title: Indigenous hepatitis E in England and wales from 2003 to 2012: evidence of an emerging novel phylotype of viruses.
abstract: BACKGROUND
  Enhanced surveillance and molecular characterisation studies of hepatitis E virus (HEV) in England and Wales have been undertaken since 2003. The dynamics of hepatitis E have changed recently with an increase in the number of indigenous cases and an observed viral shift.
  
  
  METHODS
  HEV antibody and RNA data were analysed to ascertain the annual number of acute infections, the HEV genotype disposition and viral phylogeny. These data were investigated in the context of collected travel history and demographic data.
  
  
  RESULTS
  In total, 2713 acute hepatitis E cases were diagnosed, of which 1376 were indigenous infections. Travel associated cases remained steady and mainly associated with Genotype 1 infections. In contrast, major fluctuations were noted in indigenously-acquired cases with a dramatic year on year increase during 2010-2012. Molecular characterisation demonstrated indigenous infections to cluster into two distinct phylogenetic groups with the emergence of a novel group of Genotype 3 viruses coinciding with the recent increase in cases.
  
  
  CONCLUSIONS
  HEV infection rates are dynamic in England and Wales, influenced by changing trends in indigenously-acquired cases. The recent increase in indigenous cases and the emergence of indigenous viruses not commonly circulating prior to 2010 suggest that the risk of acquiring HEV has changed.
authors.affiliation: Blood Borne Virus Unit, MS-Colindale, Public Health England, London NW9 5EQ, United Kingdom.
authors.forename: Samreen
authors.initials: S
authors.lastname: Ijaz
authors.forename: Bengü
authors.initials: B
authors.lastname: Said
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Boxall
authors.forename: Erasmus
authors.initials: E
authors.lastname: Smit
authors.forename: Dilys
authors.initials: D
authors.lastname: Morgan
authors.forename: Richard S
authors.initials: RS
authors.lastname: Tedder
mesh_terms: D000328:Adult; D003710:Demography; D004739:England / Q000453:epidemiology; D005260:Female; D005838:Genotype; D006508:Hepatitis Antibodies / Q000097:blood; D016751:Hepatitis E / Q000453:epidemiology* / Q000235:genetics; D016752:Hepatitis E virus / Q000235:genetics* / Q000276:immunology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010802:Phylogeny; D012367:RNA, Viral / Q000032:analysis; D017422:Sequence Analysis, DNA; D014195:Travel; D014852:Wales / Q000453:epidemiology
chemical_list: D006508:Hepatitis Antibodies; D012367:RNA, Viral
keywords: England and Wales; hepatitis E; indigenous; molecular characterisation; patient demography; phylogeny; surveillance