title: Declining prevalence of hepatitis E antibodies among Danish blood donors.
abstract: BACKGROUND
  The increasing incidence of reported hepatitis E cases in Europe has focused attention on hepatitis E virus (HEV) and the risk of transfusion-transmitted hepatitis E. The aim of this study was to investigate the prevalence of antibodies to HEV (anti-HEV) among Danish blood donors in 2013 and to compare it to previous studies in Denmark. In addition we wanted to compare the relative reactivity of two different assays.
  
  
  METHODS
  Samples from 504 blood donors were collected and analyzed for anti-HEV with an in-house assay developed at the National Institutes of Health (NIH). In addition the samples were analyzed with the Wantai anti-HEV assay. Demographic information and possible HEV exposure was collected by self-administered questionnaire.
  
  
  RESULTS
  Using the NIH assay the prevalence of anti-HEV among Danish blood donors was 10.7% and with the Wantai assay the prevalence of anti-HEV was 19.8% (p < 0.001). In both cases the presence of anti-HEV was significantly correlated with increasing age. In addition, anti-HEV as measured by the Wantai test was significantly associated with contact with children (p = 0.01), but in multivariate analysis only age was associated with anti-HEV in both assays. By the NIH assay, the prevalence had declined from 20.6% in 2003 to 10.7% in 2013.
  
  
  CONCLUSIONS
  Anti-HEV prevalence had decreased by half among Danish blood donors over 10 years, but was still highly prevalent. The difference in reactivity of the two assays demonstrates the importance of using the same assay when comparing the anti-HEV prevalence in populations over time.
authors.affiliation: Department of Clinical Immunology, Odense University Hospital, Odense, Denmark.
authors.forename: Dorte K
authors.initials: DK
authors.lastname: Holm
authors.affiliation: Department of Infectious Diseases, Odense University Hospital, Odense, Denmark.
authors.forename: Belinda K
authors.initials: BK
authors.lastname: Moessner
authors.affiliation: Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland.
authors.forename: Ronald E
authors.initials: RE
authors.lastname: Engle
authors.affiliation: Department of Blood-Borne Infections, Sanquin Blood Supply Foundation, Amsterdam, the Netherlands.
authors.forename: Hans L
authors.initials: HL
authors.lastname: Zaaijer
authors.affiliation: Department of Clinical Immunology, Odense University Hospital, Odense, Denmark.
authors.forename: Jørgen
authors.initials: J
authors.lastname: Georgsen
authors.affiliation: Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland.
authors.forename: Robert H
authors.initials: RH
authors.lastname: Purcell
authors.affiliation: Department of Infectious Diseases, Odense University Hospital, Odense, Denmark.
authors.forename: Peer B
authors.initials: PB
authors.lastname: Christensen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001782:Blood Donors; D003718:Denmark / Q000453:epidemiology; D005260:Female; D006508:Hepatitis Antibodies / Q000097:blood*; D016751:Hepatitis E / Q000097:blood* / Q000453:epidemiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence
chemical_list: D006508:Hepatitis Antibodies