AIDS Prevention in Africa’s Generalized Epidemics

AIDS Prevention in Africa’s Generalized Epidemics What should we be doing? What are we doing? A Review of HIV/AIDS Prevention in the National Strategic Planning Process In sub-Saharan Africa July 24, 2012

Sponsored by World Bank / UNAIDS (ESA) / UNFPA Norman Hearst, Allison Herling Ruark and Nicole Fraser conceptual guidance Marelize Gorgens and Helen Jackson peer review input Clemens Benedict, Helen Epstein, Daniel Halperin and James Shelton

What should we be doing? Review of scientific literatureWhat are we doing?Desk review of documents related to the national strategic planning process from 12 sub-Saharan African countriesPractical policy implications

Presentations at this Session • I will present: Methods for the first two parts of this review Results of scientific literature review • Subsequent speakers will present: Results of the NSP process review - Benedikt A practical experience (Kenya) - Ombam Policy recommendations - Gorgens • Panel discussion / questions

NSP Process Review Included countries in eastern and southern Africa with generalized HIV epidemics: Botswana South Africa Kenya Swaziland Lesotho Tanzania Malawi Uganda Mozambique Zambia Namibia Zimbabwe

Sources of Information • National Strategic Plans and Frameworks (NSP/NSF) • Know Your Epidemic/Know Your Response (KYE/KYR) and Modes of Transmission (MoT) analyses • National AIDS Spending Assessments (NASA) • United Nations General Assembly Special Session (UNGASS) Reports • Midterm reviews by UN Country Coordinators • Other associated documents • Key informants

Methods (country review) • Collect and review documents • Complete data abstraction form (guided by literature review) • Search elsewhere for missing items • Record observations and comments • “Results” are tabulations, case examples, and general process and outcome observations • Looked for common trends • Policy implications

Limitations of this Analysis • Documents often vague; specific information not always available • Documents sometimes give conflicting data • No country-by-country validation • Budgetary data often retrospective and several years old • NSPs on different 5-year cycles that don’t coincide • Plans are only plans and may not reflect reality • Many NSPs promise quick ramp-up, so situation may have improved recently (but previous NSPs also promised quick ramp-up) • Errors and judgment calls by reviewers

Scientific Literature Review(What should we be doing?) • Computerized literature search • Additional references from citations in initial publications • “Missing” key citations filled in by colleagues through vetting and peer review • DHS data analysis conducted by 2 of the authors; separate from this review • Not covered: blood safety and preventing nosocomial infection

Types of HIV epidemics • Concentrated (none of these 12 countries) Transmission in specific high risk settings or subgroups (e.g., MSM, IDU, commercial sex) drives epidemic; overall population prevalence usually low • Generalized Transmission in general population drives epidemic; can produce very high rates; mainly in Africa; “hyperepidemic” when pop. prevalence > 15% • Mixed Transmission self-sustaining both in high risk subgroups AND in general population.

HIV Transmission in Advanced Generalized HIV Epidemics in Africa(need to consider country-level differences) ῀80 % of new infections among adults 15+3 ῀20 % among children3 Blood/ injections ? Abuse ? IDU, 0-4%2 MSM (1-8%2) Vertical transmission Heterosexual transmission (81%-99% of adult infections2) Co-facilitated by low levels of male circumcision (& other biological factors) Sex work + clients + partners (3 -16 %2) Multiple including concurrent partnerships, casual sex (and partner change due to separation, widowhood etc.) Transmission within stable couples (10-38% of adult infections3) Sources: 1) UNAIDS: Global Report 2010 2) MOT analyses, 5 countries 3) Laith et al. (2012, in review) Dynamic effects Socio-economic, socio-cultural factors, gender, stigma Overstretched health systems

Levels of evidence for strategies to reduce population-wide HIV incidence in Africa’s generalized epidemics Categories: • Proven interventions • Not fully proven interventions • Interventions with Emerging Evidence • Interventions with Lack of Evidence • Disproven Interventions

Proven interventions • Proven to reduce HIV incidence at the individual level in ideal conditions (efficacy) [Usually from participants in research studies] AND • Evidence of population-level impact in real-world conditions (effectiveness) [Usually from population-based data] Only BIOLOGICAL outcomes (usually HIV rates)

