Impact of an Intensive Terminal Cleaning and Disinfection (C/D) Program Involving Selected Hospital Rooms on Endemic Nosocomial Infection (NI) Rates of Common Pathogens at a Tertiary Care Medical Center

Background: Standard terminal C/D of rooms newly vacated by patients infected and/or colonized with MDRABC, Cd, VRE, and MRSA may be inadequate in eliminating these common pathogens from room surfaces. 

Objective: To evaluate the impact of an intensive terminal C/D program involving 1 round of C/D with 10% bleach followed by hydrogen peroxide vapor (1xC/D+HPV) treatment on the endemic nosocomial infection rates of multi-drug resistant Acinetobacter baumanni (MDRABC), Clostridium difficile  (Cd), vancomycin-resistant Enterococcus (VRE), and methicillin-resistant Staphylococcus aureus  (MRSA ).

Methods: The setting was a 900-bed community tertiary care medical center. A new C/D protocol of freshly-vacated hospital rooms was implemented on Dec 15, 2008, as follows. 1.  1xC/D+HPV treatment of rooms vacated by MDRABC+ patients  with follow up environmental cultures (vs 4 rounds of C/D [4xC/D] with follow-up environmental cultures previously) ;  2. Use of a priority scale for 1xC/D+HPV treatment of other rooms based on ward location (e.g . intensive care vs other units) and certain attributes of the most recent room occupant (e.g. Cd, VRE, or MRSA status,  length of stay in the room, and body site of infection and/or colonization [e.g. wound or stool]); and 3. 4xC/D of rooms vacated by patients with Cd infection during the same hospitalization when 1xC/D+HPV was not possible.   NI rates (per 1000 patient [pt] days) during pre- and post-intervention periods (excluding pediatric units) were compared.  Pre-intervention period spanned from Jan 07-Jul 08 (293,001 pt days) for Cd and VRE, and from Jan 07-Nov 08 for MDRABC (362,101 pt days) and  MRSA (365,926 pt days) NIs.  Post-intervention period spanned from Jan-Dec 09, 193,907 pt days for MDRABC and 196,313 pt days for MRSA, Cd, and VRE NIs. Variation in pt days was due to implementation of 4xC/D of Cd rooms without HPV in Aug 08, and exclusion of burn unit rooms from calculation of MDRABC NI rates (considered “non-endemic” in this unit).   

Results: A total of 1,123 rooms underwent 1xC/D+HPV in 2009 (average 4 rooms/weekday). There was a significant or near significant decrease in NI rates of Cd (0.95 vs 0.56 cases/1000 pt days, rate ratio [RR] 0.6, P<0.0001), VRE (0.31 vs 0.15 cases/1000 pt days, RR 0.5, P<0.001), and MRSA (0.44 vs 0.3 cases/1000 pt days, RR 0.76, P=0.059).  MDRABC NI rate also dropped in the post-intervention period (0.03 vs 0.015 cases/1000 pt days), but the difference did not reach statistical significance (RR 0.47, P=0.23).  

Conclusions: Implementation of an intensive terminal C/D protocol involving 1xC/D+HPV treatment of selected newly-vacated hospital rooms as described was associated with significant decreases in the rates of Cd and VRE NIs, near-significant decrease in the rate of MRSA NIs, and was effective in maintaining an already low MDRABC NI rate in an endemic setting.