1. epidemic in South Africa
The evolving HIV
epidemic in South Africa
Salim S. Abdool Karim, MBChB, PhD
and
Quarraisha Abdool Karim, PhD

2. The authors
Salim S Abdool Karim, MBChB, PhD, is a clinical infectious diseases epidemiologist whose current research interests are in microbicides and vaccines to prevent HIV infection and implementation of antiretroviral therapy in resource constrained settings.
Quarraisha Abdool Karim, PhD, is an infectious diseases epidemiologist whose current research interests are in understanding the evolving HIV epidemic in South Africa; factors influencing acquisition of HIV infection in adolescent girls; and sustainable strategies to introduce HAART in resource-constrained settings.
Salim Abdool Karim is Deputy Vice-Chancellor (Research) and Professor of Public Health at the University of Natal in Durban, South Africa. He is also Professor in Clinical Epidemiology at the Mailman School of Public Health at Columbia University and Adjunct Professor of Medicine at the Weill Medical College of Cornell University. He is Director of CAPRISA – Centre for the AIDS Program of Research in South Africa.
Quarraisha Abdool Karim is an Associate Professor of Epidemiology at the Mailman School of Public Health at Columbia University. She is also an Honorary Associate Professor of Public Health and Family Medicine at the Nelson R Mandela School of Medicine, University of Natal, South Africa. She is an Executive Committee member of CAPRISA. In addition, she co-ordinates the Columbia-University Southern African Fogarty AIDS International Training and Research Programme

3. Learning objectives At the end of this lecture the student will:
Be able to define transmission dynamics of HIV
Have an understanding of the evolution of the HIV
epidemic in South Africa through 5 distinct periods
Know the distinct features of the South African HIV
epidemic
Gain knowledge of the essential interventions against
HIV/AIDS.

4. Transmission dynamics
Prevalence
- How much disease at a point in time
- Existing infected people
Implications for health impact
Indicates the need for health care
Incidence rate
- New infections in those without the infection
- Rate at which new infections are acquired
over a period of time
More sensitive for assessing growth of epidemic
Sensitive marker of effect of interventions
The prevalence and incidence rates are calculated as follows:
number of individuals who are infected with HIV at a specific time
Prevalence =
number of individuals in the population at that point in time
number of new cases of HIV during a certain time period
Incidence rates =
Prevalence reflects the situation at one point in time, while incidence measure the rate at which the infection is spreading. The two measures are complementary ans together provide an understanding of the dynamic changes in an epidemic

5. South Africa's HIV/AIDS epidemic
About 10% of global burden of infection
Major and Minor epidemic
Distinctive features of major epidemic
- Prior to 1987 HIV infection rare in general pop
- High prevalence
- Highest rates of infection in young women
- Predominantly subtype C
South Africa is home to about 10% of the global burden of HIV infection. Since the first reported cases of AIDS in South Africa, both a major and minor epidemic has evolved.
The minor epidemic was a well circumscribed epidemic caused by subtype B HIV and occurred predominantly in gay men and haemophiliacs. It started in the early 1980s and by 1990 was already on the wane. The major epidemic is caused by subtype C HIV and is spreading heterosexually in the general population. The major epidemic has already reached high prevalence rates in excess of 25% and the highest rates are in young women.
Source: Abdool Karim Q, Abdool Karim SS. South Africa: Host to a new and emerging HIV epidemic. Sex Trasm Inf 1999; 75:
Abdool Karim Q, Abdool Karim SS. Epidemiology of HIV infection in South Africa. AIDS 1999; 13: S4 - S7.

6. HIV Infection in ANC attendees in South Africa40 30
HIV prevalence (%) 20 10
Five distinct phases mark the evolution of the HIV epidemic in South Africa:
i. Pre-1987: localised clade B epidemic
ii : generalised clade C epidemic starts
iii : explosive epidemic and low mortality
iv : Incidence high but stable and mortality
rising rapidly
v. Post 2002: AIDS-related mortality rates climb until they exceed the HIV incidence rates resulting in an observed decline in HIV prevalence
1988
1990
1992
1994
1996
1998
2000
2002
Source: National Department of Health, Pretoria, South Africa

7. Introduction of HIV in SA: Pre 1987
1982 – First reported cases of AIDS
Epidemic largely limited to:
- Men who have sex with men
- Transfusion recipients and
- Haemophiliacs
Clade B
The first reported cases of AIDS in South Africa occurred in This “minor” epidemic was largely limited to men who have sex with men; blood transfusion recipients and haemophiliacs. Infection with subtype B HIV was dominant.

