1. ULSS 20 Verona; Center of Community Medicine and Infectious Diseases Service; Via Germania, 20 Verona Italy 37135
2. University of Washington; Medicine; Seattle Washington USA 98108-1597
3. Università di Padova; Department of Histology, Microbiology and Medical Biotechnology; Via Aristide Gabelli, 63 PADOVA Italy 35121
4. Ospedale san Bortolo; Department of Infectious Diseases; via Rodolfi 37 Vicenza Italy 36100