1. Department of Infectious Diseases; Istituto Superiore di Sanità; Rome Italy
2. Department of Mental Health and Public Medicine, Section of Infectious Diseases; Second University of Naples; Naples Italy
3. Department of Neurosciences; Istituto Superiore di Sanità; Rome Italy
4. Department of Experimental Medicine and Surgery F. Magrassi and A. Lanzara; Second University of Naples; Naples Italy
5. Department of Infectious Diseases-Section of Hepatic Emergencies; Cotugno Hospital; Naples Italy
6. Department of Clinical Medicine and Surgery, Section of Infectious Diseases; University of Naples Federico II; Viral Infection and AIDS Unit; Naples Italy