HIV Prevention Knowledge Base
Combination Approaches: An Overview of Combination Prevention
HIV Prevention Transformed: The New Prevention Research Agenda
This paper reviews developments over the last three years in HIV prevention since the 2008 Lancet series. The authors searched topics in behavioral, biomedical, and structural interventions, which together make up combination prevention, using Medline and PubMed search engines, HIV conference literature, as well as publications from international (e.g., UNAIDS) and nongovernmental organizations. The paper focuses on the most salient and current issues in the field, such as the state of the search for a vaccine, ART for prevention and its challenges, the scale up of proven prevention interventions (e.g., voluntary medical male circumcision), and an update on behavioral and structural interventions. The paper concludes and discusses the following: that the separation between biomedical and behavioral approaches is counterproductive since both rely on the other, the benefits of having more women-controlled prevention possibilities, implementation challenges to ART as prevention programs, and increasing research in implementation sciences and impact evaluations of proven interventions.
Combination Prevention: A Deeper Understanding of Effective HIV Prevention
This paper provides an overview of what combination prevention programs are and how to design and implement them to match each country’s unique social and epidemiological context. It emphasizes how HIV prevention is vital in keeping the epidemic at bay and has been a mainstay of the response since the beginning. A historical perspective to HIV prevention is provided, and how the field evolved into its current focus on combination prevention programs. UNAIDS “know your epidemic, know your response” is the starting point for planning combination prevention programs. It recommends that prevention programmers “know their epidemic” by asking where the next 1,000 infections will come from instead of focusing on past prevalence rates. “Know your response” focuses on prevention programmers designing strategies based on the current activities being implemented, compared to where the next infections will be coming from, to perform a gap analysis. The results of the gap analysis can help programmers develop a tailored approach unique to the social, cultural, and epidemiological context of a country, region, district, and/or community. The paper states that the evidence base for combination prevention programs is weak and investing in impact research as well as implementation science is vital for the continual refinement and improvement of programs. The paper concludes by stating that focusing on long-term strategies that are tailored to the immediate causes of vulnerability and underlying risk of populations is necessary to curb the rate of the epidemic.
A Decline in New HIV Infections in South Africa: Estimating HIV Incidence from Three National HIV Surveys in 2002, 2005 and 2008
South Africa conducted three nationally representative household-based surveys in 2002, 2005, and 2008. The study uses the HIV prevalence data from all three surveys to estimate incidence from 2002 to 2005 and from 2005 to 2008. The 2008 survey tested samples to detect the presence of ART drugs in the blood to determine its affect on prevalence due to longer survival. The study also measured behavioral changes in the three surveys among young women between the ages of 15 and 24. It was found that HIV prevalence in 2008 was 16.9%, and that the “excess” (increase in prevalence due to longer survival from ART) prevalence was 1.7%; therefore, HIV prevalence without the affect of ART on survival would be 15.2%. Incidence levels decreased from 2002 to 2005 and 2005 to 2008 for men and women aged 15-49 years (2.0 per 100 person-years at risk verses 1.3 per 100 person-years at risk), but were not statistically significant. The incident decrease was statistically significant for women between the ages of 15 and 24. It went from 5.5 per 100 person-years at risk from 2002 to 2005, to 2.2 per 100 person-years at risk from 2005 to 2008. Because the incident decline was mostly among young women, behavioral trends were analyzed. It was found that significant changes were found in condom use at last sex and being tested for HIV. The changes in incidence and behavior among young women were encouraging, but it should not equate to program complacency. Incident levels still need to be halved in order to meet the goals in the 2011 National Strategic Plan.
Combination HIV Prevention: Tailoring and Coordinating Biomedical, Behavioural and Structural Strategies to Reduce New HIV Infections, A UNAIDS Discussion Paper
This discussion paper outlines the advantages of implementing a combination prevention approach by using the synergies of behavioral, biomedical, and structural interventions. While there have been notable declines in prevalence and incidence linked to behavioral changes in the population, greater and more effective prevention programs must be supported to continue and improve upon these trends. The paper provides a definition of combination prevention and outlines the necessary steps in planning and implementing a coherent, evidence-based, and rights-based approach. For planning, the paper highlights issues such as having an inclusive, transparent, and evidence-informed process; identifying modes of transmission, geographic patterns, and populations; as well as developing a national plan for combination prevention. For implementation, understanding and addressing political and capacity barriers and simutaneously working on coordination, quality, and efficiency issues are essential. Lastly, in order to plan and implement effective and evidence-based interventions, investments in monitoring and evaluation must be made. Combination prevention is an attempt to address not just the individual causes of vulnerability but to target the underlying social, cultural, legal, and structural causes of vulnerability as well. Local solutions must be found and responses must be coordinated, synergistic, evidence-based, strategic, and sustained to reach the zero new infections goal found in many national HIV/AIDS strategic plans.
