Prevention Science Gaps and the HIVAIDS Pandemic

1
Prevention Science Gaps and the HIV/AIDS Pandemic

• Quarraisha Abdool Karim, PhD
• Head CAPRISA Women and AIDS Pogramme
• Associate Professor in Epidemiology, Columbia
  University
• Director CU-SA Fogarty AITRP
• Presentation at the XVI International AIDS
  Conference, Toronto

2
Overview

• Need for prevention research
• What works
• New Prevention Options
• Challenges and Gaps

3
Global burden Common Challenge
(conservative estimate)
Source Joint UNAIDS and WHO AIDS epidemic update
July 2006 Based on Joint UNAIDS and WHO AIDS
Update 2004
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Geographical distribution Concentrated and
generalised epidemics
Eastern Europe Central \Asia 1.6 milion IDU
Western Europe 720 000 MSM, IDU
North America 1.2 million HSex, MSM, IDU
East Asia 870 000 HSex, IDU, MSM
North Africa Middle East 510 000 HSex, IDU
Caribbean 300 000 HSex, MSM
South South-East Asia 7.4 million HSex, IDU
Sub Saharan Africa 25.8 million HSex
Latin America 1.8 million HSex, MSM, IDU
Oceania 74 000 MSM
HSex heterosexual transmission IDU
transmission through injecting drug use MSM
sexual transmission among men who have sex with
men
Source Joint UNAIDS and WHO AIDS epidemic update
December 2005
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Generalised Epidemic HIV infection in antenatal
clinic attendees in South Africa




Source Abdool Karim Abdool Karim (eds).
HIV/AIDS in South Africa, 2005
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Age and gender specific prevalence of HIV
infection in rural South Africa
Epidemiology Gender differences
10
Male
Female
8
JUN/JUL 92
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Prevalence ()
4
2
0
lt9
10-14
15-19
20-24
25-29
30-39
40-49
Source Abdool Karim Q et al, AIDS 1992
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Age specific HIV prevalence in Vulindlela
antenatal clinic attendees (2001-2004)
35 of all ANC attendees are lt20 years of age
Carrara H, Makhaye G, Frohlich J, Kharsany ABM,
Abdool Karim Q. Young women bearing the brunt of
the HIV epidemic in rural South Africa Temporal
trends in HIV infection 2001-2004. In Prep.
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Temporal changes in adult mortality rate for men
in SA
Source Dorrington R, Bradshaw D, et al. Medical
Research Council
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Temporal changes in adult mortality rate for
women in SA
Source Dorrington R, Bradshaw D, et al. Medical
Research Council
10
Correlation between Viral Load and HIV
Transmission
30
Female-to-Male Transmission
Male-to-Female Transmission
All subjects
25
20
15
Transmission rate per 100 Person-Years
10
5
0
Viral load (HIV-1 RNA copies/ml) and HIV
transmission
Source Quinn N, et al, N Eng J Med 2000
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Transmission efficiency

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HIV Prevention what works

• Sexual transmission
• ABC
• Voluntary Counselling and HIV testing
• STI reduction
• Blood borne transmission
• Harm reduction for IDUs
• SNEP
• Maintenance therapy
• Blood supply safety
• Infection control in health care
• PMTCT
• ARV PREP
• Breastfeeding alternatives
• Safe delivery

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Access to existing HIV prevention methods
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Current efficacy trials of new prevention methods
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Current efficacy trials of new prevention methods
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A Continuum of prevention research
ABC VCT STI treatment
Male circumcision Cervical barriers PREP HSV-2
suppression Maintenance therapy
Microbicides Vaccines
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Challenges and Gaps

• Knowledge of HIV status integration of
  prevention and treatment
• A continuum of prevention
• Uninfected Acutely infected established
  infection
• Bridging the gap between ABC and Vaccines
• -circumcision, barriers, HSV-2, ARVs, genital
  health, adolescent risk reduction, microbicides
• Capacity to conduct trials
• HR, Funds, Infrastructure, Cohorts
• Increasing access to what works whose
  responsibility?
• Criteria for advancing products/interventions for
  Phase III testing