title: Serologic Responses After Hepatitis B Vaccination in Preterm Infants Born to Hepatitis B Surface Antigen-Positive Mothers: Singapore Experience.
abstract: The Advisory Committee on Immunization Practices (ACIP) recommends a 4-dose vaccination schedule for preterm low birth weight infants (<2 kg) and a 3-dose vaccination schedule for preterm infants (≥2 kg) born to hepatitis B surface antigen (HBsAg)-positive mothers. However, data remain limited for these high-risk infants, and the optimal dosing schedule in Asia is not well established.
  
  
  
  The aim of this study was to evaluate the serologic vaccine responses in preterm infants born to HBsAg-positive mothers using current vaccination guidelines.
  
  
  
  Preterm babies of gestation less than 37 completed weeks born to HBsAg-positive mothers were prospectively recruited during 6 years (June 2009 to December 2015) and retrospectively recruited via convenience sampling in 2 years (June 2013 to April 2015) in 2 tertiary pediatric centers. The preterm infants were given 4 or 3 vaccine doses as per ACIP 2005 guidelines. Vaccine response was defined as achieving hepatitis B surface antibody values of >10 IU/L [Abbott Architect (Abbott Laboratories, Chicago, IL)] at 9 months of chronologic age.
  
  
  
  A total of 24 preterm infants were recruited. Four had a birth weight <2 kg. Of 23 surviving infants, all were negative for HBsAg. One baby (4.5%) did not achieve adequate vaccine response. All 4 infants with birth weight <2 kg achieved seroprotective values.
  
  
  
  The current ACIP-recommended vaccination schedule results in adequate antibody responses in preterm infants of HBsAg-positive mothers.
authors.affiliation: From the *Khoo Teck Puat-National University Children's Medical Institute, National University Health System, Singapore; †Department of Paediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; ‡Department of Neonatology, National University Health System, Singapore; §Department of Paediatrics, KK Women's and Children's Hospital, Singapore; ¶Laboratory Medicine, and ‖Department of Gastroenterology and Hepatology, National University Health System, Singapore; and **National Healthcare Group Polyclinics, Singapore.
authors.forename: Christelle Xian-Ting
authors.initials: CX
authors.lastname: Tan
authors.forename: Si-Min
authors.initials: SM
authors.lastname: Chan
authors.forename: Le-Ye
authors.initials: LY
authors.lastname: Lee
authors.forename: Christina
authors.initials: C
authors.lastname: Ong
authors.forename: Kong-Boo
authors.initials: KB
authors.lastname: Phua
authors.forename: Marion Margaret
authors.initials: MM
authors.lastname: Aw
authors.forename: Sharon
authors.initials: S
authors.lastname: Saw
authors.forename: Guan-Huei
authors.initials: GH
authors.lastname: Lee
authors.forename: Franco
authors.initials: F
authors.lastname: Wong
authors.forename: Koh-Cheng
authors.initials: KC
authors.lastname: Thoon
mesh_terms: D005260:Female; D006509:Hepatitis B / Q000276:immunology / Q000517:prevention & control / Q000821:virology; D006510:Hepatitis B Antibodies / Q000097:blood*; D006514:Hepatitis B Surface Antigens / Q000097:blood*; D017325:Hepatitis B Vaccines / Q000008:administration & dosage / Q000276:immunology; D006515:Hepatitis B virus / Q000276:immunology; D006801:Humans; D007231:Infant, Newborn; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000276:immunology / Q000821:virology; D011446:Prospective Studies; D012189:Retrospective Studies; D012846:Singapore
chemical_list: D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens; D017325:Hepatitis B Vaccines