title: Impact of neonatal hepatitis B vaccination programme on age-specific prevalence of hepatitis B infection in teenage mothers in Hong Kong.
abstract: We examined the impact of the neonatal hepatitis B immunization programme, first provided to all neonates born to mothers screened positive for hepatitis B surface antigen (HBsAg) in late 1983, on the age-specific prevalence of HBsAg carriage in teenage mothers managed in 1998–2008. HBsAg carriage was found in 2.5%, 2.7%, 8.8% and 8.0% of mothers aged ≤ 16, 17, 18, and 19 years, respectively (P=0.004), which was also correlated with advancing age (P=0.011). While neither difference nor correlation with age was found in mothers born before 1984, the prevalence of 1.2%, 1.5%, 7.1% and 8.3%, respectively, was significantly different among (P=0.008) and correlated with (P=0.002) age in mothers born 1984 onwards. Regression analysis indicated there was a significantly higher incidence of HBsAg carriage from age 17 onwards (adjusted odds ratio 2.55, 95% confidence interval 1.07–6.10, P=0.035), suggesting that the protective effect of the vaccine declined in late adolescence.
authors.affiliation: Department of Obstetrics & Gynaecology, The Chinese University of Hong Kong and Prince of Wales Hospital, Shatin, Hong Kong, PRC. lao-tt@cuhk.edu.hk
authors.forename: T T
authors.initials: TT
authors.lastname: Lao
authors.forename: D S
authors.initials: DS
authors.lastname: Sahota
authors.forename: S S H
authors.initials: SS
authors.lastname: Suen
authors.forename: P K S
authors.initials: PK
authors.lastname: Chan
authors.forename: T Y
authors.initials: TY
authors.lastname: Leung
mesh_terms: D000293:Adolescent; D000367:Age Factors; D015331:Cohort Studies; D005260:Female; D006509:Hepatitis B / Q000097:blood / Q000453:epidemiology* / Q000517:prevention & control; D006514:Hepatitis B Surface Antigens / Q000097:blood; D017325:Hepatitis B Vaccines / Q000008:administration & dosage*; D006723:Hong Kong / Q000453:epidemiology; D006801:Humans; D007231:Infant, Newborn; D007232:Infant, Newborn, Diseases / Q000097:blood / Q000453:epidemiology* / Q000517:prevention & control / Q000821:virology; D009035:Mothers; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000097:blood / Q000453:epidemiology* / Q000821:virology; D015995:Prevalence; D012044:Regression Analysis
chemical_list: D006514:Hepatitis B Surface Antigens; D017325:Hepatitis B Vaccines