title: Immuno-prophylaxis of babies borne to hepatitis B carrier mothers.
abstract: OBJECTIVE
  To examine the efficacy of current hepatitis B immuno-prophylaxis and estimate the prevalence of S-mutant infections among local newborn babies.
  
  
  METHODS
  Prospective study.
  
  
  METHODS
  Regional hospital, Hong Kong.
  
  
  METHODS
  A total of 137 newborn babies delivered between the period of November 2000 and 30 June 2001 inclusive, whose mothers were chronic hepatitis B surface antigen carriers.
  
  
  RESULTS
  Of the 121 infants who were followed up for 12 months, three were found to be chronic hepatitis B virus carriers, giving a vertical transmission rate of 2.5%. One (0.8%) was suspected to be infected by the S-mutant. All the three hepatitis B virus carrier babies were born to mothers with hepatitis B e antigen, but none to the eight mothers suspected to have S-mutants. Of 119 (98.3%) infants who developed hepatitis B surface antibody upon follow-up at 12 months, 35 were found to have hepatitis B e antigen at birth. All were born to hepatitis B e antigen-positive mothers. Only three of the 35 babies were found to be hepatitis B virus carriers. Most babies lost the hepatitis B e antigen by 6 months of age; only the infected babies had the antigen persisting at 1 year of age. The non-infected infants' hepatitis B e antigen is likely transplacental.
  
  
  CONCLUSIONS
  Our hepatitis B virus prophylaxis programme was effective at preventing perinatal infection and the non-infected infants' hepatitis B e antigen was likely transplacental.
authors.affiliation: Department of Paediatrics and Adolescent Medicine, Tuen Mun Hospital, Tsing Chung Koon Road, Tuen Mun, Hong Kong.
authors.forename: K
authors.initials: K
authors.lastname: Tse
authors.forename: S L Y
authors.initials: SL
authors.lastname: Siu
authors.forename: K T
authors.initials: KT
authors.lastname: Yip
authors.forename: S M
authors.initials: SM
authors.lastname: Chan
authors.forename: T L
authors.initials: TL
authors.lastname: Que
authors.forename: W Y S
authors.initials: WY
authors.lastname: Lui
authors.forename: P S
authors.initials: PS
authors.lastname: Chan
mesh_terms: D002353:Carrier State; D005260:Female; D006509:Hepatitis B / Q000517:prevention & control*; D006511:Hepatitis B Antigens / Q000032:analysis; D017325:Hepatitis B Vaccines; D006513:Hepatitis B e Antigens / Q000032:analysis; D006515:Hepatitis B virus / Q000235:genetics; D006801:Humans; D007231:Infant, Newborn; D018445:Infectious Disease Transmission, Vertical / Q000517:prevention & control; D008431:Maternal-Fetal Exchange; D009154:Mutation; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious; D011446:Prospective Studies
chemical_list: D006511:Hepatitis B Antigens; D017325:Hepatitis B Vaccines; D006513:Hepatitis B e Antigens