Dataset Information

Rates of blood cultures positive for vancomycin-resistant Enterococcus in Ontario: a quasi-experimental study

ABSTRACT:

Background:

Some Ontario hospitals have discontinued active screening and isolation programs for vancomycin-resistant Enterococcus (VRE). The aim of this study was to determine whether this practice change is associated with a change in the rate of rise of VRE-positive blood cultures.

Methods:

All Ontario hospitals are mandated to report VRE bacteremia. Using this publicly reported data set, we included all validated results between January 2009 and June 2015. Beginning in June 2012, some hospitals discontinued active VRE screening and isolation programs (intervention). We used an interrupted time series Poisson regression to assess the slope change in the incidence rate of VRE-positive blood cultures (primary outcome) after versus before the intervention. Hospitals that continued to screen were the comparison group. Incidence rates were adjusted for hospital type and clustering within hospital site; slope changes are presented as incidence rate ratios (IRRs) with 95% confidence intervals (CIs).

Results:

In hospitals that had ceased screening (n = 13), there was an increase in slope after screening and isolation were discontinued compared with before screening and isolation were discontinued (slope change IRR 1.25 [95% CI 1.01-1.54]). In hospitals that continued screening (n = 50), the slope was not significantly different after June 2012 compared with before June 2012 (slope change IRR 0.81 [95% CI 0.56-1.15]).

Interpretation:

There was a significant increase in the rate of rise of VRE-positive blood cultures in hospitals that discontinued active VRE screening and isolation programs but not in hospitals that continued to screen and isolate. Hospitals aiming to minimize rising rates should consider maintaining active screening and isolation programs.

SUBMITTER: Johnstone J

PROVIDER: S-EPMC5509029 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature

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