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

Abstract

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.

Spatial distribution of dengue incidence and socio-environmental conditions in Campinas, São Paulo State, Brazil, 2007

“…Since 1999, the ACCS in the southern region of the city showed high dengue incidence rates 25 . Although the epidemic in 2007 showed the highest incidence rates in Campinas as a whole, the precarious socio-environmental conditions in the southern region and the increased viral circulation in previous years (with a decrease in susceptibles) may be associated with the greater risk of the disease in children under 14 years.…”

“…The southern region of the city underwent recent urbanization, with squatting settlements, heavy population concentration, and precarious socioeconomic indicators and deficient urban infrastructure in terms of basic sanitation, garbage collection, intermittent water supply, etc. 25 .…”

Monitoring the Paraguayan epidemiological dengue surveillance system (2009-2011) using Benford’s law

“…Nevertheless, it is accepted that the proliferation of the vector increases when conditions are favorable to its reproduction (20,38,40), including socioeconomic conditions (39).…”

Sanitation-Related Behavior, Container Index, and Their Associations with Dengue Hemorrhagic Fever Incidence in Karanganyar, Central Java

“…Pengelolaan sampah yang buruk dapat menciptakan lingkungan berkembangbiak bagi nyamuk Aedes Aegypti. Hasil penelitian menunjukkan bahwa frekuensi pengelolaan pembuangan sampah kurang dari 1 kali per minggu meningkatkan kejadian DBD dan secara statistik signifikan (Bohra and Andrianasolo, 2001;Cordeiro et al, 2011;Suwannapong et al, 2014). Aji et al, (2016) Prastyowati (2013) menunjukkan bahwa jenis kontainer/wadah yang ditemukan mengandung larva Aedes Aegypti antara lain, dispenser, ember mandi yang berada diluar rumah, dan tempat penampungan air.…”