title: Prevalence of the newly described human circovirus, TTV, in United States blood donors.
abstract: BACKGROUND
  A novel nonenveloped single-stranded circular DNA virus (TTV) was recently identified. The prevalence of TTV in blood donors in the United States is, however, still unclear.
  
  
  METHODS
  Viral DNA was detected in US blood donors from five cities by using two sets of TTV primers: NG059/NG061/NG063 primers, which amplified the conserved region of strains 1 and 2, and T801/T935 primers, which amplified the 5' end region of the TTV sequence. A TTV antibody assay system was based on the detection of the truncated open reading frame (ORF)-1 (amino acids 1-411) from type 1b. The truncated ORF-1 was expressed as a fusion protein in Escherichia coli, and the fusion protein was used as the antigen in the antibody assay system.
  
  
  RESULTS
  Viremia was detected in 21 (8. 4%) of 250 donors by use of NG059/NG061/NG063 primers and 104 (41. 6%) of 250 by use of T801/T935 primers. There was little correlation among the assays, which suggests the preferential detection of different strains with the different primers. TTV antibody was detected in 38 of 100 donors: 32 (84%) of 38 with concurrent TTV viremia and 6 (16%) of 38 without TTV viremia. TTV viremia and/or TTV antibody-positive samples were detected in 52 (52%) of 100 of US blood donors.
  
  
  CONCLUSIONS
  Evidence of infection or exposure to TTV appears to be common among blood donors in United States.
authors.affiliation: Hematology Branch, National Heart, Lung, and Blood Institute, NIH, Bethesda, MD 20892, USA. handaa@nih.gov
authors.forename: A
authors.initials: A
authors.lastname: Handa
authors.forename: B
authors.initials: B
authors.lastname: Dickstein
authors.forename: N S
authors.initials: NS
authors.lastname: Young
authors.forename: K E
authors.initials: KE
authors.lastname: Brown
mesh_terms: D000914:Antibodies, Viral / Q000097:blood; D001769:Blood / Q000821:virology; D001782:Blood Donors / Q000706:statistics & numerical data; D004267:DNA Viruses / Q000276:immunology / Q000302:isolation & purification; D004279:DNA, Viral / Q000235:genetics; D014644:Genetic Variation; D006801:Humans; D015337:Multicenter Studies as Topic; D016133:Polymerase Chain Reaction; D015995:Prevalence; D017422:Sequence Analysis, DNA; D012984:Software; D014481:United States / Q000453:epidemiology
chemical_list: D000914:Antibodies, Viral; D004279:DNA, Viral