A survey of methods used to detect nosocomial legionellosis among participants in the National Nosocomial Infections Surveillance System.
OBJECTIVE
To help define the scope of nosocomial legionnaire's disease (LD) and to assess use of recommended diagnostic methods and transmission control practices.


METHODS
We surveyed 253 hospitals participating in the National Nosocomial Infections Surveillance (NNIS) System. The anonymous survey included questions about episodes of nosocomial LD, environmental sampling practices, maintenance of hospital water systems, and diagnostic techniques.


RESULTS
Of 192 hospitals that responded, 29% reported at least one episode of nosocomial LD from 1990 through 1996, and 61% of these reported at least two episodes. Of 79 hospitals with transplant programs, 42% reported nosocomial LD, compared with 20% of hospitals without transplant programs. Environmental sampling had been conducted by 55% of hospitals, including 79% of those reporting nosocomial LD. Legionella were isolated in 34% that sampled potable water and 19% that sampled cooling system reservoirs. Supplemental potable-water decontamination systems were installed in 20% of hospitals. Only 19% routinely performed testing for legionellosis among patients at high risk for nosocomial LD.


CONCLUSIONS
Nosocomial LD is relatively common among NNIS hospitals, especially those performing organ transplants. Environmental sampling for Legionella is a common practice among NNIS hospitals, and Legionella often are isolated from sampled hospital cooling towers and hospital potable-water systems. Hospitals have responded to suspected nosocomial LD infection with a variety of water sampling and control strategies; some have not attempted to sample or decontaminate water systems despite identified transmission.
Division of Bacterial and Mycotic Diseases, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Public Health Service, US Department of Health and Human Services, Atlanta, Georgia 30333, USA.
A E
AE
Fiore
J C
JC
Butler
T G
TG
Emori
R P
RP
Gaynes
D000328:Adult; D001431:Bacteriological Techniques; D002675:Child, Preschool; D003428:Cross Infection / Q000175:diagnosis* / Q000453:epidemiology; D003666:Decontamination / Q000379:methods; D019937:Diagnostic Techniques and Procedures; D006306:Health Surveys; D006801:Humans; D007875:Legionella / Q000302:isolation & purification; D007876:Legionellosis / Q000175:diagnosis* / Q000453:epidemiology; D011795:Surveys and Questionnaires; D014481:United States / Q000453:epidemiology; D014871:Water Microbiology