title: Use of the sensitive/less-sensitive (detuned) EIA strategy for targeting genetic analysis of HIV-1 to recently infected blood donors.
abstract: OBJECTIVE
  To corroborate the validity of the recently developed sensitive/less sensitive (S/LS) dual enzyme immunoassay (EIA) strategy for the detection of recently infected individuals and to genetically analyze recently transmitted strains of HIV-1 in a US blood donor population.
  
  
  METHODS
  The S/LS EIA strategy was used to identify 33 recently infected subjects among 281 enrolled HIV-1 seropositive blood donors (from a total of 410 HIV-1 infected subjects identified from 5 230 463 blood donations screened by participating US blood centers in 1995-1996).
  
  
  METHODS
  We analysed three host response and viral characteristics were associated with recent HIV-1 infection: rapidly increasing EIA optical density (OD) values, genetically homogeneous env gene quasispecies, and putative non-syncytium inducing env V3 loop sequences. The drug resistance genotypes of the recently transmitted strains were determined by DNA sequencing.
  
  
  RESULTS
  Increasing EIA OD values, clonal HIV-1 quasispecies and V3 loop sequences with inferred NSI phenotypes were generally detected in LS EIA non-reactive samples. Thirty-two subtype B and one CRF02_AG recombinant HIV-1 were detected. Genetic evidence for drug resistance to zidovudine (K70R) and non-nucleoside analog reverse transcriptase inhibitors (V108I) was detected in one strain each, and three other strains showed the presence of accessory protease inhibitor resistance mutations.
  
  
  CONCLUSIONS
  Immunologic and virologic results further substantiate the validity of the S/LS EIA strategy for the detection of recent infections and illustrate its use for targeting molecular and epidemiological investigations to incident cases identified from large cross-sectional screening programs, rather than the more costly and logistically difficult longitudinal studies.
authors.affiliation: Blood Centers of the Pacific, San Francisco, California 94118, USA.
authors.forename: Daisy M
authors.initials: DM
authors.lastname: Machado
authors.forename: Eric L
authors.initials: EL
authors.lastname: Delwart
authors.forename: Ricardo S
authors.initials: RS
authors.lastname: Diaz
authors.forename: Carlos F
authors.initials: CF
authors.lastname: de Oliveira
authors.forename: Katia
authors.initials: K
authors.lastname: Alves
authors.forename: Bhupat D
authors.initials: BD
authors.lastname: Rawal
authors.forename: Marian
authors.initials: M
authors.lastname: Sullivan
authors.forename: Marta
authors.initials: M
authors.lastname: Gwinn
authors.forename: Kenneth A
authors.initials: KA
authors.lastname: Clark
authors.forename: Michael P
authors.initials: MP
authors.lastname: Busch
mesh_terms: D015492:AIDS Serodiagnosis; D001782:Blood Donors; D004279:DNA, Viral / Q000032:analysis; D024882:Drug Resistance, Viral / Q000235:genetics; D005260:Female; D014644:Genetic Variation; D015483:HIV Antibodies / Q000097:blood*; D015658:HIV Infections / Q000175:diagnosis* / Q000453:epidemiology / Q000821:virology; D016333:HIV Protease / Q000235:genetics; D054303:HIV Reverse Transcriptase / Q000235:genetics; D015497:HIV-1 / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D020180:Heteroduplex Analysis; D006801:Humans; D007124:Immunoenzyme Techniques / Q000379:methods; D015994:Incidence; D008297:Male; D012680:Sensitivity and Specificity; D017422:Sequence Analysis, DNA
chemical_list: D004279:DNA, Viral; D015483:HIV Antibodies; D054303:HIV Reverse Transcriptase; D016333:HIV Protease