title: High prevalences of hepatitis B and C virus infections among adults living in Binh Thuan province, Vietnam.
abstract: OBJECTIVE
  Vietnam is one of the countries with the highest mortality from liver cancer, which is mostly attributed to hepatitis B virus (HBV) and hepatitis C virus (HCV) infections. For planning preventive strategies against these infections, we investigated prevalences of HBV and HCV infections among adults living in Binh Thuan, Vietnam.
  
  
  METHODS
  Our study consisted of a serological survey for HBV and HCV infections and a questionnaire survey on their risk factors. The sample size was calculated based on anticipated rate of hepatitis B surface antigen (HBsAg). Subjects were randomly sampled using a multistage method. Confirmation and family-tree surveys were conducted to examine persistent HBV infection and intrafamilial HBV transmission, respectively.
  
  
  RESULTS
  A total of 509 adults, comprised of 230 men (45.2%) and 279 women (54.8%), were enrolled. Prevalences of HBsAg, hepatitis B surface antibody and hepatitis B core antibody were 15.3%, 60.3% and 71.7%, respectively. Most HBV DNA positive sera were classified as genotype B (75.3%) and C (11.7%). Of HBsAg positive subjects, 96.7% were persistently infected and one acutely HBV infected person was identified. Family-tree surveys suggested that horizontal extrafamilial HBV transmission might have been frequent. Prevalences of anti-HCV and HCV RNA were 3.3% and 1.8%, respectively. HCV genotype 6a was prominent (55.6%).
  
  
  CONCLUSIONS
  In Binh Thuan, prevalences of HBV and HCV infections are high, HBV genotype B and HCV genotype 6a are predominant, and horizontal HBV transmission may still occur. Therefore, raising the coverage of a universal HBV vaccination program may be an effective liver cancer control in Vietnam.
authors.affiliation: Department of Epidemiology, Infectious Disease Control and Prevention, Institute of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan; Department of Health, Binh Thuan Province, Phan Thiet City, Vietnam.
authors.forename: Son Huy
authors.initials: SH
authors.lastname: Do
authors.forename: Hiroko
authors.initials: H
authors.lastname: Yamada
authors.forename: Mayumi
authors.initials: M
authors.lastname: Fujimoto
authors.forename: Masayuki
authors.initials: M
authors.lastname: Ohisa
authors.forename: Junko
authors.initials: J
authors.lastname: Matsuo
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Akita
authors.forename: Keiko
authors.initials: K
authors.lastname: Katayama
authors.forename: Nhon
authors.initials: N
authors.lastname: Van Nguyen
authors.forename: Yuzo
authors.initials: Y
authors.lastname: Miyakawa
authors.forename: Junko
authors.initials: J
authors.lastname: Tanaka
keywords: Vietnam; general population; hepatitis B virus; hepatitis C virus; seroepidemiology