Spatial distribution of the risk of dengue fever in southeast Brazil, 2006-2007

BMC Public Health

Research Article

John C Brown¹  Ana CN Mafra²  Luciana B Nucci²  Celso Stephan²  Ricardo Cordeiro²  Maria R Donalisio²  Valmir R Andrade³ 

[1] Department of Geography, University of Kansas, Lawrence, KS, USA;Department of Social and Preventive Medicine, School of Medical Sciences, State University of Campinas, São Paulo, Brazil;State Health Department of São Paulo - Superintendence for Control of Endemic Diseases SUCEN, Campinas, São Paulo, Brazil;

关键词: Dengue Fever;    Generalize Additive Model;    Larva Density;    Garbage Collection;    Dengue Infection;   

DOI  :  10.1186/1471-2458-11-355

 received in 2010-10-18, accepted in 2011-05-20,  发布年份 2011

来源: Springer

【 摘 要 】

BackgroundMany factors have been associated with circulation of the dengue fever virus and vector, although the dynamics of transmission are not yet fully understood. The aim of this work is to estimate the spatial distribution of the risk of dengue fever in an area of continuous dengue occurrence.MethodsThis is a spatial population-based case-control study that analyzed 538 cases and 727 controls in one district of the municipality of Campinas, São Paulo, Brazil, from 2006-2007, considering socio-demographic, ecological, case severity, and household infestation variables. Information was collected by in-home interviews and inspection of living conditions in and around the homes studied. Cases were classified as mild or severe according to clinical data, and they were compared with controls through a multinomial logistic model. A generalized additive model was used in order to include space in a non-parametric fashion with cubic smoothing splines.ResultsVariables associated with increased incidence of all dengue cases in the multiple binomial regression model were: higher larval density (odds ratio (OR) = 2.3 (95%CI: 2.0-2.7)), reports of mosquito bites during the day (OR = 1.8 (95%CI: 1.4-2.4)), the practice of water storage at home (OR = 2.5 (95%CI: 1.4, 4.3)), low frequency of garbage collection (OR = 2.6 (95%CI: 1.6-4.5)) and lack of basic sanitation (OR = 2.9 (95%CI: 1.8-4.9)). Staying at home during the day was protective against the disease (OR = 0.5 (95%CI: 0.3-0.6)). When cases were analyzed by categories (mild and severe) in the multinomial model, age and number of breeding sites more than 10 were significant only for the occurrence of severe cases (OR = 0.97, (95%CI: 0.96-0.99) and OR = 2.1 (95%CI: 1.2-3.5), respectively. Spatial distribution of risks of mild and severe dengue fever differed from each other in the 2006/2007 epidemic, in the study area.ConclusionsAge and presence of more than 10 breeding sites were significant only for severe cases. Other predictors of mild and severe cases were similar in the multiple models. The analyses of multinomial models and spatial distribution maps of dengue fever probabilities suggest an area-specific epidemic with varying clinical and demographic characteristics.

【 授权许可】

Unknown   
© Cordeiro et al; licensee BioMed Central Ltd. 2011. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.