title: Changing hepatitis D virus epidemiology in a hepatitis B virus endemic area with a national vaccination program.
abstract: The emergence of hepatitis D virus (HDV) infection in the era of widespread HBV vaccination has not been described before. We aimed to investigate the changing epidemiology of HDV infection among high- and low-risk populations after an outbreak of human immunodeficiency virus (HIV) infection among injection drug users (IDUs) in Taiwan. A prospective, multicenter, cohort study of 2,562 hepatitis B surface antigen (HBsAg)-positive individuals was conducted to determine the prevalence, genotype, and risk factors of HDV infection from 2001 through 2012. The prevalence rates of HDV infection were 74.9%, 43.9%, 11.4%, 11.1%, and 4.4% among HIV-infected IDUs, HIV-uninfected IDUs, HIV-infected men who have sex with men, HIV-infected heterosexuals, and the general population of HBsAg-positive subjects, respectively. A significant increase in the trend of HDV prevalence from 38.5% to 89.8% was observed in HIV-infected IDUs (odds ratio = 3.06; 95% confidence interval: 1.68-5.56; P = 0.0002). In multivariate analysis, injection drug use, hepatitis C virus infection, HIV infection, serum HBsAg level ≧250 IU/mL, duration of drug use, and older age were significant factors associated with HDV infection. HDV genotype IV (72.2%) was the prevalent genotype circulating among IDUs, whereas genotype II was predominant in the non-IDU populations (73.3%). In the HIV cohort born after 1987 who were HBsAg negative, over half (52.9%) had antibody to hepatitis B surface antigen antibody levels of <10 mIU/mL and there was a significantly higher HBsAg seroprevalence in the HIV cohort, compared to the control group (8.1% vs. 0.0%; P = 0.02).
  
  
  CONCLUSIONS
  In the era of HBV vaccination, IDUs and HIV-infected individuals have emerged as high-risk groups and a reservoir for HDV infection. Effective strategies are needed to curb the reemerging epidemic of HDV infection in these high-risk groups.
authors: Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan.|Department of Medicine and Infection Control, E-Da Hospital/I-Shou University, Kaohsiung, Taiwan.
authors: Hsi-Hsun
authors: HH
authors: Lin
authors: School of Medicine, National Yang-Ming University, Taipei, Taiwan.|Department of Internal Medicine, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan.
authors: Susan Shin-Jung
authors: SS
authors: Lee
authors: Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors: Ming-Lung
authors: ML
authors: Yu
authors: Department of Internal Medicine, National Cheng Kung University Hospital, Tainan, Taiwan.|Department of Medicine, Medical College of National Cheng Kung University, Tainan, Taiwan.
authors: Ting-Tsung
authors: TT
authors: Chang
authors: Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan.|School of Medicine, National Yang-Ming University, Taipei, Taiwan.|Division of Gastroenterology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.
authors: Chien-Wei
authors: CW
authors: Su
authors: Section of Infectious Diseases, Taipei City Hospital, Taipei City Government, Taipei, Taiwan.
authors: Bor-Shen
authors: BS
authors: Hu
authors: Department of General Surgery, E-Da Hospital/I-Shou University, Kaohsiung, Taiwan.
authors: Yaw-Sen
authors: YS
authors: Chen
authors: Department of Medicine and Infection Control, E-Da Hospital/I-Shou University, Kaohsiung, Taiwan.
authors: Chun-Kai
authors: CK
authors: Huang
authors: Department of Medicine and Infection Control, E-Da Hospital/I-Shou University, Kaohsiung, Taiwan.
authors: Chung-Hsu
authors: CH
authors: Lai
authors: Department of Medicine and Infection Control, E-Da Hospital/I-Shou University, Kaohsiung, Taiwan.
authors: Jiun-Nong
authors: JN
authors: Lin
authors: Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan.|Translational Research Division, Medical Research Department, Taipei Veterans General Hospital, Taipei, Taiwan.
authors: Jaw-Ching
authors: JC
authors: Wu
mesh_terms: D000328:Adult; D000368:Aged; D060085:Coinfection; D055030:Drug Users / Q000706:statistics & numerical data*; D019353:Endemic Diseases / Q000517:prevention & control*; D005260:Female; D015658:HIV Infections / Q000821:virology*; D006509:Hepatitis B / Q000453:epidemiology* / Q000517:prevention & control; D017325:Hepatitis B Vaccines; D003699:Hepatitis D / Q000453:epidemiology*; D003698:Hepatitis Delta Virus / Q000235:genetics; D006801:Humans; D015994:Incidence; D008137:Longitudinal Studies; D008297:Male; D032541:Mass Vaccination; D008875:Middle Aged; D015999:Multivariate Analysis; D015995:Prevalence; D011446:Prospective Studies; D012307:Risk Factors; D013624:Taiwan / Q000453:epidemiology; D014766:Viremia / Q000453:epidemiology
chemical_list: D017325:Hepatitis B Vaccines