HIV/AIDS – State of the Epidemic
HIV/AIDS – State of the Epidemic
Kevin M. De Cock, MD World Health Organization IAS-USA, March 14, 2008
• Global estimates and measurement • Epidemiologic parameters and their interpretation • Descriptive epidemiology by region • Descriptive epidemiology – United States • Determinants of heterogeneity • Responding to HIV/AIDS • Apologies for too many slides
The Cycle of HIV Disease
1. Incidence of HIV Infection
2. Prevalence of HIV Infection
3. Incidence AIDS
4. Prevalence of AIDS 5. Mortality from AIDS
Global Distribution of HIV Infections
Sub-Saharan Africa Asia The Americas Europe North Africa, ME Oceania 68% 14% 11% 7% 1% <1%
Estimated adult (15–49 years) HIV prevalence rate (%) globally and in Sub-Saharan Africa, 1990–2007
8 7 6
Adult HIV 4 preval ence (%)
Sub-Saharan Africa
5
3 2 1 0
1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007
Global
Year
1
Estimated number of people living with HIV globally, 1990–2007
Estimated number of people newly infected with HIV globally, 1990–2007
Millions 6 5 4
Million
40 30
Number of people 20 living with HIV 10
0
199019911992199319941995199619971998199920002001200220032004200520062007
Number of people newly infected with HIV
Upper range
3
Estimate
2
Lower range
1 0 1990 1991 1992 1993 19941995 1996 1997 1998 19992000 2001 2002 2003 2004 2005 2006 2007
Year
Year
This bar indicates the range
Estimated number of adult and child deaths due to AIDS globally, 1990–2007
Million
Global HIV Epidemiology
Sub-Saharan Africa
68% global HIV incidence and prevalence 76% global AIDS mortality Almost 90% global HIV in children One third of global burden in southern Africa; adult HIV prevalence >15% in 8 countries Clusters possible, generalized epidemics unlikely Caribbean most heavily affected, adult HIV prevalence 1%
3.0 2.5
Rest of the World
Concentrated epidemics affecting IDU, MSM, sex workers and their partners
Number 2.0 of adult and child 1.5 deaths due to AIDS 1.0
0.5 0
199019911992199319941995199619971998199920002001200220032004200520062007
Year
This bar indicates the range
Monitoring the HIV/AIDS Pandemic
HIV and AIDS case reporting
The Cycle of HIV Disease
Changing Surveillance Practice – United States
90 450
AIDS Cases & Deaths (Thousands)
70 60 50 40 30 20 10
AIDS Cases
350 300 250 200 150 100
3. Incidence AIDS 2. Prevalence of HIV Infection
Countries with concentrated epidemics: - sentinel populations (CSW, STI etc) HIV incidence is critical but difficult to measure
4. Prevalence of AIDS
Deaths
1987 1989 1991 1993 1995 Years 1997 1999 2001
50 0 2003
5. Mortality from AIDS
0 1985
Persons Living with AIDS (Thousands)
Countries with generalized epidemics: - antenatal sentinel surveillance - population surveys
1. Incidence of HIV Infection
80
Persons living with AIDS
400
2
Heterogeneity of HIV/AIDS
Impact of HIV/AIDS in Africa
Family, social, and demographic disruption Epidemic of orphans Adverse economic effects Worsening food security Worsening of public services, including health care Threatened stability and security Secondary epidemic of tuberculosis
Tuberculosis Trends in East and Southern Africa
800 700 Swaziland Lesotho Botswana South Africa Zambia Zimbabwe Kenya Malawi UR Tanzania Uganda
HIV Incidence, Prevalence and Mortality in Zimbabwe
per 100,000 pop
600 500 400 300 200 100 0
80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 0 1 2 3
Year
AIDS in Asia at End-2007
• • 4.9 million persons living with HIV; SE Asia most heavily affected Epidemics driven by IDU and commercial sex; increasing awareness of MSM Cambodia, Myanmar, Thailand show declining prevalence; Indonesia, Viet Nam increasing India – approximately 2.5 million HIV-infected; commercial sex in south, IDU in north
AIDS in Europe at End-2007
• Eastern Europe most heavily affected, 90% HIV infections in Russia and Ukraine; most in IDU • Central Europe – low level epidemic • Western Europe very heterogeneous, heterosexual transmission predominates; African immigrants affected • High or increasing rates in MSM
•
•
•
China – approximately half infections in IDU; earlier outbreak in commercial blood donors
• Declining rates in IDU in southern Europe
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HIV/AIDS in the Americas at End2007
• • • • • • US most heavily affected industrialized country - 1,039,000 1,185,000 HIV-infected 1.6 million HIV-infected in Latin America, one third in Brazil Transmission predominantly sexual in Latin America, MSM in many countries Caribbean – 230,000 HIV-infected, adult HIV prevalence 1% Three quarters of infections in Haiti and Domican Republic Predominantly heterosexual transmission, IDU in Puerto Rico and Bermuda
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Basic Reproductive Rate (Number)
• Number of secondary cases generated from one primary case • For HIV, depends on:
- Rate of partner change
- Transmissibility - Duration of infectiousness
Risk Estimates of HIV Infection in Patients Infected with HSV-2 – Meta Analysis (Wald and Link, 2002)
Impact of MC on HIV incidence: Evidence from observational studies and RCTs
Effect size Study Overall High-risk groups General Population South Africa Kenya Uganda (95% CI) 0.42 ( 0.34, 0.52) 0.29 ( 0.20, 0.42) 0.56 ( 0.44, 0.71) 0.40 ( 0.24, 0.67) 0.41 ( 0.24, 0.70) 0.49 ( 0.28, 0.86)
(Longitudinal and nested case control studies)
.15
.2
.3
.4
.5
1 1.5 Effect size
Universal Access
2005 G8 Summit at Gleneagles, Final Communiqué: “…working with WHO, UNAIDS and other international bodies to develop and implement a package of HIV prevention, treatment and care, with the aim of as close as possible to universal access to treatment for all those who need it by 2010.”
