Possible risk factors for the transmission of hepatitis E virus and for the severe form of hepatitis E acquired locally in Hokkaido, Japan

J Med Virol. 2005 Jul;76(3):341-9. doi: 10.1002/jmv.20364.


Hepatitis E in industrialized countries has not been well studied. To define the possible risk factors for transmission of hepatitis E virus (HEV) and for the severe form of hepatitis E in Japan, we investigated the clinical and virological characteristics of hepatitis E in 32 patients who contracted the mild (n=23) or severe form (n=9) of domestically acquired hepatitis E between 1996 and 2004 in Hokkaido, where hepatitis E is most prevalent in Japan. Nine patients with the severe form of hepatitis E included two patients with fulminant hepatitis E and seven patients who were diagnosed with severe acute hepatitis in which hepatic encephalopathy did not appear during the course of the illness despite low plasma prothrombin activity (<or=40%) and/or increased total bilirubin level (>or=20 mg/dl). At least 25 patients (78%) had consumed uncooked or undercooked pig liver and/or intestine 1-2 months before the onset of hepatitis E. When compared with the seven patients with HEV genotype 3, the 25 patients with HEV genotype 4 had a higher peak alanine aminotransferase (ALT) level (P=0.0338) and a lower level of lowest prothrombin activity (P=0.0340). The severe form of hepatitis E was associated with the presence of an underlying disease (56% [5/9] vs. 17% [4/23], P=0.0454). The study suggests that zoonotic food-borne transmission of HEV plays an important role in the occurrence of hepatitis E in Hokkaido, Japan, and that the HEV genotype and the presence of an underlying disease influence the severity of hepatitis E.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Alanine Transaminase / blood
  • Animals
  • Base Sequence
  • Bilirubin / blood
  • DNA, Viral / chemistry
  • Feeding Behavior
  • Female
  • Genotype
  • Hepatic Encephalopathy / complications
  • Hepatitis E / complications
  • Hepatitis E / transmission*
  • Hepatitis E / virology*
  • Hepatitis E virus / classification
  • Hepatitis E virus / genetics
  • Hepatitis E virus / isolation & purification
  • Humans
  • Japan
  • Male
  • Middle Aged
  • Molecular Sequence Data
  • Phylogeny
  • Prothrombin / analysis
  • Risk Factors
  • Swine
  • Zoonoses


  • DNA, Viral
  • Prothrombin
  • Alanine Transaminase
  • Bilirubin

Associated data

  • GENBANK/AB194282
  • GENBANK/AB194283
  • GENBANK/AB194284
  • GENBANK/AB194285
  • GENBANK/AB194286
  • GENBANK/AB194287
  • GENBANK/AB194288
  • GENBANK/AB194289
  • GENBANK/AB194290
  • GENBANK/AB194291
  • GENBANK/AB194292
  • GENBANK/AB194293
  • GENBANK/AB194294
  • GENBANK/AB194295
  • GENBANK/AB194296
  • GENBANK/AB194297
  • GENBANK/AB194298
  • GENBANK/AB194299