C F De Oliveira

Publications (2)5.46 Total impact

• Article: Surveillance of HIV-1 genetic subtypesand diversity in the US blood supply.

  C F de Oliveira, R S Diaz, D M Machado, M T Sullivan, T Finlayson, M Gwinn, E M Lackritz, A E Williams, D Kessler, E A Operskalski, J W Mosley, M P Busch
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  ABSTRACT: Recent reports of variant (non-subtype B) HIV infections in US populations have raised concerns about the sensitivity of subtype B virus-based donor screening and diagnostic assays. This study was designed to determine the prevalence and genetic diversity of HIV subtypes in US blood donors over the last two decades. Three groups were studied: hemophiliacs infected by clotting factor concentrates in the early 1980s (n = 49), blood donors retrospectively identified as being seropositive in 1985 (n = 97), and blood donors identified as seropositive between 1993 and 1996 (n = 405). Subtype assignment was based primarily on heteroduplex mobility analysis (HMA) of HIV-1 env, with DNA sequence confirmation of selected specimens. HIV peptide-based EIA serotyping was used to rule out HIV-2 and group O infections and to serotype HMA-refractory specimens. Of 551 specimens, 535 (97%) were assigned subtypes; 532 (99%) of these were subtype B. Three postscreening donations (1%) were assigned non-B subtypes (2 A, 1 C). Two of these three donors were born in Africa; the third was born in the United States and reported no risk factors other than heterosexual activity. HMA distribution plots showed an increase in env diversity among HIV-1 group B strains over time. The results support the need for continued surveillance of HIV subtype diversity and ongoing validation of the sensitivity of HIV diagnostic assays to non-B subtype infections.
  Transfusion 12/2000; 40(11):1399-406. · 3.22 Impact Factor
• Article: HIV type 1 tat gene heteroduplex mobility assay as a tool to establish epidemiologic relationships among HIV type 1-infected individuals.

  R S Diaz, C F De Oliveira, R Pardini, E Operskalski, A J Mayer, M P Busch
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  ABSTRACT: Molecular biology techniques are increasingly used to study the molecular epidemiology of infectious diseases. Most of these methods are expensive and labor-intensive. The human immunodeficiency virus (HIV) has substantial genomic variation, such that HIVs from different individuals are genetically diverse, although mutation rates differ for distinct regions of the genome. Most studies of HIV linkage and molecular evolution have focused on env or gag regions. We show that heteroduplex mobility analysis of the first exon of the HIV tat gene provides a simple, rapid, inexpensive, and reliable discriminatory tool for the molecular differentiation of shared versus distinct HIV-1 quasispecies when epidemiologic relations need to be defined. tat, as a relatively conserved region, appears to be a better region than the more variable env region to establish HIV-1 epidemiological linkages.
  AIDS Research and Human Retroviruses 10/1999; 15(13):1151-6. · 2.25 Impact Factor