title: Impact of individual-donation nucleic acid testing on risk of human immunodeficiency virus, hepatitis B virus, and hepatitis C virus transmission by blood transfusion in South Africa.
abstract: BACKGROUND
  In 2005, the South African National Blood Service introduced individual-donation (ID) nucleic acid test (NAT) screening for human immunodeficiency virus (HIV) RNA, hepatitis C virus (HCV) RNA, and hepatitis B virus (HBV) DNA. At the same time the use of ethnic origin to prioritize the transfusion of blood according to a hierarchy of residual risk was discontinued.
  
  
  METHODS
  ID-NAT (Ultrio on Procleix Tigris, Chiron) and serology (PRISM, Abbott) repeat test and confirmation testing algorithms were designed to enable differentiation between false-positive and true-NAT and -serology yields. After 1 year, the NAT and serology yield rates in first-time, lapsed, and repeat donors were analyzed and used to estimate the residual risk of HIV, HBV, and HCV infections by blood transfusion.
  
  
  RESULTS
  The HIV, HBV, and HCV ID-NAT window phase yield rates in 732,250 blood donations were 1:45,765, 1:11,810, and 1:732,200, respectively. Seven of 16 HIV window phase donations with viral loads above 16,000 copies/mL were HIV p24 antigen enzyme-linked immunosorbent assay positive. PRISM detected anti-HIV and hepatitis B surface antigen (HBsAg) in 89.4 and 73.9% of early infections in repeat donors. The Procleix assay detected viremia in 99.7 and 95.5% of anti-HIV- and HBsAg-positive first-time donors. In these donors, the occult HBV DNA carrier rate was 1:5200. The residual transmission risk of ID-NAT HIV, HBV, and HCV window phase donations was estimated at 1:479,000, 1:61,500, and 1:21,000,000 respectively.
  
  
  CONCLUSIONS
  One-year ID-NAT screening of 732,250 donations interdicted 16 HIV, 20 HBV, and 1 HCV window phase donations and 42 anti-hepatitis B core antigen-reactive infections during an early recovery or a later stage of occult HBV infection.
authors.affiliation: South African National Blood Service (SANBS), Roodepoort, South Africa.
authors.forename: Marion
authors.initials: M
authors.lastname: Vermeulen
authors.forename: Nico
authors.initials: N
authors.lastname: Lelie
authors.forename: Wendy
authors.initials: W
authors.lastname: Sykes
authors.forename: Robert
authors.initials: R
authors.lastname: Crookes
authors.forename: Johanna
authors.initials: J
authors.lastname: Swanevelder
authors.forename: Lilian
authors.initials: L
authors.lastname: Gaggia
authors.forename: Martin
authors.initials: M
authors.lastname: Le Roux
authors.forename: Eben
authors.initials: E
authors.lastname: Kuun
authors.forename: Sam
authors.initials: S
authors.lastname: Gulube
authors.forename: Ravi
authors.initials: R
authors.lastname: Reddy
mesh_terms: D001782:Blood Donors; D004279:DNA, Viral / Q000097:blood*; D015658:HIV Infections / Q000453:epidemiology / Q000635:transmission*; D006509:Hepatitis B / Q000453:epidemiology / Q000635:transmission*; D006514:Hepatitis B Surface Antigens / Q000097:blood; D006526:Hepatitis C / Q000453:epidemiology / Q000635:transmission*; D006801:Humans; D015995:Prevalence; D012367:RNA, Viral / Q000097:blood*; D012306:Risk; D013019:South Africa; D065227:Transfusion Reaction
chemical_list: D004279:DNA, Viral; D006514:Hepatitis B Surface Antigens; D012367:RNA, Viral