1992--2008年深圳HIV-1CRF01_AE重组株的流行趋势与进化规律

Epidemic trend and evolution of HIV-1 CRF01 _AE strains isolated from 1992 through 2008 in Shenzhen district

目的了解HIV-1CRF01_AE重组株在深圳地区的流行情况，并分析其流行趋势及进化规律。方法收集深圳地区1992--2008年HIV确认阳性血液样本489份，应用巢式聚合酶链反应（Nested-PCR）技术，对样本膜蛋白（Env）基因进行扩增，并对其基因区核苷酸序列进行测定，判定亚型结果。对获得的CRF01_AE重组株核酸序列进行系统进化分析，并计算基因离散率。结果共有465份样本获得分型结果，其中CRF01_AE重组株样本300份（占64．5％）。1992-1999、2000—2005和2006--2008年3个时间段CRF01_AE重组株所占比例分别为56．8％（21／37）、68．4％（78／114）和64．0％（201／314）；在这3个时间段内，经异性性传播的比例分别为52．4％（11／21）、43．6％（34／78）和45．8％（92／201），经同性性传播的比率上升明显，分别为4．8％（1／21）、0．0％（0／78）和22．4％（45／201），经吸毒传播的比例分别为19．0％（4／21）、51．3％（40／78）和30．8％（62／210）。系统进化分析发现，不同时间段的样本出现明显的时间聚集现象，并伴有传播途径的聚集及交叉感染现象。各时间段CRF01_AE重组株组内基因离散率分别为（8．783±4．717）％、（11．054±7．141）％、（13．218±4．080）％，有明显的增大趋势。结论HIV-1CRF01_AE重组株是深圳地区的主要流行株，主要经异性性行为、同性恋和吸毒人群传播，随着时间的推移毒株变异程度逐渐增大。

Objective To study the prevalent status of CRF01_AE strains of recombinant HIV-1 in Shenzhen and their source of infection in order to predict the epidemic trend and evolution. Methods A total of 489 samples of HIV-1 positive plasma were collected from 1992 to 2008 in Shenzhen. HIV-1 Env genes were amplified by nested-PCR from RNA. Subtype analysis were performed on the nucleotide sequence data. CRF01 _AE sequences were analyzed by phylogenetic methods and characterized by calculating the genetic distance. Results A total of 300 CRF01_AE strain sequences were amplified, accounting for 64. 5 % of all genotyped samples of all the 465 samples. The CRF01 _AE strains of recombinant in 1992 - 1999, 2000 -2005 and 2006 -2008 accounted for 56. 8% （21/37） ,68.4% （78/114） and 64. 0% （201/314） of genotyped samples, respectively. And in these three periods of times,52.4% （11/21 ） ,43.6% （34/78） and 45.8% （92/201） were heterosexually acquired adults; 4. 8% （ 1/21 ） ,0. 0% （0/78） and 22. 4% （45/201） were homosexually acquired adults; 19.0% （4/21） ,51.3% （40/78） ,30. 8% （62/210） were intravenous drug users, respectively. Phylogenetic tree analysis revealed that HIV samples from different period of time showed distinct aggregation in time and transmission as well as cross infection. The gene divergence rate of CRF01_AE strains in the three different periods of time were（8. 783 ±4. 717） % , （ 11. 054 ±7. 141 ） % ,and （13. 218 ± 4. 080）%, respectively. Conclusion CRF01_AE is the major epidemic strains in Shenzhen, which is transmitted through heterosexual contact, MSM and intravenous drug users. The gene variation increased gradually as time goes by.