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Washington D.C., USA, 22-27 July 2012www.aids2012.org
Summary of Track C: Epidemiology and
Prevention Science
Audrey Pettifor, UNC
Christopher Hurt, UNC
Sheri Lippman, CAPS/UCSF
Albert Liu, SFDPH
Sinead Delany-Moretlwe, WRHI
Nora Rosenberg, UNC
Washington D.C., USA, 22-27 July 2012www.aids2012.org
The Track C Team
Washington D.C., USA, 22-27 July 2012www.aids2012.org
Key Themes and Overview
• We have effective tools• Given limited resources, how do we deliver
interventions to maximize efficiency and effectiveness so we can “Get to Zero”.– Who to target?
• Don’t know how interventions work in some populations (IDU)
– What intervention(s) to use? What combination?– How to deliver to achieve maximum coverage
and impact?
Washington D.C., USA, 22-27 July 2012www.aids2012.org
WHO TO TARGET?
Washington D.C., USA, 22-27 July 2012www.aids2012.org
Washington D.C., USA, 22-27 July 2012www.aids2012.org
Washington D.C., USA, 22-27 July 2012www.aids2012.org (Prejean et al., 2011)
MSM
Most people living with HIV will live where the wealth is concentrated
Source: McKinsey Institute, UNAIDS 2012
2 of every 3 people living with HIV will be living in urban areas by 2030
600 big cities in the world in 2025:
25% of the population 60% of the global wealth
Schwartlander.
Washington D.C., USA, 22-27 July 2012www.aids2012.org
Populations at high risk within generalized epidemics
• MSM• IDU• Sex Workers• Adolescents• Aging Populations• Transgender Persons• Discordant Couples
Washington D.C., USA, 22-27 July 2012www.aids2012.org
4.8 million young people aged 15 – 24 years are living with HIV.
3 million (two out of every three) are girls
Note: Global summary in title from UNAIDS, Together We Will End AIDS, 2012
Washington D.C., USA, 22-27 July 2012www.aids2012.org
Map of HIV prevalence among female sex workers in low-income and middle-
income countries, 2007-2011
• Pooled Odds Ratio for HIV infection among female sex workers compared to other women of reproductive age– 13.5 (95% CI 10.0-18.1)
Baral/Kerrigan et al.THAC0501
Washington D.C., USA, 22-27 July 2012www.aids2012.org
New cross-sectional measures of incidence
> 200 cells / ul
< 1.0 OD-n
> 400 copies / ml
< 80%
Classified as recently infected
CD4 cell count
BED CEIA
Avidity
HIV viral load
≤ 200 cells / ul
≥ 1.0 OD-n
≥ 80%
≤ 400 copies/ ml
Stop
Stop
Stop
Stop
•Development of assays (antibody and molecular or “HIV diversity assays”)
•Statistical modeling approaches
•Hybrids (lab + modeling)
•Incidence estimates obtained using the multi-assay algorithm
O. Laeyendecker MOAC0203
Washington D.C., USA, 22-27 July 2012www.aids2012.org
What is the right intervention(s) to use for the population(s) targeted and how do we
achieve maximal impact?
