This set of five position papers was co-commissioned by AIDSTAR-One and the STRIVE Research Consortium to address critical issues within the field of structural interventions for prevention of sexual transmission of HIV in general populations. The papers present both academic and field-based perspectives on key concepts and definitions, operational approaches, programmatic experience, and the current evidence base linking structural factors to HIV risk. Additionally, the draft resource tool provides U.S. Government (USG) teams and decision makers with guidance on prioritizing and operationalizing structural programming.
AIDSTAR-One, with support from the PEPFAR Prevention Technical Working Group, conducted in-depth interviews with implementers, policymakers, researchers, and evaluation experts that suggest that there are successes in structural interventions at the field level that can be learned from, despite the gaps and challenges. Up to now, some successes have not been adequately documented and recognized, not only because they are challenging to evaluate, but also because they cut across sectors or are implemented outside of the health sector. AIDSTAR-One and the U.S. Agency for International Development (USAID) developed this resource tool to define and describe various aspects of structural prevention interventions, particularly in generalized epidemic contexts.
In recent years, as combination prevention approaches have become the mainstay of HIV prevention responses globally, significant gaps in implementing structural interventions have been recognised [1, 2]. The discussion around structural HIV prevention has been largely informed by academic literature, but, increasingly, programmatic data are available [3-5]. Consensus on the specific definitions of structural barriers, factors, and interventions is lacking, which often causes confusion in identifying specific and appropriate interventions at the programme level, though other authors in this series attempt to address this gap . Parkhurst defines structural interventions as activities that address structural drivers (both risk drivers and environmental mediators) in a given setting . Despite challenges, HIV prevention programmers have successfully utilised existing knowledge to implement context-specific structural interventions, recognising that removing or alleviating structural barriers is likely to have long-term impact not only on HIV incidence, but also on broader development goals.
HIV incidence remains unacceptably high in sub-Saharan Africa, with 2.5 new infections for every individual placed on treatment . Combination HIV prevention therefore remains a priority. Behavioural interventions remain the cornerstone, and changes in sexual behaviour have contributed to declines in HIV incidence in some settings [2, 3]. Male circumcision reduces HIV transmission by roughly 60 percent [4, 5], and voluntary medical male circumcision (VMMC) is being scaled up in 14 sub-Saharan African countries . The global community has pledged to eliminate mother-to-child transmission . Antiretroviral treatment can reduce risk of HIV acquisition and infectivity, and thus transmission between serodiscordant sexual partners [8, 9]. Research in sub-Saharan Africa will evaluate the population-level impact on HIV incidence of strategies to expand HIV testing and offer treatment to all who test HIV-positive and, perhaps, as pre-exposure prophylaxis to uninfected individuals.
Today’s HIV prevention, care, and treatment strategies are based largely on the science and insights of biomedicine and epidemiology, two disciplines that have traditionally emphasised biological interventions and individual behaviour change over measures that address social or structural sources of risk. Most research has focused on the biological co-factors that affect transmission dynamics, such as the presence of concomitant sexually transmitted infections (STIs), the level of viral load in the bloodstream, or the use of condoms or other prevention methods that reduce the likelihood of transmission. But what about non-biological factors that influence behaviour and the likelihood of transmission, such as alcohol use immediately prior to sex, internalised stigma, economic and consumer pressures that encourage transactional sex, or exposure to violence and/or the impact of rigid gender norms? These factors also affect HIV transmission, but they operate earlier in the causal chain through more varied and complex pathways.
The last decade has witnessed remarkable progress in addressing the consequences of the HIV pandemic. In 2011, some 8 million people in low- and middle-income countries were on antiretroviral therapy (ART), marking the first time in which a majority of people eligible for treatment were receiving it . Efforts to address the causes of the epidemic, however, have not yet matched the combined speed, scale, and successes of treatment programmes. While new infections globally have steadily declined by 20 percent since peaking in 1997, HIV prevalence and incidence remains stubbornly high. In 2011, 34 million people were living with HIV and 2.5 million new infections occurred. Moreover, the epidemic’s march continues to outpace treatment efforts, with five new infections for every two people placed on therapy . Global progress also masks underlying disparities, and even reversals. While there has been remarkable behaviour change in some settings, countries in Central and South Asia, for example, have seen significant increases in new infections.
The HIV prevention field has seen remarkable progress in recent years on the biomedical front, with the promise of drug- and surgery- based prevention strategies such as male circumcision, pre-exposure prophylaxis, and early initiation of widespread antiretroviral therapy (‘test and treat’) [1–5]. Unfortunately, there have been fewer clear examples of behavioural interventions which have been shown to sustainably bring about reductions in HIV incidence [6, 7]. After 30 years of the fight against the HIV/AIDS epidemic, a number of clear lessons, however, have been learned.