Abbreviated duration of superheat-and-flush and disinfection of taps for Legionella disinfection: lessons learned from failure.
One medical center in southern Taiwan faced an outbreak of nosocomial Legionnaires' disease; a total of 81 suspected cases were detected during an 8-month period. Baseline environmental surveillance showed that 80% of the distal sites in intensive care units (ICUs) were positive for Legionella pneumophila. Superheat-and-flush was selected for hospital water supply disinfection because it required no special equipment, and it can be initiated expeditiously. We conducted 2 episodes of superheat-and-flush based on the published recommendations from the Department of Health, Taiwan; US Centers for Disease Control and Prevention; and American Society of Heating, Refrigerating, and Air-Conditioning Engineers. Both flushes failed to control colonization of Legionella in the hospital water supply. The rate of distal sites positive for Legionella in wards and ICUs was 14% and 66%, respectively, 10 days after the second flush. The effect of replacement of faucets and showerheads in ICUs appeared to be insignificant in colonization of Legionella. The application of superheat-and-flush for flush duration of 5 minutes was ineffective. Superheat-and-flush may not be economic for a large medical center because it could be costly and labor intensive.
Chen
Yao-shen
YS
Section of Infectious Diseases of the Department of Internal Medicine, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan, Republic of China.
Liu
Yung-ching
YC
Lee
Susan Shin-jung
SS
Tsai
Hung-chin
HC
Wann
Shue-ren
SR
Kao
Chih-hsiang
CH
Chang
Chiao-Lin
CL
Huang
Wen-kuei
WK
Huang
Tsi-shu
TS
Chao
Hsueh-lan
HL
Li
Ching-hsien
CH
Ke
Chin-mei
CM
Lin
Yu-sen Eason
YS
D000046:Academic Medical Centers; D003428:Cross Infection / Q000453:epidemiology / Q000517:prevention & control* / Q000635:transmission; D004196:Disease Outbreaks / Q000517:prevention & control*; D004203:Disinfection / Q000379:methods*; D006361:Heating; D006801:Humans; D017053:Infection Control / Q000379:methods; D016952:Legionella pneumophila / Q000302:isolation & purification; D007877:Legionnaires' Disease / Q000453:epidemiology / Q000382:microbiology / Q000517:prevention & control* / Q000635:transmission; D008284:Maintenance and Engineering, Hospital / Q000379:methods*; D013624:Taiwan / Q000453:epidemiology; D014871:Water Microbiology; D014881:Water Supply