Thermal disinfection of hotels, hospitals, and athletic venues hot water distribution systems contaminated by Legionella species.
Legionella spp. (> or = 500 cfu liter(-1)) were detected in 92 of 497 water distribution systems (WDS) examined. Thermal disinfection was applied at 33 WDS. After the first and second application of the disinfection procedure, 15 (45.4%) and 3 (9%) positive for remedial actions WDS were found, respectively. Legionella pneumophila was more resistant to thermal disinfection than Legionella non-pneumophila spp. (relative risk [RR]=5.4, 95% confidence intervals [CI]=1-35). WDS of hotels with oil heater were more easily disinfected than those with electrical or solar heater (RR=0.4 95% CI=0.2-0.8). Thermal disinfection seems not to be efficient enough to eliminate legionellae, unless repeatedly applied and in combination with extended heat flushing, and faucets chlorine disinfection.
Mouchtouri
Varvara
V
Department of Hygiene and Epidemiology, Faculty of Medicine, University of Thessaly, Larissa, Greece.
Velonakis
Emmanuel
E
Hadjichristodoulou
Christos
C
D004203:Disinfection / Q000379:methods*; D006361:Heating; D006761:Hospitals; D006801:Humans; D016952:Legionella pneumophila; D007877:Legionnaires' Disease / Q000517:prevention & control*; D008284:Maintenance and Engineering, Hospital / Q000379:methods; D012498:Sanitary Engineering / Q000379:methods*; D014871:Water Microbiology; D018508:Water Purification / Q000379:methods*