本研究以当前我国MSM（男男同性性行为）人群HIV流行的显著特点为切入点，引出一个我们一直忽略了的重要科学问题。本项目以北京地区MSM人群的HIV早期感染者为研究对象，针对HIV的双重感染问题开展研究。将最近发展的单基因组扩增（SGA）、直接测序技术引入到我们建立的HIV双重感染的检测方法中。研究目标：1）揭示我国北京地区MSM人群的HIV双重感染率；2）阐述我国北京地区MSM人群的HIV双重感染的相关风险因素；3）了解我国北京地区MSM人群的HIV双重感染对患者疾病进程的影响。这些结果会对HIV传播的机制、MSM人群的干预和防治研究提供科学依据。

The entry path of this project is the distinctive features of the HIV prevalence among MSM (man who have sex with man) population in China. And this make me realize an important scientific problem which is always ignored in our country. We plan to select HIV early infectors in MSM population of Beijing district as the study objects and research for dual infection in this population. Of interest, the recently developed single genome amplification (SGA) followed by direct sequencing technology will be introduced into the method for detecting HIV dual infection. The objective of this project are as follow: 1) to reveal the incidence of dual infection in MSM population of Beijing district, 2) to elucidate the risk factors related with HIV dual infection, 3) to understand the impact of dual infection on the patients' disease progression. These results will provide the scientific basis for elucidating the transmission of human immunode?ciency virus type 1 (HIV-1) and for intervention and prevention research in MSM population.