Fig. 1.

PCR ribotyping dendrogram of C. difficile isolates and corresponding REA groups and types. The complete dendrogram has been separated into 6 sections for print (A-F). *Isolates identified by REA group, but specific REA type not assigned (see methods). ˆHistoric BI strains isolated in the late 1980s/early 1990s, well before the BI/NAP1/027 epidemic, which started in the early 2000s. dup-two of the isolates analyzed were blinded duplicates of the same isolate. p- Plasmid accounts for a distinguishing band in the REA pattern of the whole genome HindIII digest.