Impact of Isolating Clostridium difficile Carriers on the Burden of Isolation Precautions: A Time Series Analysis.

Background: The isolation of asymptomatic Clostridium difficile (CD) carriers may decrease the incidence of hospital-associated C. difficile infections (CDI), but its impact on isolation precaution needs is unknown. Methods: Time series analysis to investigate the impact of isolating CD carriers on the burden of isolation precautions from 2008 to 2016 in a Canadian hospital. To account for the changes in C. difficile infection control policies, the series was divided into three intervention periods. Period 1 (2008-2011): isolation of patients with CDI until symptom resolution; Period 2 (2011-2013): isolation of patients with CDI until discharge; and Period 3 (2013-2016): isolation of patients with CDI and CD carriers until discharge. We compared the prevalence of isolation-days for C. difficile (i.e. for either CDI or carriage) per 1,000 patient-days between study periods. Changes in trend were analyzed by segmented regression analysis. Results: 806,357 patient-days and 20,455 isolation-days were included. Isolation-day prevalence during Periods 1, 2 and 3 were 12.9, 26.2 and 37.8 isolation-days per 1,000 patient-days, respectively (p