Providing a conceptual framework for HIV prevention cascades and assessing feasibility of empirical measurement with data from east Zimbabwe: a case study

Abstract

SummaryBackgroundThe HIV treatment cascade illustrates the steps required for successful treatment and is a powerful advocacy and monitoring tool. Similar cascades for people susceptible to infection could improve HIV prevention programming. We aim to show the feasibility of using cascade models to monitor prevention programmes.MethodsConceptual prevention cascades are described taking intervention-centric and client-centric perspectives to look at supply, demand, and efficacy of interventions. Data from two rounds of a population-based study in east Zimbabwe are used to derive the values of steps for cascades for voluntary medical male circumcision (VMMC) and for partner reduction or condom use driven by HIV testing and counselling (HTC).FindingsIn 2009 to 2011 the availability of circumcision services was negligible, but by 2012 to 2013 about a third of the population had access. However, where it was available only 12% of eligible men sought to be circumcised leading to an increase in circumcision prevalence from 3·1% to 6·9%. Of uninfected men, 85·3% did not perceive themselves to be at risk of acquiring HIV. The proportions of men and women tested for HIV increased from 27·5% to 56·6% and from 61·1% to 79·6%, respectively, with 30·4% of men tested self-reporting reduced sexual partner numbers and 12·8% reporting increased condom use.InterpretationPrevention cascades can be populated to inform HIV prevention programmes. In eastern Zimbabwe programmes need to provide greater access to circumcision services and the design and implementation of associated demand creation activities. Whereas, HTC services need to consider how to increase reductions in partner numbers or increased condom use or should not be considered as contributing to prevention services for the HIV-negative adults.FundingWellcome Trust and Bill & Melinda Gates Foundation.

Will the global HIV response fail gay and bisexual men and other men who have sex with men?

“…We used this approach to highlight low service utilization for each intervention type [16], acknowledging the following: 1) the heterogeneity of prevention needs represented among diverse groups of men who have sex with men; and 2) the complex web of interacting HIV prevention modalities [17]. The number of participants who tested for HIV and received results served as the denominator for determining steps along the cascade.…”

Application of the HIV prevention cascade to identify, develop and evaluate interventions to improve use of prevention methods: examples from a study in east Zimbabwe

“…Earlier analyses of Manicaland Cohort data on risk among AGYW indicated unprotected sexual relationships with older men contribute to their high HIV incidence . Preliminary analyses of the HIV prevention cascade for other prevention methods among AGYW found gaps in perceptions about personal HIV infection risks . Lack of risk perception indicates lack of motivation to use HIV prevention methods.…”

“…VMMC is central in Zimbabwe's HIV prevention programme, but only 10% of men (15- circumcised in Manicaland [23] and uptake is off-track to meet national targets [28]. Previous HIV prevention cascade analysis using Manicaland Cohort data found that low VMMC uptake in the study population was largely due to low risk perception for HIV infection, suggesting gaps in motivation and poor local availability [2]. Motivation for VMMC uptake can be affected by negative perceptions of its consequences.…”

Monitoring the AIDS Response: How Can Lessons from the Pre-2015 Era Inform Monitoring Progress Towards Ending the AIDS Epidemic by 2030?

“…1), besides critical enablers and synergies with other development sectors. Inspired by the 90-90-90 target for testing and treatment [19][20][21], recent work has proposed CASCADE analyses for monitoring and managing primary prevention programmes [22]. In addition, future monitoring will need to harness the power of new technologies, allowing the electronic collection of data from all health facilities and all community-based service delivery platforms as well as from commodity distribution systems (e.g.…”