[1] IRCCS Lazzaro Spallanzani, Epidemiol Unit, Ctr Riferimento AIDS, I-00149 Rome, Italy
[2] IRCCS Lazzaro Spallanzani, Serv Epidemiol Malattie Infett, I-00149 Rome, Italy
[3] Osped San Luigi, Div Med Oncol, Catania, Italy
[4] Ctr Riferimento Oncol, Serv Microbiol & Virol, I-33081 Aviano, Italy