在全部院内感染病例中,院内肺炎(hospitalacquired pneumonia,HAP)的患病率约占15％～18％,病情多较严重,病死率高达20％～50％,而且大约15％住院死亡的病例伴有HAP。尽管HAP的诊断技术近年来已取得了重大进展,但在许多情况下准确区分菌落寄生或感染仍然比较困难,根据HAP的流行病学合理地选用抗生素治疗具有重要意义。本文就其研究进展作一简要介绍。 Of the total number of nosocomial infections, the prevalence of HAP is about 15% to 18% and the condition is more serious with a case fatality rate of 20% to 50% and about 15% of hospitalized cases of death HAP. Although significant advances have been made in the diagnostic techniques of HAP in recent years, accurate classification of colony parasites or infections is still difficult in many cases and rational use of antibiotic therapy based on the epidemiology of HAP is of great importance. This article gives a brief introduction of its research progress.