South African National HIV Prevalence, Incidence, Behavior and Communication Survey, 2008, A Turning Tide Among Teenagers?
This is a report on the 2008 population-based household survey (two others were conducted in 2002 and 2005). The survey examined the prevalence, incidence, behavioral, and communication differences over time. A multi-stage stratified sample was taken and about 23,000 individuals participated in the survey. A structured questionnaire was utilized to capture demographic information as well as social and behavioral information. Blood samples were drawn to determine HIV prevalence and HIV incidence. Overall, prevalence has remained stable from 2002 to 2008, and is around 11%. However, large differences were found among age groups, gender, and geographic regions. Some positive findings included a decrease in prevalence among young people who were between 15 and 24 years old (10.3% in 2005 compared to 8.6% in 2008) and, using mathematical models, incidence has decreased among young people between 15 and 20 years old. Substantial increases in condom use were observed with people between 15 and 49; 31% reported condom use at last sex in 2002 compared to about 65% in 2008. There was also an increase in youths between 15 and 24 years old being reached with communication messages. Despite these positive trends, women are still infected by HIV more than men, with the highest levels being in the 25 to 29 age group where 1 of every 3 women is infected. Intergenerational sex also increased among young women from 18.5% in 2005 to 27.6% in 2008. Therefore, while South Africa has made numerous advances to combat the epidemic, programs must continue to be strengthened and expanded.
Financing the Response to HIV in Low-Income and Middle-Income Countries
Most countries are not using their funds for HIV treatment and prevention efficiently. According to this study of 50 low- and middle-income countries, funds for prevention constituted 21 percent of all AIDS expenditures. According to UNAIDS, about 45 percent of funding should be invested in prevention. Spending on most-at-risk populations accounted for less than 1 percent in countries with generalized epidemics and 7 percent in countries with concentrated epidemics. The mismatch in the burden of risk and funding was most acute in Latin America, where 60 percent of the people living with HIV are men who have sex with men, but only 0.5 percent of funds were directed toward this group. Among the 17 low-income countries, 87 percent of their funding came from international donors.
Making HIV Prevention Programmes Work
HIV prevention programs will underperform when any of the following four issues is not appropriately addressed: targeting of risk groups; selection of programs to match the needs of risk groups; delivery and implementation of programs; and funding. Inadequate surveillance or failure to monitor and evaluate interventions can lead to programs that are mismatched for the needs of the region or country. Since quantity is often easier to measure than quality, incentive schemes have favored the former over the latter. This has resulted in situations such as the recent implementation of antiretroviral therapy in which the number of people treated was emphasized over changes in patients’ life expectancy.
Behavioural Strategies to Reduce HIV Transmission: How to Make Them Work Better
Behavioral strategies, such as programs to encourage condom use or to reduce or eliminate sex with non-primary partners, can be difficult to sustain and should be combined with other strategies (biomedical and structural) to effect population-level changes. Promoting behavioral change in the absence of structural change can be particularly difficult, for example, when drugs or alcohol are central to a country’s economy. Monitoring and evaluation (M&E) of programs should be integrated into local programs; current M&E projects are often conducted largely in high-income countries with uncertain relevance to lower-income countries. Four key steps to achieving behavioral change are described.
Structural Approaches to HIV Prevention
Structural factors (economic, social, political, environmental) can affect HIV risk. For example, gender inequality is linked to unprotected sex. That could be due to male control of finances or due to male physical violence, causing some women to submit to unprotected sex out of fear of physical violence or fear of losing financial support. Although the outcome is the same in either case, the necessary interventions differ. Financial problems could be addressed by micro-loans and changes in inheritance laws that treat men and women unequally. Male violence might be addressed by programs exploring concepts of masculinity. Monitoring and evaluation of structural approaches can be difficult since such programs don’t readily lend themselves to experimental design; the authors give recommendations for program assessment.
The History and Challenge of HIV Prevention
The history of HIV is traced from June 5, 1981, when the disease was first announced by the U.S. Centers for Disease Control and Prevention, to the present. Biomedical, epidemiologic, political, and activist history provides insights into an era of tremendous discovery; obstacles; and social and political ferment. Although the disease was first recognized in men, women now constitute 61 percent of adults living with HIV in sub-Saharan Africa. Projections about the course of the disease were often wrong. The most successful early prevention efforts didn’t come from the medical or public health communities, but from people living with HIV and from combination programs that addressed structural, biomedical, and behavioral issues simultaneously.
