Understanding the Potential Impact of a Combination HIV Prevention Intervention in a Hyper-Endemic Community

Global Health, University of Washington, Seattle, Washington, United States of America.
PLoS ONE (Impact Factor: 3.23). 01/2013; 8(1):e54575. DOI: 10.1371/journal.pone.0054575
Source: PubMed


Despite demonstrating only partial efficacy in preventing new infections, available HIV prevention interventions could offer a powerful strategy when combined. In anticipation of combination HIV prevention programs and research studies we estimated the population-level impact of combining effective scalable interventions at high population coverage, determined the factors that influence this impact, and estimated the synergy between the components.

We used a mathematical model to investigate the effect on HIV incidence of a combination HIV prevention intervention comprised of high coverage of HIV testing and counselling, risk reduction following HIV diagnosis, male circumcision for HIV-uninfected men, and antiretroviral therapy (ART) for HIV-infected persons. The model was calibrated to data for KwaZulu-Natal, South Africa, where adult HIV prevalence is approximately 23%.

Compared to current levels of HIV testing, circumcision, and ART, the combined intervention with ART initiation according to current guidelines could reduce HIV incidence by 47%, from 2.3 new infections per 100 person-years (pyar) to 1.2 per 100 pyar within 4 years and by almost 60%, to 1 per 100 pyar, after 25 years. Short-term impact is driven primarily by uptake of testing and reductions in risk behaviour following testing while long-term effects are driven by periodic HIV testing and retention in ART programs. If the combination prevention program incorporated HIV treatment upon diagnosis, incidence could be reduced by 63% after 4 years and by 76% (to about 0.5 per 100 pyar) after 15 years. The full impact of the combination interventions accrues over 10–15 years. Synergy is demonstrated between the intervention components.

High coverage combination of evidence-based strategies could generate substantial reductions in population HIV incidence in an African generalized HIV epidemic setting. The full impact could be underestimated by the short assessment duration of typical evaluations.

Download full-text


Available from: Ramzi A Alsallaq, Oct 07, 2014
  • Source
    • "But they are also needed for interventions conceptualized primarily at the individual level. As part of a “combination” approach, interventions that seek to address social drivers can provide support for biomedical interventions [7, 8]. Moreover, individual-level interventions may unintentionally have social impacts, for example, by stigmatizing marginalized groups [52]. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Introduction Contemporary HIV-related theory and policy emphasize the importance of addressing the social drivers of HIV risk and vulnerability for a long-term response. Consequently, increasing attention is being given to social and structural interventions, and to social outcomes of HIV interventions. Appropriate indicators for social outcomes are needed in order to institutionalize the commitment to addressing social outcomes. This paper critically assesses the current state of social indicators within international HIV/AIDS monitoring and evaluation frameworks. Methods We analyzed the indicator frameworks of six international organizations involved in efforts to improve and synchronize the monitoring and evaluation of the HIV/AIDS response. Our analysis classifies the 328 unique indicators according to what they measure and assesses the degree to which they offer comprehensive measurement across three dimensions: domains of the social context, levels of change and organizational capacity. Results and discussion The majority of indicators focus on individual-level (clinical and behavioural) interventions and outcomes, neglecting structural interventions, community interventions and social outcomes (e.g. stigma reduction; community capacity building; policy-maker sensitization). The main tool used to address social aspects of HIV/AIDS is the disaggregation of data by social group. This raises three main limitations. Indicator frameworks do not provide comprehensive coverage of the diverse social drivers of the epidemic, particularly neglecting criminalization, stigma, discrimination and gender norms. There is a dearth of indicators for evaluating the social impacts of HIV interventions. Indicators of organizational capacity focus on capacity to effectively deliver and manage clinical services, neglecting capacity to respond appropriately and sustainably to complex social contexts. Conclusions Current indicator frameworks cannot adequately assess the social outcomes of HIV interventions. This limits knowledge about social drivers and inhibits the institutionalization of social approaches within the HIV/AIDS response. We conclude that indicator frameworks should expand to offer a more comprehensive range of social indicators for monitoring and evaluation and to include indicators of organizational capacity to tackle social drivers. While such expansion poses challenges for standardization and coordination, we argue that the complexity of interventions producing social outcomes necessitates capacity for flexibility and local tailoring in monitoring and evaluation.
    Full-text · Article · Aug 2014 · Journal of the International AIDS Society
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Objective: For antiretroviral therapy (ART) to have a population-level HIV prevention impact, high levels of HIV testing and effective linkages to HIV care among HIV-infected persons are required. Methods: We piloted home-based counseling and testing (HBCT) with point-of-care CD4 count testing and follow-up visits to facilitate linkage of HIV-infected persons to local HIV clinics and uptake of ART in rural KwaZulu-Natal, South Africa. Lay counselor follow-up visits at months one, three and six evaluated the primary outcome of linkage to care. Plasma viral load was measured at baseline and month six. Results: 671 adults were tested for HIV (91% coverage) and 201 (30%) were HIV-infected, of which 73 (36%) were new diagnoses. By month three, 90% of HIV-infected persons not on ART at baseline had visited an HIV clinic and 80% of those eligible for ART at baseline by South African guidelines (CD4≤200 cells/μL at the time of the study) had initiated ART. Among HIV-infected participants who were eligible for ART at baseline, mean viral load decreased by 3.23 log10 copies/mL (p<0.001) and the proportion with viral load suppression increased from 20% to 80% between baseline and month six. Conclusions: In this pilot of HBCT and linkages to care in KwaZulu-Natal, 91% of adults were tested for HIV. Linkage to care was ∼90% both among newly-identified HIV-infected persons as well as known HIVinfected persons who were not engaged in care. Among those eligible for ART, a high proportion initiated ART and achieved viral suppression, indicating high adherence and reduced infectiousness.
    Full-text · Article · May 2013 · JAIDS Journal of Acquired Immune Deficiency Syndromes
  • [Show abstract] [Hide abstract]
    ABSTRACT: The newest data related to the Human Immunodeficiency Virus (HIV) / Acquired Immune Disease Syndrome (AIDS) epidemic is primarily positive, but many areas of the world, especially Sub-Saharan Africa, remain disproportionately affected. Between 2005 and 2007, three large randomized trials evaluating circumcision for prevention of HIV acquisition in heterosexual African males showed a reduction in the rate of acquisition of HIV by up to 66 % over 24 months. Since the results of these studies were published, global health organizations have ramped up efforts to help target countries to provide male circumcision delivery services in sub-Saharan Africa. Male circumcision (MC) is cost-effective and efficacious, especially when used in combination with other prevention strategies. Available data shows good acceptability amongst target populations. Neonatal circumcision is well tolerated and more cost effective than adult male circumcision and should be included as part of MC initiatives in the future. Behavioral disinhibition and risk compensation are important factors that may mitigate the rate of risk reduction conferred by male circumcision and should be further investigated. As delivery of male circumcision services is expanded, the issues affecting the female sexual partners of the target population must be outlined and addressed. Whether or not the results of the African trials can be extrapolated to warrant expansion of MC programs to other populations is a critical area for further study.
    No preview · Article · Jun 2013 · Current Urology Reports
Show more