Background HIV-1 non-B subtypes have recently entered Western Europe following immigration from other regions. The distribution of non-B clades and their association with demographic factors, over the entire course of the HIV-1 epidemic, have not been fully investigated in Italy. Methods We carried out a phylogenetic analysis of HIV-1 pol sequences derived from 3670 patients followed at 50 Italian clinical centres over nearly three decades. Results Overall, 417 patients (11.4%) carried non-B subtypes. The prevalence of non-B strains increased from 2.6% in 1980–1992 to 18.9% in 1993–2008 (Po0.0001) in a subset of 2479 subjects with a known year of diagnosis. A multivariate analysis on a subset of 1364 patients for whom relevant demographic data were available indicated that African ethnicity, heterosexual route of infection and year of diagnosis were independently associated with non-B HIV-1 infection (P 0.0001). All pure subtypes, except for clade K, and seven circulating recombinant forms were detected, accounting for 56.6 and 34.1% of the non-B infections, respectively. The F1 subtype was the most prevalent non-B clade among Europeans and was acquired heterosexually in half of this patient population. Unique recombinant forms accounted for 9.4% of the non-B sequences and showed a B/F1 recombination pattern in one-third of cases. Conclusions The circulation of non-B clades has significantly increased in Italy in association with demographic changes. Spread of the F1 subtype and B/F recombinants appears to predominate, which may result in a redistribution of the relative proportions of the different strains, and this could lead to overlapping epidemics. Thus, the HIV-1 landscape in Italy may in future be distinct from that of the rest of Europe.
|Titolo:||ANDAMENTO DELLA PREVALENZA IN ITALIA DEI CEPPI NON-B DI HIV-1 NEGLI ULTIMI TRENT'ANNI|
|Data di pubblicazione:||21-dic-2010|
|Parole Chiave:||HIV-1 ; NUOVA DIAGNOSI DI INFEZIONE DA HIV ; RICOMBINANTI ; SOTTOTIPI ; VARIANTI|
|Settore Scientifico Disciplinare:||Settore MED/17 - Malattie Infettive|
|Citazione:||ANDAMENTO DELLA PREVALENZA IN ITALIA DEI CEPPI NON-B DI HIV-1 NEGLI ULTIMI TRENT'ANNI ; relatore: Massimo Galli. - Milano : Università degli studi di Milano. Universita' degli Studi di Milano, 2010 Dec 21. ((23. ciclo, Anno Accademico 2010.|
|Digital Object Identifier (DOI):||10.13130/caramma-ilaria-chiara_phd2010-12-21|
|Appare nelle tipologie:||Tesi di dottorato|