慢性阻塞性肺疾病（COPD）严重威胁人类健康，呼吸道细菌感染是COPD患者急性加重的重要诱因，传统的研究手段难以全面揭示呼吸道细菌多样性，近年来采用宏基因组学技术探索COPD呼吸道细菌种群构成及变化的研究，但文献报道不多，且存在以下问题：①缺乏针对同一COPD人群不同病程中细菌种群变化的纵向研究；②在COPD急性加重期呼吸道细菌种群构成是否变化方面不同研究结果存在矛盾；③民族、气候分布能够影响呼吸道细菌种群变化，但是否能够影响COPD呼吸道细菌构成尚不清楚。因此，本课题采用Miseq高通量测序方法，分析云南不同地区不同民族COPD人群在不同病程中呼吸道细菌微生态变化，探索地域和民族特异的呼吸道微生态状态以及与COPD急性加重相关的特异菌种，阐明呼吸道细菌种群结构变化对疾病病程的影响，对指导我们采取有针对性防控和治疗措施，减少患者急性加重住院次数，缩短患者病程，提供重要的理论基础。

Chronic obstructive pulmonary disease (COPD) is a common disease of respiratory system threatening the health of people, and respiratory tract infection is one of the important reasons due to acute exacerbation in COPD patients. However, the traditional research methods can’t fully reveal the bacterial diversity of the respiratory tract. At present, there are a few literatures on the composition and changes of respiratory tract bacterial populations with the technology of metagenomics which are related to the occurrence and development of COPD. In addition some questions consistently exist as following: ①It is few longitudinal study of the change of bacterial populations in the different course of COPD.②whether the constitution of respiratory bacterial population changes or not, there are contradictions between different research results.③It’s clear that the bacterial diversity of other respiratory diseases is related with the climate and race, whereas it keep vague whether it can affect the composition of respiratory bacteria in COPD. Therefore, to analyze the changes of microbiome in respiratory tract of patients with different course of COPD between different regions and ethnic groups in Yunnan province, investigate the microenvironment of respiratory and the markers related with the exacerbation of COPD, and clarify the effect of respiratory tract bacterial population structure on the course of COPD. That will establish a important theoretical basis in our study, for the guidance of taking targeted prevention and treatment,reduce the number of patients with acute exacerbation of hospitalization, shorten the course of the disease.