In order to assess the effects of Treatment as Prevention (TaP) on HIV incidence, results from HIV testing over time need to be available. This links to two aspects of information retention – data storage and data usage – which are discussed and illustrated by the case of HIV testing data in this editorial.
The ability to estimate reliable HIV incidence rate ratios (IRRs) using cross-sectional data has vast public health importance in HIV surveillance and in prevention studies; it would reduce the need to recruit and maintain large and costly longitudinal cohorts. In fact, the most common method to evaluate HIV IRR is through cohort studies which are designed to estimate HIV incidence and the effects of interventions. However, the development of biomarkers which identify recently HIV infected individuals has made it possible to estimate HIV incidence using a cross-sectional survey. Following that, one study used classical statistical methods to analyse risk factors of recent HIV infection identified with a biomarker. It is therefore important to determine how that technology can be used to estimate incidence rate ratios.
Observational studies suggest that sexual transmission of HIV may be lower in couples in which one partner is infected with HIV and the other is not (HIV-discordant couples) if the infected partner is on antiretroviral therapy (ART). If ART does confer a prevention benefit, in addition to its well established therapeutic efficacy, it may be an indication to initiate treatment earlier than currently recommended. Recently a systematic review was conducted on the issue and based on the evidence provided by one randomised controlled trial and seven observational cohort studies, ART has been shown to be a potent intervention for prevention of HIV in discordant couples. More results of the review are reported here, as well as the implications for practice and research.
Scientists at SACEMA have been in the forefront of those arguing that the time to end AIDS is now and the way to do this is through the strategic use of potent anti-retroviral therapy (ART). The road ahead will be long and hard and much still needs to be done. If we are to increase the number of people in the world who are on ART from the present 5 million to 15 million by, say, 2015 and to 30 million by 2020, many operational challenges will have to be understood and met. Here we outline the most important issues that need to be explored if treatment-as-prevention is to become a reality and if we are to end AIDS.
One question repeatedly arises at meetings in which HIV risk and prevention are discussed: should health authorities be concerned by factors that increase the per-sex-act risk of HIV infection by 2-3 fold? The rationale by some health practitioners is that the risk of acquiring HIV infection is low, in the region of 0.04% and 1.7% Read More
Network analysis has been a very helpful tool for sociologists exploring human behaviours since its emergence in the middle of the 20th century. Although many network analysis techniques have potential applications in HIV epidemiology, the statistical analysis of empirical and simulated data capturing human sexual behaviour and the spread and control of HIV most often Read More
Recently, antiretroviral drugs have been shown to dramatically reduce the risk of onward transmission from infected individuals (as ART) and also to reduce the risk of acquisition for uninfected individuals in stable relationships with infected partners (as Pre-Exposure Prophylaxis (PrEP)). This has raised many questions about how to harness these important findings for HIV prevention. Read More