This study will investigate the hypothesis that enhanced terminal room disinfection protocols (using chlorine-based cleaning agents with or without UV-C light-emitting devices) will decrease the overall risk of HAIs in the hospital and, more specifically, in subsequent patients who are cared for in the same room. This prospective investigation will employ a crossover design utilizing four room cleaning/disinfection protocols in 9 hospitals, including 2 tertiary care, 1 VA, and 6 community hospitals. Phase T2 data from this study will be useful in assessing the clinical efficacy and feasibility of individual disinfection strategies. Thus, the goals of the investigators proposed research are to 1) determine the efficacy and feasibility of enhanced terminal room disinfection strategies to prevent HAIs and 2) determine the impact of environmental contamination on acquisition of MDR-pathogens among hospitalized patients.