HIV Prevention Knowledge Base
Combination Approaches: An Overview of Combination Prevention
I. Definition of the Prevention Area
Combination prevention uses a mix of biomedical, behavioral, and structural interventions, and targets the prevention needs of different populations based upon epidemiologic and demographic data. Historically, programs that achieved significant, lasting improvements required change at the individual, organizational, and societal levels, providing mutually reinforcing messages and interventions.
Combination programs aim to select the optimal mix of interventions that will have the greatest impact on reducing HIV transmission, individuals’ susceptibility and vulnerability to HIV, and the infectivity of the virus.
Combination approaches can be developed for implementation at a national level, or tailored to the needs of specific at-risk populations. Programs should take into account the epidemiology, demographic patterns, and the specific context and drivers of the epidemic.
The 2009 U.S. President’s Emergency Plan for AIDS Relief (PEPFAR) Five-Year Strategy provides general guidance on working with countries to design, implement, and monitor combination HIV prevention programs that address the needs of populations in both generalized and concentrated epidemic settings.
II. Epidemiological Justification for the Prevention Area
There is no one intervention—no “magic bullet”—capable of eliminating HIV. No single prevention intervention is fully protective and each has its own strengths and limitations. HIV epidemics occur simultaneously within different populations and among people in diverse social networks, requiring a range of prevention interventions. Personal preferences also play a role, and individuals may prefer certain risk reduction options over others. Individuals often require different prevention messages and interventions at different times in their lives. For example, approaches will differ for the person just entering into sexual relations than for a discordant couple.
Momentum for combination approaches is building in regions of Southern and East Africa, where prevalence levels in the general population are disturbingly high and the best programmatic efforts have only recently begun to stabilize HIV transmission. There have been recent calls for program efforts in Southern Africa to more fully address broader social and economic factors that can increase vulnerability to HIV and AIDS. Others advocate for programs to focus on a much smaller set of high-impact interventions, to maximize resources.
In the absence of well-tailored combination prevention programs, serious programmatic gaps can occur. Even as better data become available, those engaged in national strategic planning struggle to match their programs to major at-risk populations and drivers. Within any given country, the involvement of multiple agencies, implementing organizations, and development partners in the response to HIV can result in multiple (and sometimes conflicting) messages, approaches, and a patchwork of program activities that only rarely achieve national goals. Systematic biases can also limit effectiveness; recent analyses suggest that, in generalized and concentrated epidemic settings alike, spending on prevention for most-at-risk populations is disproportionately low.
III. Core Programmatic Components
The PEPFAR Five-Year Strategy recommends a comprehensive approach to prevention that includes three types of mutually reinforcing interventions, all of which are described in more detail in AIDSTAR-One’s Prevention Knowledge Base:
- Biomedical interventions include medical approaches to block infection, decrease infectiousness, or reduce infection risk. Providers are encouraged to employ the biomedical intervention as an opportunity to engage with clients in broader prevention messaging: for example, PEPFAR recommends that clinics providing male circumcision procedures also provide risk reduction counseling.
- Behavioral interventions include a range of activities designed to encourage people to reduce behaviors that increase risk of HIV and increase protective behaviors. For example, behavioral approaches aim to delay sexual debut; reduce sexual partnerships; encourage mutual monogamy; promote correct and consistent use of condoms; and increase HIV counseling and testing. Effective approaches often employ mutually reinforcing messages at different levels. One example is an intervention to promote individual behavior change, while also encouraging families, communities and social networks to adopt and maintain healthy norms and a supportive environment.
- Structural interventions take into account social, political, and economic factors that contribute to individual risk and vulnerability. Such interventions could include efforts to change social norms that contribute to gender violence, which in turn affects women’s vulnerability to HIV, or it might include microloans to reduce dependence on sex work.
UNAIDS encourages countries to “Know Your Epidemic and Response.” Yet, often not enough is known about the social, cultural and economic drivers of HIV epidemics in the general population in seriously affected countries of Southern and East Africa. Gathering information can also be challenging in concentrated HIV epidemics, which tend to affect groups of people who are marginalized and hard to reach.
HIV epidemics are dynamic. Publicly available software packages are making it possible for countries to model common modes of transmission and to adapt outreach activities to reflect current and emerging trends.
IV. Current Status of Implementation Experience
Although the term “combination prevention” is relatively new, the concept is not new. Countries experiencing generalized epidemics routinely implement complex packages of prevention interventions; yet, geographic coverage of these interventions is often incomplete and only a minority of programs include interventions designed to address structural drivers of the epidemic. Complex programs have also existed for some time in concentrated epidemics, where service packages include biomedical, behavioral, and structural interventions; yet these approaches remain under-implemented.
The impact and efficiency of combination approaches have not yet been well studied. Prevention programs often lack adequate funding to conduct full evaluations and they rarely track costs per client, making it difficult to assess the impact and efficiency of combination programs. In addition, combination prevention programs do not readily lend themselves to experimental designs that allow outcomes to be objectively measured. It remains difficult to map causal pathways and measure the effects of simultaneous (and perhaps synergistic) prevention interventions on HIV acquisition. Data that are available, however, suggest that there is room to further strengthen many national programs.
Planning the optimal mix of behavioral, biomedical, and structural services is necessary, but not sufficient, for an effective program. Managers must implement programs of adequate scale and intensity; manage complex programs well; and monitor and evaluate their results. This has been difficult to achieve and has resulted in less effective prevention programs.
Case studies provide some information on the actions that need to be taken. Because epidemics are dynamic, as is the environment of risk, prevention programs must empower local learning and data utilization. Programs can manage complexity, but it takes serious commitment to develop management structures that support it.
Coordination and linkages are essential since no single organization or sector can support all the functions that are required. Investments must be made to develop the skills of cadres of community-level workers that link clients to the full range of services they require, and to foster community-level ownership, support decentralized decision making, and enable local-level advocacy.
Better approaches are needed to determine the optimal mix of services, calculate costs, and understand the effectiveness of programs, including methods to observe and measure synergistic effects.
Updated: March 2011
