title: Seroprevalence of hepatitis B virus among adults at high risk for HIV transmission two decades after implementation of nationwide hepatitis B virus vaccination program in Taiwan.
abstract: BACKGROUND
  Seroprevalence of hepatitis B virus (HBV) after implementation of universal neonatal HBV vaccination and catch-up vaccination programs remains rarely investigated among the adults who were born in the vaccination era (in or after 1986) and engaged in high-risk sexual behaviors.
  
  
  METHODS
  Between 2006 and 2012, we determined HBV surface antigen ([HBsAg), anti-HBs, and HBV core antibody (anti-HBc), hepatitis C virus antibody (anti-HCV) and rapid plasma reagin titers among HIV-infected men who have sex with men (MSM) born during 1984-1985 (Group I: 244 persons) and those born in or after 1986 (Group II: 523), and HIV-uninfected MSM (Group III: 377) and heterosexuals (Group IV: 217) born in or after 1986. Prevalence and incidence of HBV infection were estimated and multivariate analysis was performed to identify factors associated with HBsAg positivity.
  
  
  RESULTS
  Compared with Group I, Groups II-IV had a significantly lower prevalence of HBsAg positivity (7.8% vs 3.7%, 2.4%, and 3.2%, respectively); and the prevalence of anti-HBc positivity was also lower for Groups III and IV (30.3% vs. 19.6%, and 18.0%, respectively), but no difference was observed between Groups I and II (30.3% vs. 26.3%). In multivariate analysis, HBsAg positivity was significantly associated with syphilis (adjusted odds ratio, 2.990; 95% confidence interval, 1.502-5.953) and anti-HCV positivity (adjusted odds ratio, 3.402; 95% confidence interval, 1.091-10.614). In subjects of Group II with all-negative HBV markers at baseline, the incidence rate of HBsAg seroconversion was 0.486 episodes per 100 person-years; and for those who received combination antiretroviral therapy containing lamivudine and/or tenofovir, none developed HBsAg seroconversion during the follow-up.
  
  
  CONCLUSIONS
  Among the adults who were born in or after 1986 and engaged in high-risk sexual behaviors in Taiwan, neonatal HBV vaccination and catch-up vaccination programs conferred long-term protection against HBsAg seroconversion and HBsAg positivity was associated with syphilis and anti-HCV positivity.
authors.affiliation: Department of Internal Medicine, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan.
authors.forename: Hsin-Yun
authors.initials: HY
authors.lastname: Sun
authors.affiliation: Department of Internal Medicine, Tao-Yuan General Hospital, Ministry of Health and Welfare, Tao-Yuan, Taiwan.
authors.forename: Chien-Yu
authors.initials: CY
authors.lastname: Cheng
authors.affiliation: Department of Internal Medicine, National Cheng Kung University Hospital and College of Medicine, Tainan, Taiwan.
authors.forename: Nan-Yao
authors.initials: NY
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Far Eastern Memorial Hospital, New Taipei City, Taiwan.
authors.forename: Chia-Jui
authors.initials: CJ
authors.lastname: Yang
authors.affiliation: Department of Medicine, E-Da Hospital/I-Shou University, Kaohsiung, Taiwan.
authors.forename: Shiou-Haur
authors.initials: SH
authors.lastname: Liang
authors.affiliation: Department of Internal Medicine, Far Eastern Memorial Hospital, New Taipei City, Taiwan.
authors.forename: Mao-Song
authors.initials: MS
authors.lastname: Tsai
authors.affiliation: Department of Internal Medicine, National Cheng Kung University Hospital and College of Medicine, Tainan, Taiwan.
authors.forename: Wen-Chien
authors.initials: WC
authors.lastname: Ko
authors.affiliation: Department of Internal Medicine, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan.
authors.forename: Wen-Chun
authors.initials: WC
authors.lastname: Liu
authors.affiliation: Center for Infection Control, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Pei-Ying
authors.initials: PY
authors.lastname: Wu
authors.affiliation: Department of Internal Medicine, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan.
authors.forename: Cheng-Hsin
authors.initials: CH
authors.lastname: Wu
authors.affiliation: Department of Medicine, E-Da Hospital/I-Shou University, Kaohsiung, Taiwan.
authors.forename: Hsi-Hsun
authors.initials: HH
authors.lastname: Lin
authors.affiliation: Department of Internal Medicine, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan ; Department of Medical Research, China Medical University Hospital, Taichung, Taiwan ; China Medical University, Taichung, Taiwan.
authors.forename: Chien-Ching
authors.initials: CC
authors.lastname: Hung
mesh_terms: D000328:Adult; D000914:Antibodies, Viral / Q000276:immunology; D002908:Chronic Disease / Q000453:epidemiology / Q000517:prevention & control; D005260:Female; D015658:HIV Infections / Q000150:complications / Q000635:transmission*; D006509:Hepatitis B / Q000150:complications / Q000453:epidemiology* / Q000517:prevention & control*; D006514:Hepatitis B Surface Antigens / Q000276:immunology; D006515:Hepatitis B virus / Q000276:immunology / Q000502:physiology*; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D012306:Risk; D016036:Seroepidemiologic Studies; D013587:Syphilis / Q000150:complications; D013624:Taiwan / Q000453:epidemiology; D014611:Vaccination
chemical_list: D000914:Antibodies, Viral; D006514:Hepatitis B Surface Antigens