title: Younger siblings play a major role in Helicobacter pylori transmission among children from a low-income community in the Northeast of Brazil.
abstract: OBJECTIVE
  To further evaluate intrafamilial transmission of H. pylori infection during childhood, we investigated the prevalence of H. pylori in family members from a poor H. pylori high-prevalence urban community in the Northeast of Brazil.
  
  
  METHODS
  H. pylori infection was investigated in 570 members of 128 households, by (13) C-urea breath test in children and by ELISA in mothers and other adult relatives.
  
  
  RESULTS
  The overall prevalence of H. pylori infection (376/570) increased with age (p < .001) and ranged from 28.9%, in children aged 6 months to 5 years, to 82% in adults over 40 years. An H. pylori positive mother and the number of infected siblings are independent risk factors for childhood H. pylori infection (OR = 2.2, 95% CI = 1.0-4.6 and OR = 4.3, 95% CI = 2.3-8.1, respectively) The number of siblings, number of younger siblings, and number of infected younger siblings were also associated with the infection in the univariate analysis. The number of infected younger siblings remained independently associated with the infection (p = .000), even after controlling for all the above cited variables, in addition to the H. pylori status of siblings and mothers, age, number of people per room, and number of children in the household.
  
  
  CONCLUSIONS
  The transmission of H. pylori occurs from infected mothers to their offspring and among siblings, notably from younger siblings to the older ones.
authors.affiliation: Clinical Research Unity - Department of Internal Medicine - University Hospital Walter Cantídio - Federal University of Ceará, Fortaleza, Ceará, Brazil.
authors.forename: André M N
authors.initials: AM
authors.lastname: Fialho
authors.forename: Andréa B C
authors.initials: AB
authors.lastname: Braga
authors.forename: Manuel B
authors.initials: MB
authors.lastname: Braga Neto
authors.forename: Jéssica G
authors.initials: JG
authors.lastname: Carneiro
authors.forename: Andreia M C
authors.initials: AM
authors.lastname: Rocha
authors.forename: Maria N
authors.initials: MN
authors.lastname: Rodrigues
authors.forename: Dulciene M M
authors.initials: DM
authors.lastname: Queiroz
authors.forename: Lúcia L B C
authors.initials: LL
authors.lastname: Braga
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000907:Antibodies, Bacterial / Q000097:blood; D001938:Brazil / Q000453:epidemiology; D001944:Breath Tests; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005192:Family Health; D005260:Female; D016481:Helicobacter Infections / Q000191:economics* / Q000453:epidemiology / Q000382:microbiology / Q000635:transmission*; D016480:Helicobacter pylori / Q000276:immunology / Q000302:isolation & purification* / Q000502:physiology; D006801:Humans; D007223:Infant; D008297:Male; D011203:Poverty; D012307:Risk Factors; D035781:Siblings; D055815:Young Adult
chemical_list: D000907:Antibodies, Bacterial