Not fully proven interventions • Promising interventions for which either 1) evidence of population-level effectiveness in reducing HIV incidence exists, but evidence for efficacy of specific interventions is lacking or ambiguous, or 2) evidence of individual-level efficacy in reducing HIV incidence exists, but evidence of effectiveness in reducing HIV incidence at a population level in real world settings is lacking

Interventions with Emerging EvidenceMore recent; just a few studiesInterventions with Lack of EvidenceNot new, but lacking good evidenceDisproven InterventionsDemonstrated not to work for HIV prevention

Proven InterventionsMale Circumcision Prevention of Mother to Child Transmission (PMTCT) Interventions for Identifiable Sex Worker PopulationsNot Fully Proven InterventionsSexual behavior change (MCP) Condom Promotion Anti-Retroviral Treatment as PreventionInterventions with Emerging EvidenceEconomic Empowerment for WomenInterventions with Lack of EvidenceHIV Testing and Counseling (HTC) Interventions for Men Who Have Sex with Men Harm Reduction Interventions for Injecting Drug UsersDisproven InterventionsTreatment of Sexually Transmitted Infections (STIs)

Male Circumcision • Evidence from 3 RCTs shows lower HIV incidence among circumcised men • Strong association in generalized epidemics between level of male circumcision and population-level HIV prevalence in both men and women • Programaticexperience shows reasonable uptake in many populations

Prevention of mother to child transmission (PMTCT) • Evidence from 9 RCTs shows reduced HIV incidence among neonates through use of anti-retrovirals in perinatal period • PMTCT services have clearly reduced HIV infection among newborns in many countries • BUT little impact on wider epidemics (at least, until children would reach sexual maturity)

Interventions for Identifiable Sex Worker Populations • Trials early in the epidemic established efficacy of condom promotion and STI treatment in Nairobi, Kinshasa, etc with reduced HIV incidence in sex workers. • Public health effectiveness suggested by modeling • BUT most sex work in Africa is not in brothels or other concentrated/identifiable sites • Formal sex work is not the major driver of generalized African epidemics.

Disproven interventions STI treatment • First trial appeared to show efficacy • But 8 subsequent trials of syndromic and mass STI treatment have found no impact on HIV incidence • Important in its own right and has synergies with HIV prevention, but proven not to be effective (on the population level) for preventing HIV infection

Interventions with Lack of Evidence(in generalized epidemics) • Interventions for Men Who Have Sex with Men • Harm Reduction Interventions for Injecting Drug Users No studies with biological outcomes from generalized or mixed epidemics in Africa Individual impact may be similar to that in concentrated epidemics, but population impact likely to be much smaller

Interventions with Lack of Evidence HIV counseling and testing • Meta-analysis: those who test positive generally increase condom use; those who test negative do not (Weinhardt et al. 1999) • Three RCTs show no difference in HIV incidence in those tested (Corbett et al. 2007; Sherr et al. 2007; VCT Study Group 2000) • Testing may increase condom use among sero-discordant couples, and those who use condoms consistently have lower incidence, but “intention to treat” efficacy is not clear. • No evidence for population-level effectiveness

DHS analysis of HIV Testing(Hearst, Ruark, Green et al; not part of WB/UNAIDS/UNFPA project) • N = 48,298 in Côte d’Ivoire, Swaziland, Tanzania, and Zambia • Examined association between knowing HIV status and condom use • Knowing status only made a consistent difference for people in a stable couple who were HIV+. • BUT consistent condom use remained low, even for these people (10% to 40%).

Bottom Line on HIV Testing • An important TOOL, but NOT prevention by itself • Essential for treatment and some prevention strategies (PMTCT, ARVs for prevention) • Does not automatically or even usually result in positive behavior change • Best evidence for effectiveness is identifying discordant couples for intensive intervention and follow-up; even then, most discordant couples continue to have unprotected sex

Interventions with Emerging Evidence Economic empowerment of women • Different strategies have been tried, and more evidence is needed to establish efficacy • A community RCT which provided microfinance to poor women in South Africa found no impact on HIV incidence (Pronyk et al. 2006) • A cluster RCT in Malawi found that a conditional cash transfer to girls and young women decreased sexual activity and reduced HIV incidence by 60% (Baird et al. 2006)

