1. 1Istituto Zooprofilattico Sperimentale dell'Umbria e delle Marche ‘T. Rosati’, Perugia, Italy
2. 2Istituto Superiore di Sanità, Rome, Italy
3. 3European Programme for Public Health Microbiology Training (EUPHEM), European Centre of Disease Prevention and Control (ECDC), Stockholm, Sweden
4. 4National Reference Laboratory for Listeria monocytogenes, Istituto Zooprofilattico Sperimentale dell’Abruzzo e del Molise 'G. Caporale', Teramo, Italy
5. 5Azienda Sanitaria Unica Regionale Marche – Area Vasta 2, Ancona, Italy
6. 6Agenzia Regionale Sanitaria Marche, Ancona, Italy