title: Weight-based policy of hepatitis B vaccination in very low birth weight infants in Taiwan: a retrospective cross-sectional study.
abstract: BACKGROUND
  The current recommendation of giving the first dose of hepatitis B vaccine to very low birth weight (VLBW) infants at 30 days of chronologic age usually is not practical, because most VLBW infants are not medically stable at that age. We use an alternative body-weight-based protocol, and evaluate its efficacy in an endemic area under a universal immunization program.
  
  
  METHODS
  The immunogenicity of the current hepatitis B vaccination strategy in 155 VLBW preterm infants was evaluated at age 2 to 13 years, with parental consent. All of the infants were born between 1995 and 2006, and received their first dose of hepatitis B vaccine when they reached 2,000-2,200 g, irrespective of chronological age. Hepatitis B immunoglobulin (HBIG) was given at birth to infants born to HBsAg(+)/HBeAg(+) mothers.
  
  
  RESULTS
  All 155 of the recruited children were HBsAg and anti-HBc negative. The anti-HBs seropositivity rate (geometric mean titer) was 84.1% (146.5 mIU/mL) for children under 3 years, 73.5% (68.8 mIU/mL) for 4- to 7-year-olds, 27.7% (55.4 mIU/mL) for 8- to 11-year-olds and 20% (6.0 mIU/mL) for children ≥12 years of age. More than 90% of these children received the first vaccination after 30 days of age, half (51%) at 60 to 90 days, and 29 children (18.6%) after 90 days of age. Of the 26 infants born to HBsAg(+) mothers, 6/6 infants of HBeAg(+) mothers received HBIG at birth, and 12/20 infants of HBeAg(-) mothers received HBIG. None of the 26 infants became infected.
  
  
  CONCLUSIONS
  Delaying hepatitis B vaccinations in VLBW preterm infants until they reach a weight of 2,000 g, with the administration of HBIG at birth for infants of HBsAg(+) mothers provided adequate immunogenicity and protection in a highly endemic area. Weight-based policy of hepatitis B vaccination is an effective and practical alternative strategy for VLBW infants.
authors.affiliation: Graduate Institute of Clinical Medicine, National Taiwan University College of Medicine, Taipei, Taiwan; Department of Pediatrics, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan.
authors.forename: Chien-Yi
authors.initials: CY
authors.lastname: Chen
authors.affiliation: Department of Pediatrics, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan.
authors.forename: Huey-Ling
authors.initials: HL
authors.lastname: Chen
authors.affiliation: Department of Pediatrics, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan.
authors.forename: Hung-Chieh
authors.initials: HC
authors.lastname: Chou
authors.affiliation: Department of Pediatrics, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan.
authors.forename: Po-Nien
authors.initials: PN
authors.lastname: Tsao
authors.affiliation: Department of Pediatrics, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan.
authors.forename: Wu-Shiun
authors.initials: WS
authors.lastname: Hsieh
authors.affiliation: Department of Pediatrics, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan.
authors.forename: Mei-Hwei
authors.initials: MH
authors.lastname: Chang
mesh_terms: D000293:Adolescent; D001835:Body Weight / Q000276:immunology*; D002353:Carrier State / Q000276:immunology; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D006291:Health Policy; D006509:Hepatitis B / Q000097:blood / Q000276:immunology* / Q000517:prevention & control*; D017325:Hepatitis B Vaccines / Q000276:immunology*; D006801:Humans; D007231:Infant, Newborn; D019102:Infant, Very Low Birth Weight / Q000276:immunology*; D008297:Male; D009035:Mothers; D012189:Retrospective Studies; D013624:Taiwan; D014611:Vaccination
chemical_list: D017325:Hepatitis B Vaccines