Figure 2. Minimum spanning tree estimating the phylogenetic relationships among outbreak and nonoutbreak Listeria monocytogenes isolates from humans and from food products, southern Germany, 2012–2016. We conducted bioinformatics analyses using the Ridom SeqSphere+ software version 3.1.0-2016-01 (Ridom GmbH, Münster, Germany). The core-genome multilocus sequence typing scheme for whole-genome sequencing–based typing of L. monocytogenes relies on a set of 1,701 target genes (alleles) that are present in >99% of the known genomes of the species (7). Each circle represents an allelic profile. The numbers on the connecting lines illustrate the number of differing alleles in a pairwise comparison. Closely related genotypes (<10 allele difference) designated a cluster type and are indicated with bold red numbers. CT, cluster type; PFGE, pulsed-field gel electrophoresis.