title: Geodemographics profiling of influenza A and B virus infections in community neighborhoods in Japan.
abstract: BACKGROUND
  The spread of influenza viruses in a community are influenced by several factors, but no reports have focused on the relationship between the incidence of influenza and characteristics of small neighborhoods in a community. We aimed to clarify the relationship between the incidence of influenza and neighborhood characteristics using GIS and identified the type of small areas where influenza occurs frequently or infrequently.
  
  
  METHODS
  Of the 19,077 registered influenza cases, we analyzed 11,437 influenza A and 5,193 influenza B cases that were diagnosed by the rapid antigen test in 66-86 medical facilities in Isahaya City, Japan, from 2004 to 2008. We used the commercial geodemographics dataset, Mosaic Japan to categorize and classify each neighborhood. Furthermore, we calculated the index value of influenza in crude and age adjusted rates to evaluate the incidence of influenza by Mosaic segmentation. Additional age structure analysis was performed to geodemographics segmentation to explore the relationship between influenza and family structure.
  
  
  RESULTS
  The observed number of influenza A and B patients in the neighborhoods where young couples with small children lived was approximately 10-40% higher than the expected number (p < 0.01) during all seasons. On the contrary, the number of patients in the neighborhoods of the aging society in a rural area was 20-50% lower than the expected number (p < 0.01) during all seasons. This tendency was consistent after age adjustment except in the case of influenza B, which lost significance in higher incidence areas, but the overall results indicated high transmission of influenza in areas where young families with children lived.
  
  
  CONCLUSIONS
  Our analysis indicated that the incidence of influenza A and B in neighborhood groups is related to the family structure, especially the presence of children in households. Simple statistical analysis of geodemographics data is an effective method to understand the differences in the incidence of influenza among neighborhood groups, and it provides a valuable basis for community strategies to control influenza.
authors.affiliation: Division of Public Health, Department of Infectious Disease Control and International Medicine, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan. yoshi@lit.osaka-cu.ac.jp
authors.forename: Yoshinari
authors.initials: Y
authors.lastname: Kimura
authors.forename: Reiko
authors.initials: R
authors.lastname: Saito
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Tsujimoto
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Ono
authors.forename: Tomoki
authors.initials: T
authors.lastname: Nakaya
authors.forename: Yugo
authors.initials: Y
authors.lastname: Shobugawa
authors.forename: Asami
authors.initials: A
authors.lastname: Sasaki
authors.forename: Taeko
authors.initials: T
authors.lastname: Oguma
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Suzuki
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D009980:Influenza A virus / Q000235:genetics / Q000302:isolation & purification*; D009981:Influenza B virus / Q000235:genetics / Q000302:isolation & purification*; D007251:Influenza, Human / Q000453:epidemiology* / Q000821:virology*; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D012111:Residence Characteristics / Q000706:statistics & numerical data; D012621:Seasons; D055815:Young Adult