Table 1.
Hospital parameters used in the simulations.
Table 2.
Baseline transmission probabilities, by ARB strain.
Fig 1.
Impact of antibiotic characteristics on acquisition of ARB.
Increase in incidence of acquisition (left axis) of (A) strain ARB-L and (B) strain ARB-H relative to no antibiotic impact, and ARB acquisitions per 100,000 patient days (PD) (right axis) for various values of an antibiotic's impact on vulnerability (V) of susceptible patients and on contagiousness (C) of colonized patients. In the simulated scenario 40% of admissions receive antibiotics and 1% of patients are colonized on admission. Note that when V = 1 and C = 1, antibiotics have no effect on acquisition, or, alternatively, no patients are receiving antibiotics.
Fig 2.
Increase in ARB acquisitions relative to no antibiotic use as antibiotic density increases.
The ARB prevalence on admission is 1%, and antibiotic impact is V = 2, C = 2. With no antibiotic use, the number of ARB acquisitions per 100,000 patient-days is 20 for ARB-L and 115 for ARB-H. The % increase in incidence (y axis) refers to these baseline rates.
Fig 3.
Individual risk for ARB acquisition.
Probability of ARB-H and ARB-L acquisition during a 6-day hospital stay for patients treated and not treated with antibiotics (left axis) and the increase in incidence relative to the scenario without antibiotic use (right axis); (A) 1% of admissions are colonized with ARB-H (B) 10% of admissions are colonized with ARB-H (C) 1% of admissions are colonized with ARB-L (D) 10% of admissions are colonized with ARB-L. Antibiotic agent impact: V = 2, C = 2.
Fig 4.
The effect of various antibiotic stewardship interventions on the daily number of ARB-H acquisitions.
Prevalence of colonization among admitted patients is 1% and 10%. The note above each bar describes a scenario; % refers to the proportion of admitted patients treated with antibiotics; type is the antibiotic agent, where the characteristics of antibiotic type A are C = 4, V = 4 and of antibiotic type B are C = 2 and V = 2; days refer to duration of treatment. Percentage inside the bar indicates reduction in acquisition relative to the reference scenario.