title: Transmitted HIV Type 1 drug resistance and Non-B subtypes prevalence among seroconverters and newly diagnosed patients from 1992 to 2005 in Italy.
abstract: The patterns of transmitted drug-resistant (TDR) HIV-1 variants, non-B subtype spread, and epidemiological trends were evaluated either in seroconverters or in newly diagnosed individuals in Italy over a 13-year period. We analyzed 119 seroconverters, enrolled from 1992 to 2003 for the CASCADE study, and 271 newly diagnosed individuals of the SPREAD study (2002-2005), of whom 42 had a known seroconversion date. Overall, TDR was 15.1% in the CASCADE and 12.2% in the SPREAD study. In the 1992-2003 period, men having sex with men (MSMs) and heterosexuals (HEs) were 48.7% and 36.8%, respectively; TDR was found to be higher in MSMs compared to HEs (78.9% vs. 21%, p = 0.006). The same groups were 39.1% and 53.3% in the SPREAD study; however, no association was detected between modality of infection and TDR. Overall, 9.2% and 22.1% of individuals harbored a non-B clade virus in the CASCADE and SPREAD study, respectively. As evidence of onward transmission, 40% (24/60) of non-B variants were carried by European individuals in the latter study; among these patients the F1 subtype was highly prevalent (p = 0.00001). One of every eight patients who received a diagnosis of HIV-1 in recent years harbored a resistant variant, reinforcing the arguments for baseline resistance testing to customize first-line therapy in newly infected individuals. The spread of non-B clades may act as a dilution factor of TDR concealing the proportion of TDR in seroconverters and MSMs.
authors.affiliation: Department of Clinical Sciences 'L. Sacco' Hospital, University of Milan, Italy. chiara.riva@unimi.it
authors.forename: Chiara
authors.initials: C
authors.lastname: Riva
authors.forename: Alessia
authors.initials: A
authors.lastname: Lai
authors.forename: Ilaria
authors.initials: I
authors.lastname: Caramma
authors.forename: Stefano
authors.initials: S
authors.lastname: Corvasce
authors.forename: Michela
authors.initials: M
authors.lastname: Violin
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Dehò
authors.forename: Francesca
authors.initials: F
authors.lastname: Prati
authors.forename: Cristina
authors.initials: C
authors.lastname: Rossi
authors.forename: Maria Chiara
authors.initials: MC
authors.lastname: Colombo
authors.forename: Amedeo
authors.initials: A
authors.lastname: Capetti
authors.forename: Marco
authors.initials: M
authors.lastname: Franzetti
authors.forename: Valeria
authors.initials: V
authors.lastname: Rossini
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Tambussi
authors.forename: Massimo
authors.initials: M
authors.lastname: Ciccozzi
authors.forename: Barbara
authors.initials: B
authors.lastname: Suligoi
authors.forename: Cristina
authors.initials: C
authors.lastname: Mussini
authors.forename: Giovanni
authors.initials: G
authors.lastname: Rezza
authors.forename: Claudia
authors.initials: C
authors.lastname: Balotta
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D019943:Amino Acid Substitution / Q000235:genetics; D024882:Drug Resistance, Viral; D005260:Female; D005838:Genotype; D015658:HIV Infections / Q000175:diagnosis / Q000453:epidemiology* / Q000635:transmission / Q000821:virology*; D016333:HIV Protease / Q000235:genetics; D054303:HIV Reverse Transcriptase / Q000235:genetics; D006679:HIV Seropositivity; D015497:HIV-1 / Q000145:classification* / Q000187:drug effects* / Q000302:isolation & purification; D006801:Humans; D007558:Italy / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D017422:Sequence Analysis, DNA; D055815:Young Adult; D054302:pol Gene Products, Human Immunodeficiency Virus / Q000235:genetics
chemical_list: D054302:pol Gene Products, Human Immunodeficiency Virus; C514824:reverse transcriptase, Human immunodeficiency virus 1; D054303:HIV Reverse Transcriptase; D016333:HIV Protease; C514803:p16 protease, Human immunodeficiency virus 1