodrigues
authors.affiliation: Secretaria da Agricultura Pecuária do Sul, Porto Alegre, Rio Grande do Sul, Brazil.
authors.forename: Gabriela M
authors.initials: GM
authors.lastname: Cavagni
authors.affiliation: Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis, Minnesota, United States of America.
authors.forename: Claudia
authors.initials: C
authors.lastname: Muñoz-Zanzi
authors.affiliation: Faculdade de Medicina Veterinária, Departamento de Medicina Veterinária Preventiva, Laboratório de Epidemiologia Veterinária, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.
authors.forename: Luis G
authors.initials: LG
authors.lastname: Corbellini
authors.affiliation: Department of Communicable Diseases and Health Analysis, Pan American Health Organization, Washington, D.C., United States of America.
authors.forename: Mariana
authors.initials: M
authors.lastname: Leone
authors.affiliation: Laboratório de Avaliação e Promoção da Saúde Ambiental, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil.
authors.forename: Daniel F
authors.initials: DF
authors.lastname: Buss
authors.affiliation: Department of Communicable Diseases and Health Analysis, Pan American Health Organization, Washington, D.C., United States of America.
authors.forename: Sylvain
authors.initials: S
authors.lastname: Aldighieri
authors.affiliation: Department of Communicable Diseases and Health Analysis, Pan American Health Organization, Washington, D.C., United States of America.
authors.forename: Marcos A
authors.initials: MA
authors.lastname: Espinal
mesh_terms: D001938:Brazil / Q000453:epidemiology; D017753:Ecosystem; D004781:Environmental Exposure; D006801:Humans; D015994:Incidence; D007922:Leptospirosis / Q000453:epidemiology*; D016273:Occupational Exposure; D012307:Risk Factors; D012424:Rural Population; D012959:Socioeconomic Factors; D014505:Urban Population