Figure 1. ApaI restriction enzyme analysis of Listeria monocytogenes outbreak strain and isolates with >90% similarity to the outbreak strain, southern Germany, 2012–2016. We performed molecular subtyping in line with the PulseNet standardized PFGE protocol for L. monocytogenes (8) and the standard operating procedures of the European Union Reference Laboratory for L. monocytogenes (9) to ensure interlaboratory comparability of the results. We analyzed PFGE patterns using BioNumerics software version 7.5 (Applied Maths, Sint-Martens-Latem, Belgium). Dendrogram indicates percentage similarity between the ApaI PFGE pattern of the outbreak strain and that of the other closely related isolates. Outbreak strain PFGE pattern is labeled with the number 54. PFGE, pulsed-field gel electrophoresis.