Nosocomial Serratia marcescens infections associated with extrinsic contamination of a liquid nonmedicated soap.
OBJECTIVE
To determine the role of nonmedicated soap as a source of Serratia marcescens nosocomial infections (NIs) in hospital units with endemic S marcescens NI and to examine the mechanisms of soap colonization.


METHODS
University-affiliated tertiary-care hospitals.


METHODS
A prospective case-control study and an environmental investigation were performed to assess the relationship between S marcescens NIs in hospital units and S marcescens-contaminated soap. Soap-bottle use and handwashing practices were reviewed. Cultures of healthcare workers' (HCWs) hands were obtained before and after hand washing with soap.


RESULTS
5 of 7 hospital units with S marcescens NIs had soap bottles contaminated with S marcescens, compared to 1 of 14 other units (P=.006). After hand washing with an S marcescens-contaminated soap pump, HCWs' hands were 54 times more likely to be contaminated with S marcescens (P<.001).


CONCLUSIONS
Extrinsic contamination of a non-medicated liquid soap by S marcescens resulted in handborne transmission of S marcescens NIs by HCWs in our setting. This finding led to the application of strict guidelines for nonmedicated soap use and to the reinforcement of alcoholic hand disinfection.
Sartor
C
C
Comité de Lutte contre les Infections Nosocomiales, Hôpital de la Conception, Marseille, France.
Jacomo
V
V
Duvivier
C
C
Tissot-Dupont
H
H
Sambuc
R
R
Drancourt
M
M
D016022:Case-Control Studies; D003428:Cross Infection / Q000453:epidemiology* / Q000382:microbiology; D004196:Disease Outbreaks; D005602:France; D006235:Hand Disinfection; D006801:Humans; D009096:Multi-Institutional Systems; D011446:Prospective Studies; D016868:Serratia Infections / Q000453:epidemiology* / Q000382:microbiology; D012706:Serratia marcescens / Q000302:isolation & purification*; D012915:Soaps
D012915:Soaps