Table 1 Parameters and initial occupancy for the co-colonization model

Number of residents susceptible to any MRSA

S

350

observed

Number of residents colonized with non-USA300

I ₁

79

observed

Number of residents colonized with USA300

I ₃

14

observed

Number of residents co-colonized with non-USA300 and USA300

I _b

3

observed

Total number of residents

N

446

observed

Probability of admission of MRSA-colonized residents

_λ

0.215

estimated

Discharge rate of susceptibles (per 3 months)

γ _S

0.101

estimated

Discharge rate of MRSA-colonized (per 3 months)

γ _I

0.074

estimated

Proportion of residents colonized with non-USA300 at baseline

w ₁

0.823

observed

Proportion of residents colonized with USA300 at baseline

w ₃

0.146

observed

Proportion of residents co-colonized with both strains at baseline

w _b

0.031

observed

Acquisition rate for non-USA300^a

b _1n

 - general^b

0.029 (0.022, 0.038)

estimated

 - w/o AB^c

0.020 (0.014, 0.030)

estimated

 - with AB^d

0.042 (0.030, 0.061)

estimated

Acquisition rate for USA300^a

b _3n

 - general^b

0.006 (0.004, 0.011)

estimated

 - w/o AB^c

0.004 (0.002, 0.010)

estimated

 - with AB^d

0.009 (0.005, 0.019)

estimated

Clearance rate for non-USA300^a

g _n1

 - general^b

0.116 (0.088, 0.152)

estimated

 - w/o AB^c

0.125 (0.086, 0.179)

estimated

 - with AB^d

0.107 (0.074, 0.163)

estimated

Clearance rate for USA300^a

g _n3

 - general^b

0.137 (0.082, 0.228)

estimated

 - w/o AB^c

0.155 (0.079, 0.328)

estimated

 - with AB^d

0.125 (0.064, 0.266)

estimated