Epidemiology of nosocomial fungal infections: Invasive aspergillosis and the environment

The incidence rates of invasive aspergillosis have increased dramatically d uring the last two decades, and, despite all diagnostic and therapeutic eff orts, outcome is often fatal. Therefore, preventive measures are of major i mportance in the control of invasive aspergillosis, and require full unders tanding of the epidemiology of this devastating disease. The environment ha s been suggested to play a crucial role in the epidemiology of invasive asp ergillosis. Aspergillus spores are released in the air and may remain airbo rne for prolonged periods. As a result, spores are ubiquitously found in ai r and contaminate anything in contact with air. It has been hypothesized th at the inhalation of airborne Aspergillus spores, either directly or throug h intermediate nasopharyngeal colonization, is a direct cause of pulmonary infection in immunocompromised patients. Recently, water has been suggested as an additional source of "airborne" Aspergillus spp. This review summari zes the current knowledge on the role of the environment in the epidemiolog y of invasive aspergillosis. (C) 1999 Elsevier Science Inc.