title: A nationwide seroprevalence of total antibody to hepatitis A virus from 2005 to 2009: age and area-adjusted prevalence rates.
abstract: OBJECTIVE
  Recent outbreak of hepatitis A in Korea is clearly related to the epidemiological shift of hepatitis A virus (HAV). However, nationwide seroprevalence data have been limited. This study estimated the nationwide, age- and area-adjusted anti-HAV prevalence from 2005 to 2009.
  
  
  METHODS
  Retrospective analysis of the results of total anti-HAV test in 25,140 cases which were requested by 1,699 medical institutions throughout the nation to Seoul Clinical Laboratory from Jan. 1 2005 to Dec. 31 2009 was performed. The estimated seroprevalence was adjusted by area and age of the standard population based on the 2005 Census data from Korea National Statistical Office.
  
  
  RESULTS
  The area-adjusted anti-HAV prevalence in the children younger than 10 years were 33.4% in 2005 and 69.9% in 2009. The most susceptible age groups to HAV infection during the last 5 years were teenagers and the young adults in their age of twenties. The area-adjusted seroprevalence in 2009 were 11.9% in the age group of 20-29 years, 23.4% in the age group of 10-19 years, 48.4% in the age group of 30-39 years. The population in 40-49 years showed geographically different seroprevalence with the lowest rate in Seoul (80%).
  
  
  CONCLUSIONS
  The most susceptible age group to HAV infection is 10-29 years, while the young children less than 10 years showed about 70% seropositivity. The changing seroepidemiology should be monitored continuously for the proper vaccination and patient care.
authors.affiliation: Department of Internal Medicine, Seoul Saeroun Internal Medicine, Seoul, Korea.
authors.forename: Donghun
authors.initials: D
authors.lastname: Lee
authors.forename: Moran
authors.initials: M
authors.lastname: Ki
authors.forename: Anna
authors.initials: A
authors.lastname: Lee
authors.forename: Kyoung Ryul
authors.initials: KR
authors.lastname: Lee
authors.forename: Hee Bong
authors.initials: HB
authors.lastname: Park
authors.forename: Chang Sub
authors.initials: CS
authors.lastname: Kim
authors.forename: Bo Young
authors.initials: BY
authors.lastname: Yoon
authors.forename: Jong Hyun
authors.initials: JH
authors.lastname: Kim
authors.forename: Young Sok
authors.initials: YS
authors.lastname: Lee
authors.forename: Sook Hyang
authors.initials: SH
authors.lastname: Jeong
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D002648:Child; D002675:Child, Preschool; D005260:Female; D006506:Hepatitis A / Q000453:epidemiology*; D035922:Hepatitis A Antibodies / Q000097:blood*; D017957:Hepatitis A Virus, Human / Q000276:immunology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D016036:Seroepidemiologic Studies
chemical_list: D035922:Hepatitis A Antibodies