1. AO Policlinico di Modena, Clinic of Infectious Diseases, Modena, Italy;
2. Second University of Naples, Infectious Diseases and Viral Hepatitis Unit, Naples, Italy;
3. Department of Infectious Diseases, University of Brescia, Brescia, Italy;
4. Department of Human and Social Sciences, University of Naples L'Orientale, Naples, Italy;
5. Infectious Diseases Department, AO Ospedale Niguarda Cà Granda, Milan, Italy