title: Spatial heterogeneity of dengue fever in local studies, City of Niterói, Southeastern Brazil.
abstract: OBJECTIVE
  To analyze the spatial and temporal occurrence of dengue fever and its association with the heterogeneity of urban environment characteristics.
  
  
  METHODS
  A total of 1,212 dengue cases, recorded in the Information System for Notifiable Diseases (Sinan) between 1998 and 2006, in the city of Niterói, Southeastern Brazil, were georeferenced according to census tracts. These tracts were classified into homogeneous areas for the occurrence of the disease: slum, shipyard and urban area. Cases were grouped into five periods--two inter-epidemic periods (1998-2000 and 2003-2005) and three epidemic periods (2001, 2002 and 2006)--and analyzed using operations between layers in a geographic information system (GIS) environment. The kernel method was used to identify clusters of cases. Kulldorff's spatial scan statistic was used to confirm these clusters statistically.
  
  
  RESULTS
  Of all cases, 57% were females. Age groups with the highest number of cases were 20-29-years (20.5%) and 30-39-years (17.7%). The hill slum sector showed only 11% of households covered by garbage collection service, the highest percentage of illiterate individuals (8.7%) and head of families with income lower than one monthly minimum wage (29.5%). Cases remained in the slum sectors. In the first epidemic year and in the inter-epidemic periods, the highest number of cases was found in the hill and flatland slum sectors; in the second and third epidemic years, in the flatland slum sector.
  
  
  CONCLUSIONS
  The economically active portion of the population was that most affected in the study area. Census tracts show spatial heterogeneity in relation to life conditions. In addition, in some tracts, there are differences in spatial and temporal distribution of the risk of occurrence of dengue fever.
authors: Departamento de Epidemiologia e Bioestatística, Instituto de Saúde da Comunidade, Universidade Federal Fluminense, Av. Marquês de Paraná 303, Rio de Janeiro, RJ, Brazil. rflauzino@uol.com.br
authors: Regina Fernandes
authors: RF
authors: Flauzino
authors: Reinaldo
authors: R
authors: Souza-Santos
authors: Christovam
authors: C
authors: Barcelllos
authors: Renata
authors: R
authors: Gracie
authors: Mônica de Avelar Figueiredo Mafra
authors: Mde A
authors: Magalhães
authors: Rosely Magalhães de
authors: RM
authors: Oliveira
mesh_terms: D000328:Adult; D001938:Brazil / Q000453:epidemiology; D003715:Dengue / Q000453:epidemiology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008297:Male; D011204:Poverty Areas; D012959:Socioeconomic Factors; D013029:Space-Time Clustering; D013997:Time Factors; D014505:Urban Population / Q000145:classification / Q000706:statistics & numerical data*; D055815:Young Adult