title: BCG vaccination and risk of atopy.
abstract: BACKGROUND
  It has been suggested that BCG vaccination may protect against development of allergic diseases, particularly when given just after birth. BCG vaccination was given routinely to all infants in Greenland until 1990, when it was withdrawn from the vaccination program. Whether this resulted in an increased prevalence of atopy in children born after the stop of BCG vaccination is unknown.
  
  
  OBJECTIVE
  To determine whether BCG vaccination and age at BCG vaccination are associated with development of atopy.
  
  
  METHODS
  Cross-sectional study among schoolchildren aged 8 to 16 years in 4 towns on the northwest coast of Greenland. Participants had a blood sample drawn and information on BCG vaccination was obtained during 2 periods, November 1998 and November 2001. A total of 1686 children (79% of available children) participated, 1575 of whom had complete information on vaccination status. Atopy was defined as a positive test result in an assay that tests for IgE specific against the most common inhalant allergens in serum.
  
  
  METHODS
  Odds ratio (OR) of atopy in BCG-vaccinated compared with unvaccinated children and OR according to age at vaccination.
  
  
  RESULTS
  The risk of atopy was the same in BCG-vaccinated compared with unvaccinated children after adjustment for confounders (OR, 1.03; 95% confidence interval, 0.72-1.48). The risk of atopy in BCG-vaccinated children was not associated with age at vaccination (P =.17).
  
  
  CONCLUSIONS
  BCG vaccination administered to infants is not associated with reduced risk of development of atopy.
authors.affiliation: Department of Epidemiology Research, Danish Epidemiology Science Centre, Statens Serum Institut, Artillerivej 5, DK 2300 Copenhagen S, Denmark. tgv@ssi.dk
authors.forename: Tyra G
authors.initials: TG
authors.lastname: Krause
authors.forename: Anders
authors.initials: A
authors.lastname: Hviid
authors.forename: Anders
authors.initials: A
authors.lastname: Koch
authors.forename: Jeppe
authors.initials: J
authors.lastname: Friborg
authors.forename: Thomas
authors.initials: T
authors.lastname: Hjuler
authors.forename: Jan
authors.initials: J
authors.lastname: Wohlfahrt
authors.forename: Ove Rosing
authors.initials: OR
authors.lastname: Olsen
authors.forename: Bjarne
authors.initials: B
authors.lastname: Kristensen
authors.forename: Mads
authors.initials: M
authors.lastname: Melbye
mesh_terms: D000293:Adolescent; D000367:Age Factors; D001500:BCG Vaccine / Q000276:immunology*; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D006116:Greenland / Q000453:epidemiology; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000453:epidemiology* / Q000276:immunology*; D007073:Immunoglobulin E / Q000097:blood; D007159:Immunologic Tests; D007231:Infant, Newborn; D008297:Male; D014611:Vaccination
chemical_list: D001500:BCG Vaccine; D007073:Immunoglobulin E