Preventing the Transmission of Multidrug-Resistant Organisms: Modeling the Relative Importance of Hand Hygiene and Environmental Cleaning Interventions

Abstract

OBJECTIVES Hand hygiene and environmental cleaning are essential infection prevention strategies, but the relative impact of each is unknown. This information is important in assessing resource allocation. METHODS We developed an agent-based model of patient-to-patient transmission—via the hands of transiently colonized healthcare workers (HCW) and incompletely terminally cleaned rooms—in a 20-patient intensive care unit. Nurses and physicians were modeled and had distinct hand-hygiene compliance levels on entry and exit to patient rooms. We simulated the transmission of Acinetobacter baumannii, methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococci for one year using data from the literature and observed data to inform model input parameters. RESULTS We simulated 175 parameter-based scenarios and compared the effects of hand hygiene and environmental cleaning on rates of MDRO acquisition. For all organisms, increases in hand-hygiene compliance outperformed equal increases in thoroughness of terminal cleaning. From the baseline, a 2:1 improvement in terminal cleaning compared to hand hygiene was required to match an equal reduction in acquisition rates (e.g., a 20% improvement in terminal cleaning was required to match the reduction in acquisition due to a 10% improvement in hand hygiene compliance). CONCLUSIONS Hand hygiene should remain a priority for infection control programs, but environmental cleaning can have significant benefit for hospitals or individual hospital units that have either high hand hygiene compliance levels or low terminal cleaning thoroughness.

Bad Bugs, No Drugs

“…Transmission risk is magnified in the ICU compared with other healthcare settings because an average ICU patient has been estimated to receive 178 interactions with providers daily (11). Despite data showing greater efficacy reducing transmission with improvements in hand hygiene as compared with other prevention measures (12), hand hygiene rates in the ICU are reprehensibly poor, with a median compliance between 30% to 40% (13). Scrupulous adherence to hand hygiene is critical as every interaction is a potential source of transmission.…”

Routine Use of Contact Precautions for Methicillin-Resistant Staphylococcus aureus and Vancomycin-Resistant Enterococcus: Which Way Is the Pendulum Swinging?

“…2 The healthcare environment as well is a target for technology that reduces bioburden (eg, disinfection with ultraviolet-C light) and thus reduces risk of transmission. [3][4][5] Additionally, the literature describing CP's negative impact on patient care has continued to proliferate. Studies have suggested that CP may increase patient adverse events such as falls and pressure ulcers, 6,7 isolation, and depression, 8 perhaps because healthcare workers do not spend as much time in direct patient care with patients in CP.…”

The Impact of Reducing Antibiotics on the Transmission of Multidrug-Resistant Organisms

“…6 We modified an existing agent-based model of MDRO transmission developed using NetLogo version 5.0.5 software 7 that was used in a previous study. 8 (A description of the model pseudocode is provided as an online supplement.) We modeled the intensive care unit (ICU), where MDROs are prevalent and antibiotic usage is high.…”