title: Human immunodeficiency virus type 1 in Ireland: phylogenetic evidence for risk group-specific subepidemics.
abstract: HIV genetic diversity may have an impact on viral pathogenesis, transmission, response to treatment, and vaccine development. Public health surveillance that monitors the frequency and variety of HIV subtypes in a particular region or patient group is vital to successfully control the pandemic. We present the first comprehensive report on HIV diversity in Ireland. This study comprised all new HIV-1 diagnoses that were confirmed in the National Virus Reference Laboratory, University College Dublin, from January 2004 to December 2008. HIV 1 protease and reverse transcriptase sequences were generated using the Siemens Trugene HIV 1 Genotyping System. Subtypes were determined using web-based genotyping tools. There were 1579 new diagnoses [615 (39%) female and 964 (61%) male], of which 1060 had HIV-1 RNA specimens available for sequencing. Of sequenced samples, HIV-1 subtype B accounted for 50% overall, decreasing from 55.1% in 2004 to 49.5% in 2008. In addition, subtype B accounted for more than 80% of Irish-born individuals and more than 90% of Irish-born injection drug users and men who have sex with men. Subtype C was the second most prevalent in the overall cohort, accounting for 25%, although it accounted for only 6.1% of Irish-born individuals, with no evidence of in country transmission. The prevalence of non-subtype B HIV-1 infection in Ireland is increasing. However, these appear primarily to be imported infections not yet circulating within traditional Irish risk groups. Enhanced HIV-1 molecular epidemiology surveillance is required to monitor the spread of HIV-1, to inform future public health policy, and to ultimately control the HIV-1 epidemic in Ireland.
authors.affiliation: National Virus Reference Laboratory, University College Dublin, Belfield, Ireland. cfbdeg@hotmail.com
authors.forename: Cillian F
authors.initials: CF
authors.lastname: De Gascun
authors.forename: Allison
authors.initials: A
authors.lastname: Waters
authors.forename: Ciara M
authors.initials: CM
authors.lastname: Regan
authors.forename: Jane
authors.initials: J
authors.lastname: O'Halloran
authors.forename: Gillian
authors.initials: G
authors.lastname: Farrell
authors.forename: Suzie
authors.initials: S
authors.lastname: Coughlan
authors.forename: Colm
authors.initials: C
authors.lastname: Bergin
authors.forename: William G
authors.initials: WG
authors.lastname: Powderly
authors.forename: William W
authors.initials: WW
authors.lastname: Hall
mesh_terms: D000328:Adult; D005260:Female; D014644:Genetic Variation; D005838:Genotype; D016333:HIV Protease / Q000235:genetics*; D054303:HIV Reverse Transcriptase / Q000235:genetics*; D006679:HIV Seropositivity / Q000453:epidemiology* / Q000235:genetics; D015497:HIV-1 / Q000235:genetics*; D006801:Humans; D007494:Ireland / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D017720:Molecular Epidemiology; D008969:Molecular Sequence Data; D010802:Phylogeny; D011159:Population Surveillance; D015995:Prevalence; D011446:Prospective Studies; D011634:Public Health; D012189:Retrospective Studies; D012725:Sexual Behavior / Q000706:statistics & numerical data*
chemical_list: D054303:HIV Reverse Transcriptase; D016333:HIV Protease