The Health Sector's Contribution to Achieving Universal Access
Expanding testing and counseling
S T R A T E G I C I N F O R M A T I O N
Maximising prevention
Accelerating treatment scale up
Strengthening health systems
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HIV Testing in France and UK
United Kingdom, 2005
• 43% of HIV-infected MSM left STI clinic undiagnosed 32% of 63,500 PLHA in UK were undiagnosed • • 34% of new HIV diagnoses at CD4 <200 per mcl • • •
Recent Guidelines on HIV Testing in Clinical Settings
France, 2004
Second highest HIV testing rate in W. Europe 40,000 (circa one third) of HIV-infected persons unaware 40% of new HIV diagnoses at AIDS or CD4 <200 per mcl
HIV in MSM, 2008…….
HIV case reports in MSM, UK
2500 HIV AIDS Deaths
Prevention of mother-to-child transmission The four-pronged strategy
• Primary prevention of HIV • Prevention of unwanted pregnancies • Prevention of transmission from HIVinfected mother to infant • Appropriate treatment and care
2000
Number of diagnoses
1500
1000
500
0
19 83 19 81 19 85 19 87 19 97 19 89 19 91 19 95 19 99 20 01 19 93 20 03 20 05
Year of diagnosis
Towards HIV-Free Survival
Rate of Gastroenteritis Hospitalizations in Early vs Delayed Weaning:
GE rate per 100 infants in age group observed 8 7 6 5 4 3 2 1 0 0 1 2 3 4 5 6 7 8 9 10 11 12 GE rate VT GE rate KiBS
Unmet treatment need in low- and middle-income countries according to region, December 2006
5 000 000 4 500 000 4 000 000 3 500 000
Number of people
68% of the total unmet need
Unmet need ARV therapy Receiving ARV treatment in Dec 2006
3 000 000 2 500 000 2 000 000 1 500 000 1 000 000 500 000 0
Sub-Saharan Africa Latin America and the Caribbean East, South and South-East Asia
•
Prolonged breast feeding is associated with increased HIV transmission; early weaning with increased infant mortality. HIVfree survival seems unchanged.
Europe and Central Asia
North Africa and the Middle East
Louis Gallait (1810 -1887) The Unhappy Mother PVSK Museum, Antwerp
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Children's access to HIV treatment, June 2006
• Africa Median: 8% • L. America Median: 8% • Asia Median: 5 %
WHO guidance on use of ARV
Evolving Challenges in Global Guidance and Practice on HIV/AIDS-2008
• Optimal regimens for PMTCT, including for breast-feeding women • When to start pediatric ART • Guidance on HIV testing in children • When to start ART in adults • Moving away from stavudine • Optimal approaches to monitoring ART • Pharmacovigilance • Access to second and third line ART regimens • Retention and adherence
Is too much money spent on AIDS?
OP-ED CONTRIBUTOR
Putting a Plague in Perspective
By DANIEL HALPERIN
Published: January 1, 2008 Last year, for instance, as the United States spent almost $3 billion on AIDS programs in Africa, it invested only about $30 million in traditional safe-water projects. This nearly 100-to-1 imbalance is disastrously inequitable….. The Global Fund's director, Michel Kazatchkine, has acknowledged, "We are not a global fund that funds local health." (New York Times, Herald Tribune)
Investing in Strategic Information
• • • • • • •
Progress towards Universal Access at December 2006 WHO/UNAIDS/UNICEF report, April 2007
Antiretroviral treatment Preventing mother-to-child transmission HIV testing and counselling Interventions for injecting drug users STI control HIV surveillance Target-setting
• "What gets measured gets done" (Margaret Chan) • "Surveillance is the conscience of any epidemic" (James W. Curran)
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