title: A nationwide survey for hepatitis E virus prevalence in Japanese blood donors with elevated alanine aminotransferase.
abstract: BACKGROUND
  Although we reported two cases of transfusion-transmitted hepatitis E in Japan, the prevalence of hepatitis E virus (HEV) in Japanese blood donors is not very clear.
  
  
  METHODS
  Blood samples of donors who were deferred from donation because of elevated alanine aminotransferase (ALT) levels were collected from all Japanese Red Cross Blood Centers and subjected to HEV tests.
  
  
  RESULTS
  Among the 41 donors with elevated ALT levels higher than 500 IU per L in Hokkaido, HEV RNA was detected in 8 (19.5%) samples. In 1389 donor samples with ALT levels of higher than 200 IU per L in nationwide Japan, the numbers of positive HEV RNA, immunoglobulin M (IgM) anti-HEV, and immunoglobulin G (IgG) anti-HEV samples were 15 (1.1%), 14 (1.0%), and 45 (3.2%), respectively. Although RNA-positive donors were predominantly male and found in any geographic area of Japan, they tended to be higher in number in eastern Japan including Hokkaido and lower in number in western Japan. Of the 23 HEV-positive samples, 19 were Genotype 3 and 4 were Genotype 4. DNA sequences of the 9 isolates showed more than 98.5 percent homology with the known swine HEV isolates. In 1062 donor samples with ALT levels of 61 to 199 IU per L, the percentages of IgM and IgG anti-HEV-positive samples were 0.1 and 2.7 percent, respectively, although there was no HEV RNA-positive sample.
  
  
  CONCLUSIONS
  HEV markers (HEV RNA and anti-HEV) were detected in donors with elevated ALT levels who were widely distributed over Japan. The prevalence and incidence were higher in eastern Japan than in western Japan.
authors.affiliation: Japanese Red Cross Hokkaido Blood Center, Sapporo, Japan.
authors.forename: Hidekatsu
authors.initials: H
authors.lastname: Sakata
authors.forename: Keiji
authors.initials: K
authors.lastname: Matsubayashi
authors.forename: Hiromi
authors.initials: H
authors.lastname: Takeda
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Sato
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Kato
authors.forename: Satoru
authors.initials: S
authors.lastname: Hino
authors.forename: Kenji
authors.initials: K
authors.lastname: Tadokoro
authors.forename: Hisami
authors.initials: H
authors.lastname: Ikeda
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000410:Alanine Transaminase / Q000378:metabolism*; D001782:Blood Donors / Q000706:statistics & numerical data*; D003625:Data Collection / Q000706:statistics & numerical data*; D005260:Female; D006508:Hepatitis Antibodies / Q000097:blood / Q000276:immunology; D016751:Hepatitis E / Q000097:blood / Q000201:enzymology* / Q000453:epidemiology* / Q000821:virology; D016752:Hepatitis E virus / Q000235:genetics; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D012367:RNA, Viral / Q000235:genetics
chemical_list: D006508:Hepatitis Antibodies; D012367:RNA, Viral; D000410:Alanine Transaminase