北京男男性行为人群HIV-1序列和流行趋势分析

摘要

Objective To analyze genetic characteristics of HIV isolated from men who have sex with men(MSM) in Beijing and predict the epidemic trend in this population.Methods All of the HIV gene sequences in our laboratory obtained from MSM in Beijing were used,which were aligned with all of the HIV gene sequences from MSM and other populations in China downloaded from Los Alamos HIV Database.Phylogenetic trees were constructed by using software PhyML 3.0,based on which the relationships of prevalent HIV strains between Beijing MSM and other populations in China were further explored.The evolution rate,the time of most recent common ancestor (tMRCA),the epidemic parameters,the reproductive number (R0) were calculated by using software BEAST to predict HIV evolution and epidemic characteristics.Results Multiple HIV subtypes,including subtype B,CRF01_AE and CRF07_BC,were found to be prevalent among MSM in Beijing.In ML tree constructed based on strains from the whole country,three clusters including B-1,CRF01_AE-1,and CRF01_AE-2 were found among the MSM in Beijing (accounting for 40％).At least three independent introduction of B 1 cluster strains into Beijing MSM were found,which were at March 1991 (July 1984-February 1997),January 1994 (January 1989-January 1998),April 1991 (August 1984-January 1996).For CRF01_AE strains,two clusters including CRF01_AE-1 and CRF01_AE-2 were introduced into the population at December 2000 (March 1998-January 2003) and December 2001 (January 2000-July 2003) respectively.The population epidemiology of HIV in Beijing MSM was reconstructed based on sequences.The CRF01_AE-1 cluster spread more quickly than the other two clusters,and the evolution rate was higher.Conclusion Multiple HIV subtypes were found prevalent among MSM in Beijing.Although subtype B strain was introduced into Beijing MSM earlier than CRF01_AE strain,CRF01_AE strain increased more quickly than subtype B strain.More research and control of the CRF01_AE prevalence will be helpful for prevention and control of HIV epidemic in MSM in Beijing.%目的 分析北京MSM人群HIV序列特征,预测北京该人群中HIV流行趋势.方法 汇总本实验室获得的北京MSM人群HIV序列,下载Los Alamos HIV Database中我国MSM人群及其他人群中流行的HIV序列,利用PhyML3.0、BEAST等软件重建北京MSM人群系统发育树、估算突变速率、推断tMRCA、重建群体流行动态参数、计算再生指数R0值,分析北京MSM人群与其他人群HIV流行的相关关系,推断进化和流行特征.结果 北京MSM人群中流行的HIV-1亚型包括B、CRF0 1_AE和CRF07 BC.在全国HIV毒株ML进化树中,北京MSM簇(北京MSM人群所占比例≥40％)共有3簇,即B-1簇、CRF01 AE-1簇、CRF01 AE-2簇.B1簇毒株是由至少3次传入事件进入北京MSM人群的,传入时间分别为1991年3月(1984年7月至1997年2月)、1994年1月(1989年1月至1998年1月)、1991年4月(1984年8月至1996年8月).CRF01_AE毒株由2次传入事件进入北京MSM人群,传人时间分别为2000年12月(1998年3月至2003年1月)和2001年12月(2000年1月至2003年7月).流行特征重塑分析显示,CRF01 AE-1簇近年来增长速度较快、突变速率较高.结论 北京MSM人群中存在多种HIV亚型毒株流行,其中B亚型毒株传入时间最早,但增长趋势趋于平稳;CRF01 AE毒株传入时间较晚、但增长迅速,对HIV在北京地区的流行具有明显的推动作用,因此对CRF01 AE毒株的防控有助于减少该地区HIV的流行.