Biomedical Interventions to Prevent HIV Infection: Evidence, Challenge, the Way Forward
Several biomedical interventions have proven efficacy; the benefits of other medical interventions are less clear. According to a Cochrane review, male condoms are 85 percent effective in preventing transmission of HIV. However, long term compliance, especially with primary partners, tends to wane. Disinhibition – or an increase in risky behaviors associated with a sense of being protected – is a problem with this and several other interventions. Male circumcision is estimated to be 58 percent effective, and has the benefit of being a one-off commitment. However, circumcised men also reported increased numbers of sexual partners. The benefits and limitations of female condoms, cervical barriers, treatment of sexually transmitted infections, vaccines, topical and oral antiretroviral prophylaxis, and microbicides are discussed.
Coming to Terms with Complexity: A Call to Action for HIV Prevention
Despite widespread knowledge about the transmission of HIV, approximately 7,000 people are newly infected each day. The impact of combination programs is complex and can cause unexpected consequences. For example, HIV infection in men who have sex with men in Bangkok, Thailand, paradoxically increased in 2005 as sex venues were closed – driving men into illegal settings for sex. There is no single “magic bullet” intervention, and combination prevention approaches are as necessary as combination treatment of HIV. Globally, about 85 percent of HIV transmission is sexual. The promise and limitations of current combination interventions for youth, high-risk groups, and women are discussed.
Reassessing HIV Prevention
Nine countries in southern African—where more than 12 percent of adults are infected with HIV—account for two-thirds of infections globally. In these generalized epidemic settings, emphasis has been placed on condom promotion and distribution, voluntary counseling and testing (VCT), and treatment of other sexually transmitted infections (STIs). The authors review the evidence and find that the assumptions driving this choice of HIV prevention strategies are largely unsupported, concluding that the largest donor investments are being made in interventions that will fail to deliver large-scale impact. Greater focus on two promising interventions, male circumcision and reducing multiple sexual partnerships, is suggested.
Expert Think Tank Meeting on HIV Prevention in High-prevalence Countries in Southern Africa Report
Southern Africa is home to 40 percent of all people living with HIV globally. The Southern African Development Community, with support from UNAIDS, USAID, WHO and other organizations, convened a meeting of 38 participants to analyze the drivers of the epidemic and to make recommendations for stepped-up prevention. Key drivers identified included multiple and concurrent partnerships; low levels of circumcision; and sexual violence. Factors underlying the drivers were identified, such as wealth disparities and high population mobility. The report includes recommendations to address the drivers of HIV and their causes; key priorities and processes; and monitoring and utilizing resources.
Evaluation of Large-Scale Combination HIV Prevention Programs: Essential Issues
This commentary provides guidance on how to plan and implement evaluations to determine the impact of combination prevention interventions. The authors note the numerous challenges in conducting evaluations for combination prevention programs, but stress the importance in surpassing these to design a solid study. Challenges that are described include the need to have large population sizes and long time lengths if HIV incidence is the outcome of interest; absence of a naïve control group and ethical considerations with having a control group; and poor outcome surrogates (i.e., measures on self-reported behaviors, sexually transmitted infections, and pregnancy) cannot replace outcomes such as HIV incidence, prevalence, and infections averted. Large-scale evaluations should consider the following: defining the evaluable package, deciding if the evaluation is to study each individual intervention verses the entire package, choosing a “control” or “comparison” group in the study design, finding a reliable assay to measure HIV incidence when one is currently lacking, deciding on various methods in one study, and providing shorter-term outcomes on longer-term goals. In conclusion, a strong evidence base is crucial for combination prevention programs. The HIV community is open to the challenge and is supporting it through current evaluations.
The Future of HIV Prevention
According to the authors, prevention strategies have historically been categorized as either behavioral or biomedical. Behavioral interventions have included strategies for condom promotion, partner reduction, and cash transfers to keep young women in school or choose partners close to their own age. Biomedical prevention strategies include the use of antiretrovirals and vaccines (when they become available) to reduce or eliminate infectiousness, and to prevent mother-to-child transmission. The authors note that strategies considered strictly biomedical often include behavioral elements, such as retention in care and adherence to prescribed regimens. They highlight the recent success of using antiretrovirals to prevent new infections and describe some of the challenges that remain in implementing this methodology with population-level effectiveness, including acute and early infections, drug-resistant variants of HIV, and concerns about adherence and long-term use of antiretroviral regimens. The authors encourage further implementation research on how best to increase demand and retention, improve adherence, and prevent behavioral disinhibition. The authors endorse combination prevention, where biomedical, behavioral, and structural interventions are implemented concurrently. They stress the need for assessing large, complex, heterogeneous prevention programs to identify cost-effective, efficient, and effective strategies that improve health outcomes. At the broader systemic level, they endorse the use of implementation science on cost-effectiveness to guide decision makers with limited resources.