Hawes Stephen E, Sow Papa Salif, Stern Joshua E, Critchlow Cathy W, Gottlieb Geoffrey S, Kiviat Nancy B
Department of Epidemiology, School of Public Health and Community Medicine, University of Washington, Seattle, Washington 98103, USA.
AIDS. 2008 Nov 30;22(18):2517-25. doi: 10.1097/QAD.0b013e328315cdbc.
The differing magnitude of the HIV-1 and HIV-2 epidemics is likely a consequence of differing transmission rates between the two viruses. Similar to other sexually transmitted pathogens, risk of HIV-1 and HIV-2 transmission is likely associated with the presence and amount of HIV in the genital tract. Thus, understanding patterns of, and risk factors for HIV genital tract shedding is critical to effective control of HIV transmission.
We evaluated HIV DNA and RNA detection in cervicovaginal specimens among 168 HIV-1 and 50 HIV-2-infected women in Senegal, West Africa. In a subset of 31 women (20 with HIV-1, 11 with HIV-2), we conducted a prospective study in which cervicovaginal specimens were taken at 3-day intervals over a 6-week period.
We found significantly lower rates and levels of HIV-2 RNA (58% shedding; 13% with >1000 copies/ml) in the female genital tract than HIV-1 RNA (78% shedding; 40% with >1000 copies/ml) (P = 0.005 and 0.005, respectively), and shedding correlated with plasma viral load irrespective of virus type (odds ratio = 1.9, 95% confidence interval = 1.3-2.8 for each log10 increase in HIV viral RNA). Plasma viral load, not HIV type, was the strongest predictor of genital viral load. Over 80% of closely monitored women, regardless of HIV type, had at least intermittent HIV RNA detection during every 3-day sampling over a 6-week time period.
These data help in explaining the different transmission rates between HIV-1 and HIV-2 and may provide new insights regarding prevention.
HIV-1和HIV-2流行程度的差异可能是这两种病毒传播率不同的结果。与其他性传播病原体类似，HIV-1和HIV-2的传播风险可能与生殖道中HIV的存在情况和数量有关。因此，了解HIV生殖道脱落的模式和危险因素对于有效控制HIV传播至关重要。
我们评估了西非塞内加尔168名感染HIV-1和50名感染HIV-2的女性宫颈阴道标本中的HIV DNA和RNA检测情况。在31名女性（20名感染HIV-1，11名感染HIV-2）的子集中，我们进行了一项前瞻性研究，在6周的时间内每隔3天采集宫颈阴道标本。
我们发现，女性生殖道中HIV-2 RNA的检出率和水平（58%有脱落；13%的病毒载量>1000拷贝/毫升）显著低于HIV-1 RNA（78%有脱落；40%的病毒载量>1000拷贝/毫升）（P值分别为0.005和0.005），且无论病毒类型如何，脱落情况均与血浆病毒载量相关（HIV病毒RNA每增加1个log10，优势比=1.9，95%置信区间=1.3 - 2.8）。血浆病毒载量而非HIV类型是生殖道病毒载量的最强预测指标。超过80%密切监测的女性，无论感染何种HIV类型，在6周时间内每3天采样时至少有间歇性的HIV RNA检测结果。
这些数据有助于解释HIV-1和HIV-2之间不同的传播率，并可能为预防提供新的见解。
