title: Changes in the seroprevalence of IgG anti-hepatitis A virus between 2001 and 2013: experience at a single center in Korea.
abstract: OBJECTIVE
  The incidence of symptomatic hepatitis A reportedly increased among 20- to 40-year-old Korean during the late 2000s. Vaccination against hepatitis A was commenced in the late 1990s and was extended to children aged <10 years. In the present study we analyzed the changes in the seroprevalence of IgG anti-hepatitis A virus (HAV) over the past 13 years.
  
  
  METHODS
  Overall, 4903 subjects who visited our hospital between January 2001 and December 2013 were studied. The seroprevalence of IgG anti-HAV was analyzed according to age and sex. In addition, the seroprevalence of IgG anti-HAV was compared among 12 age groups and among the following time periods: early 2000s (2001-2003), mid-to-late 2000s (2006-2008), and early 2010s (2011-2013). The chi-square test for trend was used for statistical analysis.
  
  
  RESULTS
  The seroprevalence of IgG anti-HAV did not differ significantly between the sexes. Furthermore, compared to the seroprevalence of IgG anti-HAV in the early 2000s and mid-to-late 2000s, that in the early 2010s was markedly increased among individuals aged 1-14 years and decreased among those aged 25-44 years (P<0.01). We also found that the seroprevalence of IgG anti-HAV in individuals aged 25-44 years in the early 2010s was lower than that in the early 2000s and mid-to-late 2000s.
  
  
  CONCLUSIONS
  The number of symptomatic HAV infection cases in Korea is decreasing, but the seroprevalence of IgG anti-HAV is low in the active population.
authors.affiliation: Department of Internal Medicine, Hanyang University Guri Hospital, Hanyang University College of Medicine, Guri, Korea.
authors.forename: Sung Jun
authors.initials: SJ
authors.lastname: Chung
authors.affiliation: Department of Internal Medicine, Hanyang University Guri Hospital, Hanyang University College of Medicine, Guri, Korea.
authors.forename: Tae Yeob
authors.initials: TY
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Hanyang University Guri Hospital, Hanyang University College of Medicine, Guri, Korea.
authors.forename: Sun Min
authors.initials: SM
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Hanyang University Guri Hospital, Hanyang University College of Medicine, Guri, Korea.
authors.forename: Min
authors.initials: M
authors.lastname: Roh
authors.affiliation: Department of Internal Medicine, Hanyang University Guri Hospital, Hanyang University College of Medicine, Guri, Korea.
authors.forename: Mi Yeon
authors.initials: MY
authors.lastname: Yu
authors.affiliation: Department of Internal Medicine, Hanyang University Guri Hospital, Hanyang University College of Medicine, Guri, Korea.
authors.forename: Jung Hoon
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Hanyang University Guri Hospital, Hanyang University College of Medicine, Guri, Korea.
authors.forename: ChangKyo
authors.initials: C
authors.lastname: Oh
authors.affiliation: Department of Internal Medicine, Hanyang University Guri Hospital, Hanyang University College of Medicine, Guri, Korea.
authors.forename: Eun Young
authors.initials: EY
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Hanyang University Guri Hospital, Hanyang University College of Medicine, Guri, Korea.
authors.forename: Seung
authors.initials: S
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Hanyang University Guri Hospital, Hanyang University College of Medicine, Guri, Korea.
authors.forename: Yong Cheol
authors.initials: YC
authors.lastname: Jeon
authors.affiliation: Department of Internal Medicine, Hanyang University Guri Hospital, Hanyang University College of Medicine, Guri, Korea.
authors.forename: Kyo-Sang
authors.initials: KS
authors.lastname: Yoo
authors.affiliation: Department of Internal Medicine, Hanyang University Guri Hospital, Hanyang University College of Medicine, Guri, Korea.
authors.forename: Joo Hyun
authors.initials: JH
authors.lastname: Sohn
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D005260:Female; D006506:Hepatitis A / Q000175:diagnosis / Q000453:epidemiology*; D035922:Hepatitis A Antibodies / Q000032:analysis*; D030041:Hepatitis A virus / Q000276:immunology*; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis*; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D056910:Republic of Korea; D016036:Seroepidemiologic Studies; D012737:Sex Factors; D055815:Young Adult
chemical_list: D035922:Hepatitis A Antibodies; D007074:Immunoglobulin G
keywords: Hepatitis A virus; IgG Anti-HAV; Seroprevalence