Genital HIV-1 RNA predicts risk of heterosexual HIV-1 transmission

Department of Global Health, University of Washington, Seattle, WA 98195, USA.
Science translational medicine (Impact Factor: 15.84). 04/2011; 3(77):77ra29. DOI: 10.1126/scitranslmed.3001888
Source: PubMed


High plasma HIV-1 RNA concentrations are associated with an increased risk of HIV-1 transmission. Although plasma and genital HIV-1 RNA concentrations are correlated, no study has evaluated the relationship between genital HIV-1 RNA and the risk of heterosexual HIV-1 transmission. In a prospective study of 2521 African HIV-1 serodiscordant couples, we assessed genital HIV-1 RNA quantity and HIV-1 transmission risk. HIV-1 transmission linkage was established within the partnership by viral sequence analysis. We tested endocervical samples from 1805 women, including 46 who transmitted HIV-1 to their partner, and semen samples from 716 men, including 32 who transmitted HIV-1 to their partner. There was a correlation between genital and plasma HIV-1 RNA concentrations: For endocervical swabs, Spearman's rank correlation coefficient ρ was 0.56, and for semen, ρ was 0.55. Each 1.0 log(10) increase in genital HIV-1 RNA was associated with a 2.20-fold (for endocervical swabs: 95% confidence interval, 1.60 to 3.04) and a 1.79-fold (for semen: 95% confidence interval, 1.30 to 2.47) increased risk of HIV-1 transmission. Genital HIV-1 RNA independently predicted HIV-1 transmission risk after adjusting for plasma HIV-1 quantity (hazard ratio, 1.67 for endocervical swabs and 1.68 for semen). Seven female-to-male and four male-to-female HIV-1 transmissions (incidence <1% per year) occurred from persons with undetectable genital HIV-1 RNA, but in all 11 cases, plasma HIV-1 RNA was detected. Thus, higher genital HIV-1 RNA concentrations are associated with greater risk of heterosexual HIV-1 transmission, and this effect was independent of plasma HIV-1 concentrations. These data suggest that HIV-1 RNA in genital secretions could be used as a marker of HIV-1 sexual transmission risk.

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Available from: Deborah J Donnell, Oct 07, 2015
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    • "Most HIV transmission events globally occur via mucosal exposure to HIV found in male genital secretions (Baeten et al., 2011), but it remains unclear whether cell-free, cell-associated virus, or both are the primary source for sexually transmitted HIV (Anderson et al., 2010; Butler et al., 2010). It is also unclear if the transmission bottleneck selects for CCR5 tropic (R5) viruses (Schuitemaker et al., 2011), yet such viruses predominate in the blood early after infection (Rieder et al., 2011; Zhu et al., 1993). "
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    ABSTRACT: We present a case of sexual transmission of HIV-1 predicted to have CXCR4-tropism during male-to-male sexual exposure. Phylogenetic analyses exclude cell-free virus in the seminal plasma of the source partner and possibly point to the seminal cells as the origin of the transmission event.
    Virology 10/2012; 434(1). DOI:10.1016/j.virol.2012.09.010 · 3.32 Impact Factor
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    • "Secondary analysis of concurrent trends in annual reported cases of syphilis and gonorrhea, but no formal assessment Provision of free ART was associated with a 53% reduction in the estimated HIV transmission rate Post-HAART transmission rate estimated as 0.184 new infections per prevalent case Katz et al. [40] (2002) Inferences drawn from observation of concurrent changes in HIV incidence rates, reported sexual behavior, STI diagnoses, and ART use among population in clinical care — Secondary analysis of concurrent trends in reported risk behaviors and cases of rectal gonorrhea among MSM, but no formal assessment ART impact on HIV transmission has been counterbalanced by increased reported risk behaviors Law et al. [37] (2011) "
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    • "These results have profound implications for important virus-related processes in which the VL is a key determinant, such as the progression, and especially in the transmission of the infection. This is given that infectiousness can be directly correlated with the concentration of HIV-RNA in plasma, which associates with shedding of the virus into genital track secretions [21,22]. The evidence suggests a strong correlation between the VL and HIV transmission rates [23-25]. "
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