title: Seroprevalence and potential risk factors for Helicobacter pylori infection in Brazilian children.
abstract: BACKGROUND
  Helicobacter pylori infection has been proved to be of great relevance to public health in unindustrialized countries, especially in low socioeconomic groups. Poor hygiene, deficient sanitation, and crowded conditions have been reported as risk factors for this infection. In this work, we investigated whether social and demographic characteristics were associated with anti-H. pylori IgG antibodies in 1104 children aged 4-11 years old from Salvador, a large city located in northeastern Brazil.
  
  
  METHODS
  Standardized questionnaires were used to obtain social, demographic, and environmental data for the studied population in two periods of time (from 1997 to 2003 and in 2005). Anti-H. pylori IgG antibodies were assessed by indirect enzyme-linked immunosorbent assay in 2005.
  
  
  RESULTS
  Anti-H. pylori IgG antibody was present in 28.7% of the children. Among the studied variables, the following were positively associated with the presence of anti-H. pylori antibodies in multivariable analyses: age above 8 years old (OR = 1.72, 95% CI = 1.23-2.40), a larger sibling number (OR = 1.66, 95% CI = 1.26-2.18), nursery attendance (OR = 1.49, 95% CI = 1.04-2.12), location of the house at an unpaved street (OR = 2.03, 95% CI = 1.44-2.87) and absence of a flush toilet (OR = 1.32, 95% CI = 1.00-1.74).
  
  
  CONCLUSIONS
  Our data show that H. pylori infection in children from a major Brazilian city is associated with variables indicative of a crowded environment and deficient sanitation/habitation conditions, leading to the conclusion that improvements in hygiene and social conditions may protect children against this infection.
authors.affiliation: Health Science Institute, Federal University of Bahia, Bahia, Brazil.
authors.forename: Vitor Camilo Cavalcante
authors.initials: VC
authors.lastname: Dattoli
authors.forename: Rafael Valente
authors.initials: RV
authors.lastname: Veiga
authors.forename: Sergio Souza
authors.initials: SS
authors.lastname: da Cunha
authors.forename: Lain Carlos
authors.initials: LC
authors.lastname: Pontes-de-Carvalho
authors.forename: Maurício Lima
authors.initials: ML
authors.lastname: Barreto
authors.forename: Neuza Maria
authors.initials: NM
authors.lastname: Alcântara-Neves
mesh_terms: D000907:Antibodies, Bacterial / Q000097:blood; D001938:Brazil / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D005260:Female; D016481:Helicobacter Infections / Q000097:blood / Q000453:epidemiology* / Q000276:immunology*; D016480:Helicobacter pylori / Q000276:immunology; D006801:Humans; D006920:Hygiene; D007074:Immunoglobulin G / Q000097:blood; D008297:Male; D011446:Prospective Studies; D012307:Risk Factors; D016036:Seroepidemiologic Studies; D012959:Socioeconomic Factors
chemical_list: D000907:Antibodies, Bacterial; D007074:Immunoglobulin G