Circulation of HIV-1 CRF02_AG among MSM population in central Italy: a molecular epidemiology-based study.
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ABSTRACT: Introduction
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.
SUBMITTER: Giuliani M
PROVIDER: S-EPMC3863479 | biostudies-literature | 2013
REPOSITORIES: biostudies-literature
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