1. Section of Infectious Diseases, Department of Clinical Medicine and Surgery, University of Naples Federico II, 80131 Naples, Italy
2. Department of Public Health and Infectious Diseases, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy
3. Infectious Diseases Department, Azienda Ospedaliero Universitaria Policlinico Umberto I, 00161 Rome, Italy