title: Circulation of HIV-1 CRF02_AG among MSM population in central Italy: a molecular epidemiology-based study.
abstract: BACKGROUND
  The evolutionary and demographic history of the circular recombinant form CRF02_AG in a selected retrospective group of HIV-1 infected men who have sex with men (MSM) resident in Central Italy was investigated.
  
  
  METHODS
  A total of 55 HIV-1 subtype CRF02_AG pol sequences were analyzed using Bayesian methods and a relaxed molecular clock to reconstruct their dated phylogeny and estimate population dynamics.
  
  
  RESULTS
  Dated phylogeny indicated that the HIV-1 CRF02_AG strains currently circulating in Central Italy originated in the early 90's. Bayesian phylogenetic analysis revealed the existence of a main HIV-1 CRF02_AG clade, introduced in the area of Rome before 2000 and subsequently differentiated in two different subclades with a different date of introduction (2000 versus 2005). All the sequences within clusters were interspersed, indicating that the MSM analyzed form a close and restricted network where the individuals, also moving within different clinical centers, attend the same places to meet and exchange sex.
  
  
  CONCLUSIONS
  It was suggested that the HIV-1 CRF02_AG epidemic entered central Italy in the early 1990s, with a similar trend observed in western Europe.
authors.affiliation: Department of Infectious Parasitic and Immunomediated Diseases, Istituto Superiore di Sanità, Rome, Italy ; HIV/AIDS Unit, San Gallicano Dermatological Institute (IRCCS), Rome, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Giuliani
authors.affiliation: University of Rome Tor Vergata, Rome, Italy.
authors.forename: Maria M
authors.initials: MM
authors.lastname: Santoro
authors.affiliation: Department of Infectious Parasitic and Immunomediated Diseases, Istituto Superiore di Sanità, Rome, Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Lo Presti
authors.affiliation: Department of Infectious Parasitic and Immunomediated Diseases, Istituto Superiore di Sanità, Rome, Italy.
authors.forename: Eleonora
authors.initials: E
authors.lastname: Cella
authors.affiliation: National Institute for Infectious Diseases L. Spallanzani, Rome, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Scognamiglio
authors.affiliation: Department of Clinical Sciences, L. Sacco, University of Milan, Italy.
authors.forename: Alessia
authors.initials: A
authors.lastname: Lai
authors.affiliation: HIV/AIDS Unit, San Gallicano Dermatological Institute (IRCCS), Rome, Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Latini
authors.affiliation: National Institute for Infectious Diseases L. Spallanzani, Rome, Italy.
authors.forename: Lavinia
authors.initials: L
authors.lastname: Fabeni
authors.affiliation: National Institute for Infectious Diseases L. Spallanzani, Rome, Italy.
authors.forename: Caterina
authors.initials: C
authors.lastname: Gori
authors.affiliation: National Institute for Infectious Diseases L. Spallanzani, Rome, Italy.
authors.forename: Carmela
authors.initials: C
authors.lastname: Pinnetti
authors.affiliation: National Institute for Infectious Diseases L. Spallanzani, Rome, Italy.
authors.forename: Enrico
authors.initials: E
authors.lastname: Girardi
authors.affiliation: University of Rome Tor Vergata, Rome, Italy ; National Institute for Infectious Diseases L. Spallanzani, Rome, Italy.
authors.forename: Carlo F
authors.initials: CF
authors.lastname: Perno
authors.affiliation: Department of Clinical Sciences, L. Sacco, University of Milan, Italy.
authors.forename: Gianguglielmo
authors.initials: G
authors.lastname: Zehender
authors.affiliation: Department of Infectious Parasitic and Immunomediated Diseases, Istituto Superiore di Sanità, Rome, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Ciccozzi
mesh_terms: D001499:Bayes Theorem; D005260:Female; D015658:HIV Infections / Q000453:epidemiology / Q000235:genetics* / Q000821:virology; D015497:HIV-1 / Q000235:genetics* / Q000472:pathogenicity; D018451:Homosexuality, Male; D006801:Humans; D007558:Italy / Q000453:epidemiology; D008297:Male; D017720:Molecular Epidemiology; D010802:Phylogeny; D012189:Retrospective Studies; D012723:Sex