1. Unit of Infectious Diseases, Department of Clinical and Experimental Medicine, ARNAS Garibaldi Nesima Hospital, University of Catania, I-95122 Catania, Italy
2. Infectious Disease Unit, Cannizzaro Hospital, I-95126 Catania, Italy
3. Infectious Diseases Unit, Gravina Hospital, I-95041 Caltagirone, Catania, Italy
4. Infectious Diseases Unit, Enna Hospital, I-94100 Enna, Italy
5. Infectious and Tropical Diseases Unit, Department of Health Promotion Sciences Maternal and Infantile Care, Internal Medicine and Medical Specialties (PROMISE), University of Palermo, I-90127 Palermo, Italy
6. Infectious Diseases Unit, Siracusa Hospital, I-96100 Siracusa, Italy
7. Infectious and Tropical Diseases Unit, Modica Hospital, I-97015 Ragusa, Italy
8. Bioinformatics Section, Department of Clinical and Experimental Medicine, University of Catania, I-95125 Catania, Italy
9. Unit of Infectious Diseases, Department of Clinical and Experimental Medicine, University of Messina, I-98124 Messina, Italy