CROI 2015 Program and Abstracts

Abstract Listing

Poster Abstracts

Figure 1: Recombination analyses of REC003 (Husband ; accession no KM438031) and REC024 (Wife; accession no KM438032) viruses Near full-length genomes of REC003 (9135bp; blue line) and REC024 (9176bp; dark line) were compared each other and with the closest strains of HIV-1 group M (suptype F2; green line) and HIV-1 group O (red line) identified by HIV BLAST. The viruses exhibit a mosaic structure M-O with the gag-pol portion belonging to HIV-1 M and the env portion belonging to HIV-1 O. Both viruses defined the same patterns along the entire genome. Conclusions: In this study, we observed for the first time that HIV-1 M/O intergroup recombinant viruses could be transmitted from one person to another. The genetic diversity and public health importance of transmitting these recombinant viruses in such areas where both viruses (HIV-1 groups M and O) are endemic cannot be overemphasized. 234 Searching for Rare HIV Strains in Rural Democratic Republic of Congo (2001–2003) Ana S. Vallari 1 ; Carole McArthur 2 ; Larry Sthreshley 3 ; Catherine Brennan 1 1 Abbott Laboratories, Chicago, IL, US; 2 University of Missouri–Kansas City, Kansas City, MO, US; 3 IMA World Health, Kinshasa, Congo (the Democratic Republic of the) Background: The Democratic Republic of Congo (DRC) is thought to be the epicenter of the HIV/AIDs pandemic. Not only were the oldest documented HIV-1 infections found in Kinshasa (circa 1959-1960) but the many diverse HIV-1 strains circulating in the DRC show high levels of intrasubtype diversity and intersubtype recombination indicative of an old epidemic. In this study, we characterized HIV strains in two rural areas of the DRC to identify and obtain sequences for rare subtypes and recombinants found only in the DRC. Methods: Specimens were collected, between 2001-2003, at the Vanga Hospital, Bandundu Province and The Good Shepard Hospital located 12 kilometers from Kananga, Kasia-Occidental Province in the DRC. A total of 264 HIV-infected specimens from voluntary testing and pregnant women participating in a PMTCT programwere characterized. HIV serotype was determined based on antibody reactivity to HIV type and group specific peptides derived from env gp120 V3 loop and gp41 immunodominant region using a multiplex immunoassay. Strain classification was determined by RT-PCR amplification and phylogenetic analysis of the env gp41 sequence; for rare subtypes, gag and pol sequences were also obtained and evaluated. Results: The peptide serotyping assay classified all infections as HIV-1 group M except for 2 HIV-2 infections. Phylogenetic analysis of 164 env sequences showed a high level of strain diversity. Subtype A predominated (43.9%) but 8 additional subtypes and 3 CRFs were found: subtype C (3.0%), D (9.8%), F1 (4.3%), G (12.2%), H (4.3%), J (1.2%), K (0.6%), L (0.6%), CRF01 (6.7%), CRF02 (8.5%), CRF11 (0.6%) plus unclassified (4.3%). Two subtype H, and the subtype J, K and L strains had concordant classification based on gag, pol , and env sequences. Conclusions: Molecular characterization of HIV-infected specimens collected in the DRC showmany different strains are circulating in the population and identified rare HIV subtypes H, J, K, and L for which very limited sequences are currently available. Subtype H, J and K sequences are most frequently found within CRFs thus the potentially pure subtype H, J, K and L strains identified here require confirmation by full genome sequencing. Continued surveillance of HIV strain diversity is important and essential to address the challenge posed by ongoing evolution of HIV and to monitor the rapidly changing HIV pandemic.

Poster Abstracts

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CROI 2015