title: Epidemiological and genetic analysis of a sustained community-wide outbreak of hepatitis A in the Republic of Korea, 2008: a hospital-based case-control study.
abstract: BACKGROUND
  The epidemiological shift of hepatitis A has contributed to a sustained community-wide outbreak in Korea during 2008.
  
  
  OBJECTIVE
  To assess the risk factors associated with hepatitis A virus (HAV) propagation, and to analyze the circulating genotype in the sustained community-wide outbreak.
  
  
  METHODS
  The hospital-based case-control study was conducted in an 850-bed university hospital in Seoul from April to August, 2008. For molecular analysis of HAV isolates, a 488-bp gene fragment of the VP1 region was amplified and sequenced.
  
  
  RESULTS
  In the multivariated logistic regression model, the risk factors of HAV infection adjusted by age were contacts with hepatitis A case (OR 3.98, 95% CI: 1.36-11.66), residence with child aged <or=5 years (OR 3.43, 95% CI: 1.32-8.87), consuming uncooked lettuce (OR 3.98, 95% CI: 1.83-8.68) or carrot (OR 2.38, 95% CI: 2.38-5.09), drinking tap water (OR 3.68, 95% CI: 1.62-8.37) or portable spring water (OR 2.71, 95% CI: 1.11-6.62) supplied by water purifiers, and eating out (OR 3.87, 95% CI: 1.53-9.78). All isolates analyzed belonged to genotype IIIA. There were 42 nucleotide differences in the sequenced VP1 region among the isolates. Amino acid sequences were identical with each other.
  
  
  CONCLUSIONS
  Our study suggests that sporadically contaminated food- or water-borne sources as well as person-to-person transmission might lead a sustained community-wide HAV outbreak and pre-existing dominant genotype IA might be replaced with genotype IIIA as a major epidemic strain in Korea. Our findings urge the health authority to make public guidelines for HAV vaccination and outbreak control.
authors: Division of Infectious Diseases, Department of Internal Medicine, Korea University College of Medicine, Seoul, Republic of Korea.
authors: Young Kyung
authors: YK
authors: Yoon
authors: Byung Chul
authors: BC
authors: Chun
authors: Ha Kyung
authors: HK
authors: Lee
authors: Yeon Seok
authors: YS
authors: Seo
authors: Jung Ho
authors: JH
authors: Shin
authors: Yoon Sik
authors: YS
authors: Hong
authors: Hee Sun
authors: HS
authors: Sim
authors: Jeoung Yeon
authors: JY
authors: Kim
authors: Jeong Yeon
authors: JY
authors: Kim
authors: Yoon Seon
authors: YS
authors: Park
authors: Dae Won
authors: DW
authors: Park
authors: Jang Wook
authors: JW
authors: Sohn
authors: Min Ja
authors: MJ
authors: Kim
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D017714:Community-Acquired Infections / Q000453:epidemiology* / Q000821:virology; D004196:Disease Outbreaks; D005260:Female; D005516:Food Microbiology; D006506:Hepatitis A / Q000453:epidemiology* / Q000821:virology; D030041:Hepatitis A virus / Q000235:genetics*; D006761:Hospitals; D006801:Humans; D007723:Korea / Q000453:epidemiology; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D017720:Molecular Epidemiology / Q000379:methods; D015999:Multivariate Analysis; D010802:Phylogeny; D012307:Risk Factors; D015678:Viral Structural Proteins / Q000235:genetics; D014871:Water Microbiology
chemical_list: C096539:VP1 protein, hepatitis A virus; D015678:Viral Structural Proteins