PREVENTION OF LEGIONELLA INFECTIONS IN A BONE-MARROW TRANSPLANT UNIT - MULTIFACETED APPROACH TO DECONTAMINATION OF A WATER-SYSTEM

OBJECTIVE: To evaluate measures intended to reduce Legionella infectio ns in patients undergoing bone marrow transplantation (BMT). DESIGN: O ngoing clinical and microbiological surveillance for Legionella coloni zation or infection was undertaken. All neutropenic patients with pulm onary infiltrates and fever unresponsive to broad-spectrum antibiotics were tested for Legionella organisms. SETTING: A 505-bed medical-surg ical hospital with a designated BMT unit. PATIENTS: Two hundred twenty -five patients underwent BMT, 201 were treated on a new BMT unit. The incidence of Legionella infections was compared to that seen in an est imated 150 neutropenic patients treated on other units. INTERVENTION. A combined approach to decontamination of a hospital water supply was assessed. This included heating, particulate filtration, ultraviolet s terilization, and monthly pulse hyperchlorination of water supplied to the BMT unit. The incidence of Legionella infections was assessed on the BMT unit and compared with the frequency elsewhere in the hospital . RESULTS: There were only three cases of Legionella pneumonia among 2 01 patients undergoing transplantation on a new BMT unit. In contrast, 33 cases of Legionella infections were detected from approximately 1 50 patients treated on general medical floors. CONCLUSION. A multiface ted approach to decontamination of a hospital water system led to a ma rked reduction in Legionella infections.