Even in Australia, the prevalence and incidence of HIV infection is as high in some MSM communities as it is in resource-poor countries [22]. There is the potential to identify cohorts of these gay men, at high risk of HIV infection, of sufficient size to enable the conduct of HIV prevention trials [4]. Prevention research in both resource-poor and

resource-rich settings is necessary. Population-specific information on effectiveness and acceptability is essential to provide guidance for policy makers and health-care providers [24]. Here we explore whether subpopulations with sufficiently high incidences of HIV infection for HIV prevention trials can be readily identified in a low HIV incidence setting such as Australia, by assessing incidence in cohort subgroups,

and analysing data on willingness to participate in trials. The Ibrutinib molecular weight HIM study was a community-based prospective cohort study of HIV-negative homosexually active men in Sydney conducted as a vaccine preparedness cohort study [25]. The methodology for the HIM study has been published previously [26,27]. The study HDAC inhibitor recruited participants from June 2001 to December 2004. Interviews were conducted from June 2001 to June 2007. Written informed consent was obtained from all potential study participants prior to enrolment. The HIM study received ethics approval from the University of New South Wales. All participants underwent annual structured face-to-face interviews on a wide range of topics, including sexual relationships and practices and injecting drug use. Serological testing for HIV was performed annually using a combined antigen/antibody test (AxSYM, HIV Antigen/Antibody Combo; Abbott Diagnostics, Abbott Park, IL, USA). At approximately 6 months between annual face-to-face interviews, information on sexual relationships and practices and injecting drug use in the past 6 months was collected via a short version telephone

interview. Quantitative sexual behaviour data were Dapagliflozin collected. Printed HIV prevention information was available for study participants in the interview waiting area, but no formal HIV risk reduction counselling was provided during the study. Incident HIV infections were identified through diagnoses at the annual study visit and by linkage with the national HIV register. The final match against the national HIV register and the final study interviews occurred in June 2007. HIV seroconversion was identified through matching for 13 participants and, for these individuals, no behavioural data were available at the time of estimated infection. For seven participants in whom the estimated date of infection was less than 12 months after the last interview, information obtained from the last interview was carried forward for risk factor analysis. Six participants whose estimated dates of infection were more than 12 months later were excluded from risk factor analysis. Statistical analysis was performed using stata 10.