title: Hepatitis B (prevention).
abstract: BACKGROUND
  Nearly a third of the world's population has been infected by hepatitis B at some point, and at least 350 million people have become chronic carriers. Progressive liver damage occurs in up to 25% of carriers. In areas of high endemicity, transmission occurs largely in childhood, from an infected mother to her baby, or between members of a household.
  
  
  METHODS
  We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of vaccination against hepatitis B infection in countries with high endemicity; and in countries with low endemicity? We searched: Medline, Embase, The Cochrane Library and other important databases up to November 2006 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).
  
  
  RESULTS
  We found 46 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.
  
  
  CONCLUSIONS
  In this systematic review we present information relating to the effectiveness and safety of the following interventions: selective vaccination of high-risk individuals; selective vaccination of people with chronic liver disease not caused by hepatitis B; universal vaccination of adolescents; universal vaccination of infants.
authors.affiliation: St James Hospital, Dublin, Ireland.
authors.forename: Suzanne
authors.initials: S
authors.lastname: Norris
authors.forename: Abdul
authors.initials: A
authors.lastname: Mohsen
mesh_terms: D006509:Hepatitis B; D009035:Mothers; D014481:United States; D014486:United States Food and Drug Administration