Invasive aspergillus infection: possible non-ward common source within the hospital environment.

Six immunocompromised patients housed in widely separated portions of a hospital campus developed invasive aspergillosis during a single month. This represented a significant increase (P less than .001) in the number of cases observed over the 3 years which included this event (19 cases in 36 months). Epidemiological investigation suggested that this cluster of cases was due to a common source outbreak related to construction activity in a central radiology suite serving the hospital. Such non-ward exposures to nosocomial hazards are becoming increasingly important for immunosuppressed hosts.