title: The yield of universal antibody to hepatitis B core antigen donor screening in the Netherlands, a hepatitis B virus low-endemic country.
abstract: BACKGROUND
  In the Netherlands, universal antibody to hepatitis B core antigen (anti-HBc) donor screening was introduced in July 2011 to intercept potentially infectious donations slipping through hepatitis B surface antigen (HBsAg) and hepatitis B virus (HBV) DNA minipool screening (HBV DNA MP6).
  
  
  METHODS
  The yield and donor loss were evaluated after the first 2 years of universal anti-HBc donor screening. A total of 382,173 donors were tested for anti-HBc and, if positive, for antibody to HBsAg (anti-HBs). Anti-HBc-reactive donors with anti-HBs of less than 200 IU/L were deferred, but repeat donors were allowed retesting after 6 months if anti-HBs was less than 10 IU/mL. Anti-HBc false positivity was estimated using the crude anti-HBc signal, family name-based ethnicity scoring, and donor follow-up.
  
  
  RESULTS
  Anti-HBc screening identified 13 confirmed or potential HBsAg- and HBV DNA MP6-negative recent HBV infections. In addition, 820 anti-HBc-reactive donors with low anti-HBs titers (<200 IU/mL), potentially harboring occult HBV infection (OBI), were identified and deferred. Overall, 1583 (0.41%) donors were deferred: 1178 (0.31%) during first-time anti-HBc screening, 361 (0.09%) anti-HBc seroconverters, and 44 (0.01%) donors with waning anti-HBs titers. Only 188 of 1583 (12%) deferred donors could be reentered upon retesting. Estimated anti-HBc false positivity was 16%, but varied greatly among anti-HBc-reactive donors with and without anti-HBs (8% vs. 62%).
  
  
  CONCLUSIONS
  Anti-HBc testing has improved the safety of the Dutch blood supply but its exact yield remains difficult to determine, due to the complexity of confirming anti-HBc reactivity and OBI. In a low-endemic country, donor loss associated with anti-HBc screening is sustainable, but adds to the already considerable list of donor exclusions.
authors.affiliation: Department of Blood-Borne Infections, Division of Research, Sanquin Blood Supply Foundation, Amsterdam, The Netherlands.|Department of Virology, Division of Diagnostics, Sanquin Blood Supply Foundation, Amsterdam, The Netherlands.
authors.forename: Thijs J
authors.initials: TJ
authors.lastname: van de Laar
authors.affiliation: Unit of Medical Donor Affairs, Division of Blood Bank, Sanquin Blood Supply Foundation, Amsterdam, The Netherlands.
authors.forename: Tanneke
authors.initials: T
authors.lastname: Marijt-van der Kreek
authors.affiliation: Department of Blood-Borne Infections, Division of Research, Sanquin Blood Supply Foundation, Amsterdam, The Netherlands.|Department of Virology, Division of Diagnostics, Sanquin Blood Supply Foundation, Amsterdam, The Netherlands.
authors.forename: Marijke W
authors.initials: MW
authors.lastname: Molenaar-de Backer
authors.affiliation: Department of Blood-Borne Infections, Division of Research, Sanquin Blood Supply Foundation, Amsterdam, The Netherlands.|Department of Virology, Division of Diagnostics, Sanquin Blood Supply Foundation, Amsterdam, The Netherlands.
authors.forename: Boris M
authors.initials: BM
authors.lastname: Hogema
authors.affiliation: Department of Blood-Borne Infections, Division of Research, Sanquin Blood Supply Foundation, Amsterdam, The Netherlands.|Department of Clinical Virology (CINIMA), Academic Medical Centre/University of Amsterdam, Amsterdam, The Netherlands.
authors.forename: Hans L
authors.initials: HL
authors.lastname: Zaaijer
mesh_terms: D000328:Adult; D058731:Blood Safety; D046148:Donor Selection; D005189:False Positive Reactions; D005260:Female; D006509:Hepatitis B / Q000097:blood / Q000453:epidemiology* / Q000635:transmission; D006510:Hepatitis B Antibodies / Q000097:blood*; D006512:Hepatitis B Core Antigens / Q000276:immunology*; D006514:Hepatitis B Surface Antigens / Q000097:blood; D006801:Humans; D008297:Male; D009426:Netherlands / Q000453:epidemiology; D021141:Nucleic Acid Amplification Techniques; D015995:Prevalence; D012367:RNA, Viral / Q000097:blood; D014766:Viremia / Q000097:blood / Q000453:epidemiology*
chemical_list: D006510:Hepatitis B Antibodies; D006512:Hepatitis B Core Antigens; D006514:Hepatitis B Surface Antigens; D012367:RNA, Viral