1. Unit of Infectious Diseases, Department of Clinical Medicine, Ospedale “dell’Angelo”, 30174 Venice, Italy
2. Unit of Infectious Diseases, Department of Clinical Medicine, Ospedale Civile “S.S. Giovanni e Paolo”, 30122 Venice, Italy
3. Unit of Microbiology and Virology, Department of Medical Direction, Ospedale “dell’Angelo”, 30174 Venice, Italy