The Role of Environmental and Electronic Surveillance in the Control of Invasive Aspergillosis among Ambulatory Hematologic Transplant Patients

ISSUE: Invasive Aspergillosis (IA) is a frequent and morbid complication of hematologic transplantation. Construction in health care facilities has been associated with outbreaks of IA among immunocompromised patients, and effective infection control programs in hospitals have been shown to decrease nosocomial IA. Little is known about acquisition of IA in the outpatient setting where an increasing fraction of health care associated with transplantation is occurring. PROJECT: We developed a novel electronic surveillance system for the detection of communicable diseases among ambulatory hematologic transplant patients. During the course of an extensive addition to the ambulatory cancer care clinic, we initiated outdoor and indoor environmental sampling for Aspergillus. Results from air sampling were correlated with microbiologically confirmed cases of Aspergillus from the electronic surveillance database. RESULTS: Microbiologic evidence of Aspergillosis was identified in 42 ambulatory transplant patients in 2005. Concentrations of Aspergillus within the ambulatory clinic remained uniformly low both prior to and throughout construction. The burden of Aspergillus isolated outside varied widely, and followed a previously described seasonal pattern. Cases of IA were closely correlated with the outdoor Aspergillus concentrations. image LESSONS LEARNED: Electronic surveillance for communicable disease among high-risk ambulatory patients may yield important information about trends in infections. The risk of IA among ambulatory hematologic transplant patients is strongly correlated with ambient concentrations of Aspergillus. The role of infection control and antifungal prophylaxis in protecting ambulatory at-risk patients needs to be reevaluated.