Washington D.C., USA, 22-27 July 2012www.aids2012.org
Behavioural Intervention
HIV Counselling and Testing
Coates T, Lancet 2000
Male & female condoms
Treatment of STIs
Grosskurth H, Lancet 2000
Male circumcision
Auvert B, PloS Med 2005 Gray R, Lancet 2007 Bailey R, Lancet 2007
HIVPREVENTION
combined interventions
PMTCT
Harm Reducation/Needl
e exchange
Structural /Social
Washington D.C., USA, 22-27 July 2012www.aids2012.org
The effects of MC are sustained
Time-varying Circumcision status
Conventional Cox Model
Unadjusted
Conventional Cox Model
Adjusted for Time-Varying Factors
Cox Regression with Weights from
Marginal Structural Modeling
Circumcised (vs. uncircumcised)
0.38 [0.26 – 0.55]
p<0.001
0.46 [0.31 – 0.69]
p=0.001
0.35 [0.24 – 0.51]
p<0.001
• The protective effect of MMC was sustained at 65% 66 months post intervention
Bailey R. TUAC0402
Washington D.C., USA, 22-27 July 2012www.aids2012.org
Option B+ Benefits
Source: UNICEF/BLC Discussion Paper and Methodology - Business Case for Options B/B+ , 2012
Washington D.C., USA, 22-27 July 2012www.aids2012.org
Harm reduction
• Harm reduction is working. In Amsterdam unsafe injections down and incidence declining(Grady MOAC0401)
• In Vietnam, IDUs account for 75% of all new infections. RCT of sexual risk reduction and needle-sharing intervention, needle sharing decreased from 14% at baseline to 3% at 3 months, and exhibited a durable effect (Go THAC0404).
• Modeling results of combination IDU interventions in particular high coverage sterile syringe distribution (Marshall FRLBC05)
Washington D.C., USA, 22-27 July 2012www.aids2012.org
Treatment as Prevention
• Mathematical models can help guide decision-making (Granich, Kessler, Stover, Gweshe).
• Targeting all HIV-infected persons is always the most effective strategy
• The challenge will be determining which populations to target in the short-term given limited resources: – What CD4 level? (200-350? 350-500? >500?)– Which patients? (pregnant women? discordant couples? TB
patients? IDUs? all?)
• This will depend on the epidemic context, current service delivery environment , and resources available.
HIV and STI Department, Health Protection Agency - Colindale
HIV and AIDS Reporting System
Why is HIV transmission continuing?
2006 2007 2008 2009 2010.000
5000.00010000.00015000.00020000.00025000.00030000.00035000.00040000.00045000.000 Undiagnosed
Diagnosed and untreatedDiagnosed and treated
Num
ber
livin
g w
ith H
IV
Treated5%
Untreated >50016%
Untreated 350-50012%
Untreated <3505%
Undiagnosed62%
And…
And…in 2010 only 15-25% of MSM had an HIV test
A Brown. THAC0201
Washington D.C., USA, 22-27 July 2012www.aids2012.org
Expanding Testing• Home based testing works (Carballo-Dieguez
TUPDC0304)• In South Africa by June 2011 a record
13,269,746 HIV tests were conducted. 16% tested positive of whom 48% had CD4 counts above 350 (Mbengashe THPDE0304)
• Peer testing of IDU in Thailand (Ti THAC0405)
Washington D.C., USA, 22-27 July 2012www.aids2012.org
The treatment cascade: keeping people in care
• Success in finding those lost to care in NYC using programs to trace patients out of care (Udeagu MOPDC0306)
• Programs with tracing had lower LTFU, mortality and higher retention (McMahan MOAC0302)
• Community distribution of ART in Tanzania, Uganda and Zambia reduced LTFU (Koole MOAC0305)
Washington D.C., USA, 22-27 July 2012www.aids2012.org
PrEP (like ART) works when taken
% of blood samples with tenofovir
detected
HIV protection efficacy in
randomized comparison
Partners PrEPFTC/TDF arm 81% 75%
TDF2 79% 62%
iPrEx 51% 44%
FEM-PrEP 26% 6%
There is a clear dose-response between evidence of PrEP use & efficacy
Baeten et al N Engl Med 2012Grant et al N Engl J Med 2010Van Damme et al N Engl J Med 2012Thigpen et al N Engl J Med 2012Mugo TUPL0102
Washington D.C., USA, 22-27 July 2012www.aids2012.org
Why do we need PrEP demonstration projects?
• Will MSM want PrEP?
• How will MSM use PrEP?
• How will sexual practices change?
• Where are PrEP delivery systems best located?
• Will PrEP be safe in the “real world”?
