title: Helicobacter pylori prevalence and CagA status among children in two counties of China with high and low risks of gastric cancer.
abstract: BACKGROUND
  Studies in adult populations in selected countries with widely varying rates of gastric cancer have shown a weak correlation between gastric cancer mortality rates and the prevalence of CagA+ strains of H. pylori. However, only limited data are available in ethnically homogenous populations with varying rates in the same region. METHODS; We compared the prevalence of H. pylori in general and of CagA+ strains in particular among children in Shandong Province, China in areas at high (Linqu County) and low risk (Cangshan County) of gastric cancer. H. pylori status among children aged 3 to 12 years was determined by 13C-UBT, and CagA status was determined by enzyme-linked immunosorbent assay (ELISA). Because of the difficulty in obtaining blood from young children aged 3 to 4 years and from some children aged 5 years, CagA status was determined among part of children 5 years old and children 6 to 12 years old. RESULTS; Among 98 children aged 3 to 12 years in Linqu, 68 (69.4%) was H. pylori-positive, as compared with 29 (28.7%) among 101 children in Cangshan. Among children positive for 13C-UBT, the proportion of the CagA+ strains were identified was 46 (88.5%) of 52 in Linqu and 13 (81.3%) of 16 in Cangshan, respectively.
  
  
  CONCLUSIONS
  The prevalence of H. pylori was nearly three times higher among children in Linqu than in Cangshan, which may contribute to the large differential in gastric cancer rates for two neighboring populations in Shandong Province.
authors.affiliation: National Cancer Institute, Bethesda, MD 20892-7244, USA.
authors.forename: W C
authors.initials: WC
authors.lastname: You
authors.forename: L
authors.initials: L
authors.lastname: Zhang
authors.forename: K F
authors.initials: KF
authors.lastname: Pan
authors.forename: J
authors.initials: J
authors.lastname: Jiang
authors.forename: Y S
authors.initials: YS
authors.lastname: Chang
authors.forename: G I
authors.initials: GI
authors.lastname: Perez-Perez
authors.forename: W D
authors.initials: WD
authors.lastname: Liu
authors.forename: J L
authors.initials: JL
authors.lastname: MA
authors.forename: M H
authors.initials: MH
authors.lastname: Gail
authors.forename: M J
authors.initials: MJ
authors.lastname: Blaser
authors.forename: J F
authors.initials: JF
authors.lastname: Fraumeni
authors.forename: G W
authors.initials: GW
authors.lastname: Xu
mesh_terms: D000907:Antibodies, Bacterial / Q000097:blood; D000942:Antigens, Bacterial / Q000097:blood*; D001426:Bacterial Proteins / Q000032:analysis*; D001944:Breath Tests / Q000379:methods; D002247:Carbon Isotopes; D002648:Child; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D016481:Helicobacter Infections / Q000175:diagnosis* / Q000453:epidemiology / Q000276:immunology; D016480:Helicobacter pylori / Q000276:immunology* / Q000472:pathogenicity*; D006801:Humans; D008297:Male; D015995:Prevalence; D012306:Risk; D013274:Stomach Neoplasms / Q000175:diagnosis / Q000276:immunology / Q000382:microbiology*; D014508:Urea / Q000032:analysis
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D002247:Carbon Isotopes; C080866:cagA protein, Helicobacter pylori; D014508:Urea