title: Helicobacter pylori infection in rural China: demographic, lifestyle and environmental factors.
abstract: BACKGROUND
  Although Helicobacter pylori is one of the most common human bacterial infections worldwide, its mode of transmission is unclear.
  
  
  METHODS
  To investigate possible associations between H. pylori infection and demographic, lifestyle, and environmental factors in a rural Chinese population, a cross-sectional survey was administered to 3288 adults (1994 seropositive, 1019 seronegative, 275 indeterminate) from 13 villages in Linqu County, Shandong Province, China.
  
  
  RESULTS
  Helicobacter pylori prevalence was elevated for: infrequent handwashing before meals (OR = 1.7, 95% CI: 1.0-3.0), crowding (i.e. sharing a bed with >2 people [OR = 2.3, 95% CI: 1.3-4.2]), washing/bathing in a pond or ditch (OR = 1.5, 95% CI: 1.0-2.4), and medium (OR = 1.6, 95% CI: 1.3-2.0) and low (OR = 2.3, 95% CI: 1.9-2.9) compared to high village education level, and reduced for never being married or divorced (OR = 0.4, 95% CI: 0.2-1.0). There was also a suggestion that source of drinking water, especially water from a shallow village well might be related to H. pylori seropositivity. There was no evidence of an association between H. pylori prevalence and alcohol or tobacco use, raw fruit and vegetable intake, or individual social class measures.
  
  
  CONCLUSIONS
  The results of this study suggest that person-to-person transmission is the most plausible route of H. pylori infection in this rural Chinese population, but waterborne exposures deserve further investigation.
authors.affiliation: Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA. BrownL@mail.nih.gov
authors.forename: Linda Morris
authors.initials: LM
authors.lastname: Brown
authors.forename: Terry L
authors.initials: TL
authors.lastname: Thomas
authors.forename: Jun-Ling
authors.initials: JL
authors.lastname: Ma
authors.forename: Yun-Sheng
authors.initials: YS
authors.lastname: Chang
authors.forename: Wei-cheng
authors.initials: WC
authors.lastname: You
authors.forename: Wei-dong
authors.initials: WD
authors.lastname: Liu
authors.forename: Lian
authors.initials: L
authors.lastname: Zhang
authors.forename: David
authors.initials: D
authors.lastname: Pee
authors.forename: Mitchell H
authors.initials: MH
authors.lastname: Gail
mesh_terms: D000328:Adult; D002681:China / Q000453:epidemiology; D003430:Cross-Sectional Studies; D003441:Crowding; D005260:Female; D016481:Helicobacter Infections / Q000453:epidemiology* / Q000517:prevention & control; D016480:Helicobacter pylori; D006801:Humans; D008019:Life Style; D016013:Likelihood Functions; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D012306:Risk; D012959:Socioeconomic Factors; D014881:Water Supply