Cohen AIDS 2012
Washington D.C., USA, 22-27 July 2012www.aids2012.org
PrEP knowledge, acceptability, and potential for risk compensation
Author/Population Year PrEP Knowledge
PrEP Acceptability
Risk compensation?
Metsch et al653 MSM in Miami, DC
2011 15% Miami30% DC
48% Miami61% DC
--
Duffus et al89 seronegative partners in SD couple in South Carolina(74% heterosexual)
2010-2011
-- 94% 26% would be more likely to have unprotected sex with HIV+ partner, 27% reported would be difficult to take a daily pill
Krakower et al.Internet-based survey of 5035 MSM in North America
Dec 2010-Jan 2011
19% 50% A substantial minority of MSM anticipate risk compensation for insertive (20%) or receptive (14%) anal sex while using PrEP
Yang et al238 MSM and TG men in Northern Thailand
2012 66% 41% for MSM37% for TGs
--
The HIV Investment Framework
Reduce Risk
Reduce likelihood
of transmissio
n
Reduce mortality
and morbidity
Condoms Male
circumcision PMTCT Treatment Key populations Behavior change
BASIC PROGRAMM
E ACTIVITIES
CRITICAL ENABLERS
SYNERGIESAdapted from: Schwartlander B, et al. The Lancet, 377 (9782), 2011
Diagnosed HIV+OR, 3.00 (2.06-4.40)
Undiagnosed HIVOR, 6.38 (4.33-9.39)
Health insurancecoverage
OR,0.47 (0.29-0.77)
>200 CD4 cells/mm3 before
ART initiation OR, 0.40 (0.26-0.62)
ART adherenceOR, 0.50 (0.33-0.76)
HIV suppressionOR, 0.51 (0.31-0.83)
ART utilization/ accessOR, 0.56 (0.41-0.76)
HIV Detection
Viral Suppression
Healthcare visits
OR, 0.61 (0.42-0.90)
Lower income (<$20k)
OR, 3.42 (1.94-6.01)
(Millett, 2012)
STRUCTURAL FACTORS AFFECT RETENTION IN CARE
healthy carer AIDS-affected, abused
AIDS-affected, hungry
hungry, abused AIDS-affected, abused, hungry
0
5
10
15
20
25
30
2.1
6.67.7
10.6
20
% children 14-17 reporting transactional sex
boysgirls
Cumulative impacts of parental HIV/AIDS, abuse and hunger on child transactional sex
Cluver. WEAC0102
Modeling Community Empowerment Interventions on
Infections averted in FSW
• Combined ART and empowerment intervention may avert 16 - 40% of infections among sex workers across epidemics, assuming equal access to HIV testing and treatment
• Empowerment intervention could enable ART access among sex workers through a community-based outreach and mobilization approach
Brazil Kenya Thailand Ukraine0
4,000
8,000
12,000
16,000
20,000
Female sex workers Adults
Cumulative infections averted among FSWs and adults with scale-up of empowerment (2012-16)
A. WirtzTHAC0502
Behavioural Intervention
HIV Counselling and Testing
Coates T, Lancet 2000
STRUCTURAL
Male & female condoms
Treatment of STIs
Grosskurth H, Lancet 2000
Male circumcision
Auvert B, PloS Med 2005 Gray R, Lancet 2007 Bailey R, Lancet 2007
Treatment for preventionDonnell D, Lancet 2010Cohen M, NEJM 2011
Microbicidesfor women
Abdool Karim Q, Science 2010
Grant R, NEJM 2010 (MSM)Baeten J , NEJM 2012 (couples)Thigpen, NEJM, 2012 (Heterosexuals)
Oral pre-exposure prophylaxis
Post Exposure prophylaxis (PEP)
Scheckter M, 2002
HIVPREVENTION
combined interventions
Mugo TUPL0102
PMTCT
Harm Reduction/Needle
exchange