The association between infection control interventions and carbapenem-resistant Enterobacteriaceae incidence in an endemic hospital

Abstract Background Israel experienced a national outbreak of carbapenem-resistant Enterobacteriaceaee (CRE) starting in 2006. Aim To assess the association between infection control (IC) interventions implemented in a referral hospital in Israel and (CRE) incidence. Methods Retrospective quasi-experimental study of prospectively collected data. CRE incidence, defined as the number of patients newly acquiring CRE in surveillance or clinical samples per 100,000 hospitals days (HD), was plotted quarterly between 2005 to 2016. IC interventions were applied at different time-points throughout this period. We collected data on IC staffing, number of rectal surveillance cultures and carbapenem consumption. We used auto-correlated segmented linear regression analysis to assess the time-points where a significant change in the CRE incidence trend occurred and assessed the relationship between the timing of IC intervention implementation and observed CRE trends. Trends between time-points are expressed as quarterly percent change (QPC) with 95% confidence intervals. Findings Between 2005-2008, CRE incidence increased significantly, QPC 19.7% (11.5-28.4%), reaching a peak of 186.6 new acquisitions/100,000 HD. From mid-2011 until the end of follow-up, there was a significant decreasing incidence trend, QPC -4.5 (-6.4 to -2.5). Cohorting of patients, screening of contacts and high-risk patients on admission were insufficient to control the epidemic. Improved hand hygiene compliance, cohorting with dedicated nursing staff, addition of regular screening in high-risk departments and carbapenem restriction were required. Decreasing CRE incidence was observed with an ID/IC staffing of 1.2-1.5/100 beds and 20,000-36,000 yearly CRE surveillance samples. Conclusions A multifaceted hospital-wide intervention program is required to control CRE in hospital settings.