1. Department of Medicine, Surgery and Dentistry University of Milan Clinic of Infectious Diseases, “San Paolo” Hospital, Milan, Italy
2. National Institute for Infectious Diseases Lazzaro Spallanzani, via Portuense, Roma, Italy
3. Dipartimento di Epidemiologia, Istituto Nazionale Per le Malattie Infettive, Rome, Italy
4. Department of Experimental Medicine and Biochemical Sciences University of Rome “Tor Vergata” via Montpellier 1, 00133 Rome, Italy
5. Research Department of Infection and Population Health, UCL Medical School, Royal Free Campus, Rowland Hill Street, London NW3 2PF, UK
6. British Columbia Centre for Excellence in HIV/AIDS Research, University of British Columbia, Vancouver, BC, Canada
7. Faculty of Medicine, Vancouver, BC, Canada