Outbreak R0 Boston, USA (1721) 4.3 Burford (1758) 3.4 Chester (1774) 5.8 Warrington (1773) 4.0-5.3 Paris, France (1766) 4-5 London (1836-1870) ∼ 5 Kosovo (1972) 10.8 Europe (1958-1973) 10-11

Our dataset -  10 years -  308,102 patients -  8,507 wards -  3,185,710 links -  1,261 positive MRSA cases -  21 strains

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Summary -  Even though the hospital system is

hierarchically organized, the ward network is too random to predict risk wards efficiently.

-  In-flow better predictor than static measures.

-  There is a detectable response—patients move to low-degree wards.