Healthcare-associated transmission of methicillin-resistant Staphylococcus aureus (MRSA)remains a persistent problem. The use of chlorhexidine gluconate (CHG) as a means of decolonizingpatients, either through targeted decolonization or daily bathing, is frequently used to supplementother interventions. We explore the potential of a long-acting disinfectant with a persistent effect,immediate decolonizing action in the prevention of MRSA acquisition, and clinical illness andmortality in an 18-bed intensive care unit, based on a previous model. A scenario with nointervention is compared to CHG bathing, which decolonizes patients but provides no additionalprotection, and a hypothetical treatment that both decolonizes them and provides protection fromsubsequent colonization. The duration and effectiveness of this protection is varied to fully explorethe potential utility of such a treatment. Increasing the effectiveness of the decolonizing agentreduces colonization, with a 10% increase resulting in a colonization rate ratio (RR) of 0.89 (95% CI:0.89,0.90). Increasing the duration of protection results in a much more modest reduction, with a 12-hour increase in protection resulting in an RR of 0.99 (95% CI: 0.99, 0.99). There is little evidence ofsynergy between the two.
Keywords: MRSA; decolonization; hospital epidemiology.