title: Is the prevalence of wheeze in children altered by neonatal BCG vaccination?
abstract: BACKGROUND
  The prevalence of asthma and atopic disease has increased in recent decades, but precise reasons for this increase are unknown. BCG vaccination is thought to be among a group of vaccines capable of manipulating the immune system toward T(H)1 dominance and therefore reducing the likelihood of atopic disease.
  
  
  OBJECTIVE
  The aim of this study was to determine the influence of neonatal BCG vaccination on the prevalence of wheeze in a large community population of children.
  
  
  METHODS
  In a historical cohort study, a parent-completed questionnaire was used to identify the prevalence of wheeze in BCG-vaccinated and nonvaccinated children in Manchester, England.
  
  
  RESULTS
  There were 2414 participants aged between 6 and 11 years. In a univariate analysis neonatal BCG vaccination was associated with a significantly lower prevalence of wheeze (odds ratio, 0.69; 95% CI, 0.55-0.86), and statistical significance was retained when the analysis was adjusted for potential confounders (odds ratio, 0.68; 95% CI, 0.53-0.87).
  
  
  CONCLUSIONS
  These results demonstrate an association between asthma symptom prevalence and neonatal BCG vaccination, relating to a possible 27% reduction in prevalence, and are therefore of considerable public health importance.
  
  
  CONCLUSIONS
  The capacity of neonatal BCG vaccination to reduce the prevalence of respiratory symptoms in children warrants further investigation.
authors: General Practice Research Unit, North West Lung Research Centre, Wythenshawe Hospital, Manchester. linehanmary@yahoo.co.uk
authors: Mary F
authors: MF
authors: Linehan
authors: Timothy L
authors: TL
authors: Frank
authors: Michelle L
authors: ML
authors: Hazell
authors: Helen C
authors: HC
authors: Francis
authors: Julie A
authors: JA
authors: Morris
authors: David N
authors: DN
authors: Baxter
authors: Robert M
authors: RM
authors: Niven
mesh_terms: D001249:Asthma / Q000453:epidemiology*; D001500:BCG Vaccine / Q000276:immunology*; D002648:Child; D015331:Cohort Studies; D006801:Humans; D007231:Infant, Newborn; D015995:Prevalence; D012135:Respiratory Sounds / Q000276:immunology*
chemical_list: D001500:BCG Vaccine