Fig 1. Repartition of the clusters according to the links identified between the patients.

Clusters are represented by unique identification numbers. Next to the cluster number, the number of patients for who an epidemiological link was detected is indicated (i.e. 2/3: two of the three patients included in the cluster present this link). f: familial link; o: same geographic origin; p: geographic proximity. Clusters in orange contain more than 3 patients and cluster in grey more than 6. The purple boxes indicate the number of clusters belonging to each category (or combination of categories) of links. The blue boxes indicate clusters comprising exclusively Belgian-born patients. The green boxes indicate clusters with strains presenting the 776000000000171 spoligotype (S-family).