Efficacy of high-efficiency particulate air filtration in preventing aspergillosis in immunocompromised patients with hematologic malignancies.

Objectives: To describe and investigate the cause of an outbreak of 10 cases of nosocomial invasive infection with Aspergillus flavus in a hematologic oncology patient care unit.

Design: A retrospective cohort study.

Setting: The hematologic oncology unit of a comprehensive cancer center.