Figure.

Epidemiology and phylogeny of an outbreak of MRSA sequence type 2371

(A) Epidemiological map of 14 infants on the SCBU (patients 1–14). (B) Phylogenetic tree based on whole-genome sequencing of MRSA isolates from patients 1–14. (C) Epidemiological map of patients 1–14 and ten other patients (patients 16, 17, and 19–26) with linked MRSA infection detected in the community; coloured lines link members of the same family. (D) Phylogenetic tree based on whole-genome sequencing of MRSA isolates from patients 1–14 and patients 16, 17, and 19–26. (E) Epidemiological map of all cases of MRSA identified by whole-genome sequencing, and one patient (patient 18) suspected of being linked to the outbreak but for whom no MRSA colonisation was detected. (F) Phylogenetic tree of all cases of MRSA in the outbreak; 20 individual MRSA colonies from a staff member are shown in red boxes, with multiple colonies from the staff member shown in parentheses. Boxes shown for infants on SCBU in panel A represent duration of hospital stay (black boxes show infants included by the infection-control investigation and white boxes show infants excluded by the infection-control team). Grey vertical blocks in A, C, and E show times on the SCBU when there were no known carriers of MRSA. MRSA=meticillin-resistant Staphylococcus aureus. SCBU=special care baby unit. SNP=single-nucleotide polymorphism. P=patient.*Out-group was the sequence type 22 reference genome.