MLVA genotyping data and cluster analysis Clustering analysis was done using the categorical and UPGMA options. The main biovars are indicated by P (Pestoides), A (Antiqua), M (Medievalis) and O (Orientalis). From left to right, the columns designate the genotype number, the number of isolates with an identical genotype, and the geographic origin of the isolates from each genotype. In three instances, indicated by asterisks (*), the strain origin was unknown. A number of classical strains available for this investigation are indicated in brackets. The Medievalis strain lacking the napA locus is indicated by **. O1 or O2a refers to the nomenclature defined by Motin et al. .