title: Detection of human immunodeficiency virus type 1 (HIV-1) RNA in pools of sera negative for antibodies to HIV-1 and HIV-2.
abstract: A total of 234 pools were prepared from 10,692 consecutive serum samples negative for antibodies to human immunodeficiency virus type 1 (HIV-1) and HIV-2 collected at five virological laboratories (average pool size, 45 serum samples). Pools were screened for the presence of HIV-1 RNA by a modified commercial assay (Amplicor HIV-1 Monitor test) which included an additional polyethylene glycol (PEG) precipitation step prior to purification of viral RNA (PEG Amplicor assay). The sensitivity of this assay for HIV-1 RNA detection in individual serum samples within pools matches that of standard commercial assays for individual serum samples, i.e., 500 HIV-1 RNA copies per ml. Five pools were identified as positive, and each one contained one antibody-negative, HIV-1 RNA-positive serum sample, corresponding to an average of 1 infected sample per 2,138 serum samples. Retrospective analysis revealed that the five HIV-1 RNA-positive specimens originated from individuals who had symptomatic primary HIV-1 infection at the time of sample collection and who were also positive for p24 antigenemia. We next assessed the possibility of performing the prepurification step by high-speed centrifugation (50,000 x g for 80 min) of 1.5-ml pools containing 25 microl of 60 individual serum samples, of which only 1 contained HIV-1 RNA (centrifugation Amplicor assay). The sensitivity of this assay also matches the sensitivities of standard commercial assays for HIV-1 RNA detection in individual serum samples. The results demonstrate that both assays with pooled sera can be applied to the screening of large numbers of serum samples in a time- and cost-efficient manner.
authors.affiliation: Laboratory of Virology and AIDS Center, Geneva University Hospital, Switzerland.
authors.forename: P A
authors.initials: PA
authors.lastname: Morandi
authors.forename: G A
authors.initials: GA
authors.lastname: Schockmel
authors.forename: S
authors.initials: S
authors.lastname: Yerly
authors.forename: P
authors.initials: P
authors.lastname: Burgisser
authors.forename: P
authors.initials: P
authors.lastname: Erb
authors.forename: L
authors.initials: L
authors.lastname: Matter
authors.forename: R
authors.initials: R
authors.lastname: Sitavanc
authors.forename: L
authors.initials: L
authors.lastname: Perrin
mesh_terms: D002498:Centrifugation; D011232:Chemical Precipitation; D005069:Evaluation Studies as Topic; D015483:HIV Antibodies / Q000097:blood; D015658:HIV Infections / Q000097:blood / Q000175:diagnosis*; D018023:HIV Seronegativity; D015497:HIV-1 / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification*; D015498:HIV-2 / Q000276:immunology; D006801:Humans; D011092:Polyethylene Glycols; D016133:Polymerase Chain Reaction / Q000379:methods; D012367:RNA, Viral / Q000097:blood*; D011933:Reagent Kits, Diagnostic; D012680:Sensitivity and Specificity
chemical_list: D015483:HIV Antibodies; D012367:RNA, Viral; D011933:Reagent Kits, Diagnostic; D011092:Polyethylene Glycols