title: Changes in circulation of B and non-B HIV strains: spotlight on a reference centre for infectious diseases in Northern Italy.
abstract: Stored demographic data and HIV RT and protease sequences of 877 HIV patients attending for the first time the HIV/AIDS outpatient clinics of a reference Infectious Diseases centre in Northern Italy between 1999 and 2006 were stratified by 3-year spanning periods according to date of HIV infection. In the period 1980--1982, new infections were entirely caused by HIV-1 subtype B strains and were all diagnosed in injection drug users, 88.9% of whom were males. Injection drug users accounted for 12.8% of new infections in 2004--2006. The frequency of heterosexually-transmitted infections consistently increased until 2000 (from almost none to 51.5%) remaining stable afterwards. About half of heterosexual patients were females. HIV infections among homosexual men increased from 0% in 1980--1982 to 15-21% between 1998 and 2006. Overall, the frequency of non-B subtypes HIV strains increased from 0% in 1980--1982 to 20.3% in 2004--2006 with a greater impact in heterosexuals (from 0% in 1980--1982 to 30.5% in 2004--2006). In conclusion, a picture of the changing scenario of circulating HIV types and subtypes in a reference Infectious Diseases centre in Northern Italy over the past 26 years is provided. A progressive modification in risk factors for HIV infection and a significant increase in the frequency of non-B HIV strains were observed.
authors.affiliation: Servizio di Virologia, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy. f.baldanti@smatteo.pv.it
authors.forename: Fausto
authors.initials: F
authors.lastname: Baldanti
authors.forename: Stefania
authors.initials: S
authors.lastname: Paolucci
authors.forename: Giovanni
authors.initials: G
authors.lastname: Ravasi
authors.forename: Anna
authors.initials: A
authors.lastname: Maccabruni
authors.forename: Alberto
authors.initials: A
authors.lastname: Moriggia
authors.forename: Giorgio
authors.initials: G
authors.lastname: Barbarini
authors.forename: Renato
authors.initials: R
authors.lastname: Maserati
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000554:Ambulatory Care Facilities; D015331:Cohort Studies; D005260:Female; D015658:HIV Infections / Q000097:blood / Q000453:epidemiology* / Q000635:transmission / Q000821:virology*; D016333:HIV Protease / Q000235:genetics; D054303:HIV Reverse Transcriptase / Q000235:genetics; D015497:HIV-1 / Q000145:classification* / Q000201:enzymology / Q000235:genetics / Q000302:isolation & purification*; D015498:HIV-2 / Q000235:genetics / Q000302:isolation & purification; D018451:Homosexuality, Male; D006801:Humans; D018445:Infectious Disease Transmission, Vertical; D007558:Italy / Q000453:epidemiology; D008297:Male; D012189:Retrospective Studies; D012307:Risk Factors; D015819:Substance Abuse, Intravenous
chemical_list: D054303:HIV Reverse Transcriptase; D016333:HIV Protease