医院内感染(院内感染)是指住院患者入院时既不存在,亦不存在其潜伏期的感染,已成为现在感染性疾病的重要课题。据调查1986年以来,美国每年4000万住院病例中约5%~10%患者获得院内感染[1],每年用于治疗院内感染的费用高达5~7亿美元。最近几十年来,美国和西欧各国对院内感染进行了 Hospital infection (nosocomial infection) refers to the hospitalized patients neither exist at admission nor their latent infection, has now become an important issue of infectious diseases. According to the survey, about 5% to 10% of the 40 million hospitalized cases in the United States have been infected with nosocomial infections since 1986 [1], and the annual cost for treating nosocomial infections is as high as 500 million to 700 million U.S. dollars. In recent decades, the United States and Western European countries have carried out nosocomial infections