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RESEARCH ARTICLE
Contents Vol 8(3)

Treatment for prevention of HIV transmission in a localised epidemic: the case for South Australia

Kelly-Jean Heymer A and David P. Wilson A B
+ Author Affiliations
- Author Affiliations

A National Centre in HIV Epidemiology and Clinical Research, The University of New South Wales, Darlinghurst, Sydney, NSW 2010, Australia.

B Corresponding author. Email: dwilson@nchecr.unsw.edu.au

Sexual Health 8(3) 280-294 https://doi.org/10.1071/SH10084
Submitted: 8 July 2010  Accepted: 30 November 2010   Published: 23 May 2011

Abstract

Background: Discussion is currently taking place among international HIV/AIDS groups around increasing HIV testing and initiating earlier use of antiretroviral therapy (ART) among people diagnosed with HIV as a method to reduce the spread of HIV. In this study, we explore the expected epidemiological impact of this strategy in a small population in which HIV transmission is predominantly confined to men who have sex with men (MSM). Methods: A deterministic mathematical transmission model was constructed to investigate the impacts of strategies that increase testing and treatment rates, and their likely potential to mitigate HIV epidemics among MSM. Our novel model distinguishes men in the population who are more easily accessible to prevention campaigns through engagement with the gay community from men who are not. This model is applied to the population of MSM in South Australia. Results: Our model-based findings suggest that increasing testing rates alone will have minimal impact on reducing the expected number of infections compared to current conditions. However, in combination with increases in treatment coverage, this strategy could lead to a 59–68% reduction in the number of HIV infections over the next 5 years. Targeting men who are socially engaged with the gay community would result in the majority of potential reductions in incidence, with only minor improvements possible by reaching all other MSM. Conclusions: Investing in strategies that will achieve higher coverage and earlier initiation of treatment to reduce infectiousness of HIV-infected individuals could be an effective strategy for reducing incidence in a population of MSM.

Additional keywords: HIV, mathematical model, men who have sex with men, test and treat, South Australia.


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