Showing papers by "Nicole Vidal published in 2008"
TL;DR: This study illustrates the increasing HIV-1 diversity in France associating new (06FR-CRN) and old (CRF27_cpx and "MAL-like" 04FR-AUK) strains, which are rare in their region of origin but may have a possible founder effect in France.
Abstract: Background
Prevalence of HIV-1 non-B subtypes has increased overtime in patients diagnosed at the time of primary infection (PHI) in France. Our objective was to characterize in detail non-B strains which could not be genetically classified into the known subtypes/Circulating Recombinant Forms (CRFs).
31 citations
TL;DR: This is the first report providing molecular epidemiological evidence of heterosexual transmission of HIV-1 in China's general population and instrumental in identifying sources of the epidemic and in defining prevention strategies.
Abstract: Since the first outbreak of HIV-1 was reported in heroin users in China in 1989, HIV-1 has spread steadily among injection drug users, leading to an exponential growth of nationwide outbreaks from 1998 to 2004. However, the impact of sexual transmission on outbreaks of HIV in China's general population is still unclear. Through a governmental HIV/AIDS surveillance program, an HIV serological study was conducted in volunteers between 1996 and 2005 in Xishuangbanna Dai Autonomous Prefecture of Yunnan province. We performed the transmission reconstruction by molecular epidemiological tracing in a subset of the HIV-1-seropositive individuals diagnosed during this survey. Neighbor joining and maximum likelihood trees based on the HIV-1 pol and env genes were implemented to provide information on putative epidemiological links, which were then confirmed by contact tracing. Of 25,390 volunteers, 501 (2%) accumulated cases of HIV-1 infection (21.1% in needle-sharing drug users, 77.3% in heterosexual adults, 0.4% in homosexual adults, and 1.2% in children born from infected mothers) were diagnosed. Among 44 heterosexually infected and antiretroviral-naive local-traceable individuals (27 infected with HIV-1 subtype CRF01_AE, 15 with CRF08_BC, 1 with G, and 1 with a new B/C recombinant), 18 (40.9%) were coclustered into 8 transmission chains with an average size of 2.25 infections per chain. Phylogenetic and epidemiological linkages confirmed eight heterosexual transmission events. This is the first report providing molecular epidemiological evidence of heterosexual transmission of HIV-1 in China's general population. The reconstruction of transmission of current HIV-1 outbreaks by molecular epidemiological tracing is instrumental in identifying sources of the epidemic and in defining prevention strategies.
22 citations
TL;DR: Since the three viruses are clearly epidemiologically unlinked and share the same complex recombinant structure, they represent a circulating recombinant form, designated as CRF27-cpx, indicating that HIV-1 strains evolved over a long time.
Abstract: Full-length genomes were characterized for two samples, 02CD-LBR024 from the Democratic Republic of Congo (DRC) and 04FR-CD-KZS from France, that formed a separate subcluster with a previously characterized env subtype E isolate from DRC with a recombinant structure different from CRF01-AE. Since the three viruses are clearly epidemiologically unlinked and share the same complex recombinant structure, they represent a circulating recombinant form, designated as CRF27-cpx. The recombination pattern involves six different HIV-1 subtypes (A, E, G, H, J, and K) and a small unclassified fragment. The genetic distances are relatively high, indicating that CRF27-cpx evolved over a long time. Their prevalence is low (0.75%) and remained stable over time in the DRC. The existence of the 04FR.CD.KZS virus, in a patient who recently seroconverted in France, confirmed that these strains now circulate outside the DRC. Continuous monitoring of HIV-1 strains thus remains important to allow early identification of the introduction of new variants.
17 citations