Environmental Control to Reduce Transmission ofClostridium difficile

Restrictive antibiotic policies and infection control measures have been shown to reduce the incidence of Clostridium difficile-associated diarrhea (CDAD) among hospitalized patients. To date, the role of environmental disinfectants in reducing nosocomial CDAD rates has not been well studied. In a before-and-after intervention study, patients in 3 units were evaluated to determine if unbuffered 1:10 hypochlorite solution is effective as an environmental disinfectant in reducing the incidence of CDAD. Among 4252 patients, the incidence rate of CDAD for bone marrow transplant patients decreased significantly, from 8.6 to 3.3 cases per 1000 patient-days (hazard ratio, 0.37; 95% confidence interval, 0.19-0.74), after the environmental disinfectant was switched from quaternary ammonium to 1:10 hypochlorite solution in the rooms of patients with CDAD. Reverting later to quaternary ammonium solution increased the CDAD rate to 8.1 cases per 1000 patient-days. No reduction in CDAD rates was seen among neurosurgical intensive care unit and general medicine patients, for whom baseline rates were 3.0 and 1.3 cases per 1000 patient-days, respectively. Unbuffered 1:10 hypochlorite solution is effective in decreasing patients' risk of developing CDAD in areas where CDAD is highly endemic. Presumed mechanisms include reducing the environmental burden and the potential for C. difficile transmission among susceptible patients.