[1] Ist Super Sanita, Dept Vet Publ Hlth & Food Safety, I-00161 Rome, Italy
[2] Univ Bologna, Dept Vet Med, Bologna, Italy
[3] Ist Super Sanita, Natl Ctr Epidemiol Surveillance & Hlth Promot, Rome, Italy
[4] Minist Salute, Dept Prevent & Commun, Rome, Italy