How many infections are caused by patient-to-patient transmission in intensive care units?
OBJECTIVE
The proportion of intensive care unit (ICU)-acquired infections that are a consequence of nosocomial cross-transmission between patients in tertiary ICUs is unknown. Such information would be useful for the implementation of appropriate infection control measures.


METHODS
A prospective cohort study during 18 months.


METHODS
Five ICUs from two university hospitals.


METHODS
All patients admitted for >/=48 hrs.


METHODS
ICU-acquired infections were ascertained during daily bedside patient and chart reviews. Episodes of potential cross-transmission were identified by highly discriminating genetic typing of all clinical and surveillance isolates of the ten bacterial species most frequently associated with nosocomial infections in ICUs. Isolation of indistinguishable isolates in two or more patients defined potential transmission episodes.


RESULTS
During 28,498 patient days, 431 ICU-acquired infections and 141 episodes of nosocomial transmissions were identified. A total of 278 infections were caused by the ten species that were genotyped, and 41 of these (14.5%) could be associated with transmissions between patients.


CONCLUSIONS
Infections acquired during treatment in modern tertiary ICUs are common, but a causative role of direct patient-to-patient transmission can only be ascertained for a minority of these infections on the basis of routine microbiological investigations.
Grundmann
Hajo
H
European Antimicrobial Resistance Surveillance System, National Institute for Public Health and the Environment, Bilthoven, The Netherlands.
Bärwolff
Sina
S
Tami
Adriana
A
Behnke
Michael
M
Schwab
Frank
F
Geffers
Christine
C
Halle
Elke
E
Göbel
Ulf B
UB
Schiller
Reinhold
R
Jonas
Daniel
D
Klare
Ingo
I
Weist
Klaus
K
Witte
Wolfgang
W
Beck-Beilecke
Kathrin
K
Schumacher
Martin
M
Rüden
Henning
H
Gastmeier
Petra
P
D001424:Bacterial Infections / Q000453:epidemiology / Q000382:microbiology / Q000635:transmission*; D003428:Cross Infection / Q000453:epidemiology / Q000382:microbiology / Q000635:transmission*; D006801:Humans; D015994:Incidence; D007362:Intensive Care Units / Q000706:statistics & numerical data*; D011446:Prospective Studies