Not Fully Proven Interventions Sexual behavior change(reducing MCP) • Having multiple partners is clearly an individual risk factor. • In “natural experiments,” such as in Uganda, Zimbabwe, and other African countries, significant national-level decline in HIV infections has followed changes in sexual behavior, particularly reduction in number of sexual partners among adults • Little evidence regarding the programatic impact of interventions intended to produce such behavior change • RCTs of behavioral interventions for youth have failed to show impact on HIV incidence (Cowan et al. 2010; Jewkes et al. 2008; Ross et al. 2007), though some show changes in self-reported behavior or pregnancy

Not Fully Proven Interventions Condom promotion • Male and female condoms have high efficacy, with male condoms reducing HIV transmission by 80-90% at the individual level • However the population-level effectiveness of condom promotion seems to be much less, due to low uptake and lack of correct and consistent condom use among users, risk compensation • No study has clearly shown a population-wide decrease in HIV incidence in a generalized epidemic in response to condom promotion • Some mathematical models suggest population-wide impact on HIV-incidence from condom use; others do not

Model Favoring Public Health Impact of Condoms • Modeling of epidemic in South Africa 2000-2008 (Johnson et. al. 2012) • HIV incidence in adults fell 27-31% over this period. • 23-37% of that decline may have been due to increased condom use. • Weaknesses: Results depend on model assumptions • Similar models in past projected large numbers of infections averted, even as epidemic was growing exponentially • Models are not evidence; they simply show what scenarios are plausible

DHS Data Suggest Limited Impact of Condoms in Africa (Hearst, Ruark, Green et al; not part of WB/UNAIDS/UNFPA project) • N = 48,298 in Côte d’Ivoire, Swaziland, Tanzania, and Zambia • Among people who don’t know their HIV status, is condom use protective? (People who know their status excluded from analysis in case this might cause condom use.) • Both unadjusted and adjusted analysis (age, income, urban/rural, 2+ partners in past year)

Not Fully Proven Interventions Biomedical Interventions (1) • Clinical trials suggest efficacy, but more evidence is needed to establish effectiveness in real-world settings • HIV vaccine: After several failed trials, an RCT of an HIV vaccine has shown a 31% reduction in HIV incidence • Vaginal microbicide: After a number of failed trials, the CAPRISA trial showed 39% reduction in HIV incidence and 54% among high adherers

Biomedical Interventions (2) Treatment as Prevention • Pre-exposure prophylaxis (PrEP): After several failed trials, 3 RCTs announced successful results in 2010 and 2011 • 44-73% reduction in HIV incidence treated individuals • Early ART for known discordant couples: Treatment of infected partner at CD4 350-550 reduced HIV transmission by 96% vs. treatment at CD4 < 250 (Cohen et al. 2011) • “Community viral load”: High levels of viral suppression may reduce population-wide incidence

Treatment as Prevention (cont’d) BUT • You need very high levels of treatment coverage (80+% ?), high adherence, consistent viral load suppression, excellent long term follow-up, access to second and third-line drugs • Most African countries do not have enough treatment slots to treat even people with advanced immunosuppression • Behavioral disinhibition • No evidence yet for community effectiveness in generalized epidemics

Bottom line on TasP Likely an important addition to the prevention armamentarium, but unlikely to be the “magic bullet” Even if treatment turns out to be good prevention, prevention will always be the best treatment. We will need treatment along with all the other modes of prevention for the foreseeable future. The challenge will be to make them work synergistically.

Proven InterventionsMale Circumcision Prevention of Mother to Child Transmission (PMTCT) Interventions for Identifiable Sex Worker PopulationsNot Fully Proven InterventionsSexual behavior change (MCP) Condom Promotion Anti-Retroviral Treatment as PreventionInterventions with Emerging EvidenceEconomic Empowerment for WomenInterventions with Lack of EvidenceHIV Testing and Counseling (HTC) Interventions for Men Who Have Sex with Men Harm Reduction Interventions for Injecting Drug UsersDisproven InterventionsTreatment of Sexually Transmitted Infections (STIs)

AIDS Prevention in Africa’s Generalized Epidemics