1. German-Austrian Binational Consiliary Laboratory for Listeria, Austrian Agency for Health and Food Safety (AGES), Vienna, Austria
2. These authors contributed equally
3. Division Enteropathogenic Bacteria and Legionella, Robert Koch Institute (RKI), Wernigerode, Germany
4. Baden-Wuerttemberg State Health Office, Stuttgart, Germany
5. European Programme for Intervention Epidemiology Training (EPIET), European Centre for Disease Prevention and Control (ECDC), Stockholm, Sweden
6. Bavarian Health and Food Safety Authority (LGL), Oberschleißheim, Germany
7. Hesse State Health Office, Dillenburg, Germany
8. Division for Gastrointestinal Infections, Zoonoses and Tropical Infections, Robert Koch Institute (RKI), Berlin, Germany