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The changing face of HIV-1 diversity in Western Australia- A 12 year analysis.

The changing face of HIV-1 diversity in Western Australia- A 12 year analysis.

With Western Australia’s (WA) close proximity to countries with high a prevalence of HIV-1 and with the increase of 457, student and spouse visa holders, WA is facing a change in HIV-1 diversity. In this study we aim to monitor HIV-1 mobility in WA and to determine whether direct transmission events occur.

1183 HIV-1 sequences from 2000-2012 underwent HIV-1 subtype identification based on sequencing the protease and reverse transcriptase gene and submission to Stanford HIV drug resistant database. BIOEDIT and MEGA 5.1 software were used for phylogenetic analysis. Maximum likelihood was inferred with +100 bootstrap trees, General Time Reversible (GTR) model with gamma distributed rate of heterogeneity with invariant sites (G+I). Evidence of direct transmission was identified with a genetic distance of <1.5% and a bootstrap value of ≥98%. To determine the robustness of this framework we included multiple time point sequences, unrelated B cohort and deleted drug resistant sites.

There was limited HIV-1 diversification in WA in 2000-2005. Since 2005 we have identified an increase in C and CRF01_ AE subtypes, to the point where B subtypes marginally dominate non B subtypes 52% to 48% by 2012. We identified 27 non B (11 C, 14 CRF01_AE, 1 CRF02_AG and 1 A subtype) and 45 B clusters. Many Non B clusters appear as pairs (93%) whilst only 56% of B subtype clusters were paired. We identified 2 B-subtype clusters with 11 and 15 patients. Interestingly, one large B-subtype cluster, with known contacts, was not identified by using the analysis framework. Also interestingly, utilising unrelated B subtype sequences or deleting drug resistant sites had little impact on phylogenetic tree construction.

This study provided an insight into HIV-1 transmission dynamics in WA with the results suggesting new intervention strategies are required focusing on visa holders, travelers, MSM and heterosexuals.

Speakers: Alison Castley
Conference: ASHM 2013
Areas of Interest / Categories: AIDS 2013, Heterosexuality, HIV, Homosexuality

AIDS 2013

Clinical factors associated with suboptimal adherence to antiretroviral therapy in Asia

Adherence to combination antiretroviral therapy (cART ) plays an important role on treatment outcomes. The TREAT Asia Studies to Evaluate Resistance – Monitoring Cohort Study (TASER-M) collects patients’ adherence based on a Visual Analogue Scale. The aim of this analysis was to assess the rates of, and factors associated with, suboptimal adherence in the first 24 months of initial cART in Asian patients.

Reinvigorating evidence for action and capacity in community HIV programs (REACH Project)

REACH was a collaborative research and practice initiative to develop evidence building frameworks, capacity, tools and resources with the Victorian HIV community partnership.

The impact of immune activation on natural killer cells in the setting of HIV infection

HIV disease is associated with chronic inflammation and activation of the innate immune system. This state, as measured using plasma markers of inflammation, persists following suppression of HIV viremia using antiretroviral therapy, and may increase risk of non-AIDS co-morbidities. The causes of innate immune activation in the setting of virological suppression are unclear. Natural killer (NK) cells are innate immune cells that kill virus-infected and transformed cells without prior sensitization. We have shown that NK cells are activated both phenotypically (elevated expression of HLA-DR) and functionally (increased spontaneous degranulation measured by CD107a surface expression) in virologically suppressed (VS) HIV+ individuals. NK cells also lose expression of CD16, the receptor which mediates antibody-dependent cellular cytotoxicity.

Men who take more risks avoid HIV testing due to structural barriers

Regular HIV testing is recommended in men who take sexual risks. We assessed the relationship between perceived barriers to HIV testing, and frequency of testing among men who engaged in unprotected anal intercourse with casual partners (UAIC), to inform HIV testing strategies.

Delayed HIV diagnoses among gay and bisexual men in Australia

The majority of HIV diagnoses including delayed diagnoses in Australia occur among men who report homosexual contact – hereafter called gay and bisexual men (GBM). Delayed diagnosis is strongly associated with increased HIV-related mortality and morbidity. People who are unaware of their HIV-positive status may also be unwittingly transmitting HIV. We assessed trends in delayed HIV diagnoses among GBM in Australia.

Complex case report that illustrates the paucity of data for long term management of Visceral Leishmania-HIV co-infection.

HIV-associated leishmaniasis, endemic in the Mediterranean basin is a growing problem in India, Brazil and East Africa. Despite surviving for than 20 years, the clinical course of our visceral-leishmania (VL)-HIV co-infected patient illustrates several management challenges including diagnosis, speciation and drug resistance; monitoring burden of disease; access to and use of VL-treatments; end-organ toxicity and the combined immunosuppressive effects of HIV-VL.

Definitions of early first sexual intercourse

Early first sexual intercourse has been proposed as an important marker of later sexual and reproductive health. Discussions of what constitutes early sexual debut in this context, however, have been limited.