8. HIV infection in selected groups from 1985 - 1987
Year
Province
Group N %
1985
KwaZulu Natal
Rural community
441
1986
Transvaal
Miners
17 021
0.01
Sex workers
1 200
1987
Antenatal women
500
Outpatient
268
Studies in rural and urban communities as well as health care services showed that HIV was rare in the general population prior to 1998.
Source: Abdool Karim SS. Making AIDS a notifiable disease- is it an appropriate policy for South Africa? S Afr Med J, 1999; 89:
Dusheiko GM. Regional prevalence of hepatitis B, delta, and human immunodeficiency virus infection in southern Africa: a large population survey. Am J Epidemiol. 1989; 129(1):

9. HIV Infection in ANC attendees in South Africa40 30
HIV prevalence (%) 20 10
Phase 2: Generalised epidemic begins
The major epidemic as a result of heterosexual spread of HIV is associated with a concomitant epidemic in infants born to HIV infected mothers.
The period marks the beginning of the generalised or “major” epidemic of Clade C HIV infection in South Africa.
This exponential increase in HIV infection had a doubling time of approximately 15.1 months.
1988
1990
1992
1994
1996
1998
2000
2002
Source: Department of Health

10. Age and gender distribution of HIV infection
in South Africa 10
Male
JUN/JUL 1992
Female 8 6
Prevalence (%) 4 2
Population-based surveys undertaken during this period demonstrate, in addition to the rapid rise in HIV infection, the striking difference in age and gender distribution of HIV infection.
The figure illustrates the early rise of infection in young women between the ages of years compared to a later rise of infection in men at about age years. The high incidence rates in young women is a key factor driving the spread of HIV in South Africa during this period.
<9
10-14
15-19
20-24
25-29
30-39
40-49
Source: Abdool Karim Q, Abdool Karim SS, Singh B, Short R, Ngxongo S. Prevalence of HIV infection in Rural South Africa. AIDS 1992; 6:

11. HIV Infection in ANC attendees in South Africa40 30
HIV prevalence (%) 20 10
Phase 3: Explosive spread of HIV
The period is the most critical period in the evolving HIV epidemic in South Africa. This period marks the explosive growth in HIV transmission fuelled by high incidence rates in young women and the coalescence of genetically diverse epidemics. Ironically this period coincided with the establishment of democracy in South Africa.
1988
1990
1992
1994
1996
1998
2000
2002
Source: Department of Health

12. HIV incidence rates in a cohort of sex workers in KwaZulu-Natal
Year
Person-months of follow-up
Incidence Rate (%); 95% CI
1996/97
996
16.8 ( )
1998
1644
18.2 ( )
1999
780
20.0 ( )
Overall ( )
3420
18.2 ( )
This period of rapid growth in the HIV epidemic was marked by very high incidence rates. In one trial, follow-up of several hundred sex-workers in the KwaZulu-Natal Province of South Africa showed an average incidence rate of 18.2 per 100 women-years over the period from 1996 to 1999.
Source: Abdool Karim SS, Ramjee G and Gouws E – Data from COL-1492 trial

13. Prevalence and incidence of HIV: Hlabisa clinic
attendees aged 15-49:
Year N
Prev(%)(95% CI)
Incidence %
1992
884
4.2 ( )
2.0
1993
709
7.9 ( )
3.3
1995
314
14.0 ( )
7.1
1997
4731
27.2 ( )
10.2
1998
3166
29.9 ( )
10.5
1999
3001
34.0 ( )
10.3
2001
906
36.1 ( )
Data from rural women attending antenatal clinics in one district of KwaZulu Natal Province of South Africa shows the rapid growth in the epidemic during this period, due largely to the high incidence rates creating large numbers of newly infected people within the population.
Source: Williams BG, Gouws E, Wilkinson D, Abdool Karim SS. Estimating HIV from Age Prevalence data e epidemic situation. Statistic in Medicine 2000.

14. Temporal trends in the age-specific prevalence of HIV
infection in antenatal clinic attendees in Hlabisa
Age Group
1992
1995
1998
2001
20-24
6.9%
21.1%
39.3%
50.8%
25-29
2.7%
18.8%
36.4%
47.2%
30-34
1.4%
15.0%
23.4%
38.4%
35-39
0.0%
3.4%
23.0%
This analysis of HIV prevalence in each age group band over 3-year cycles, knows how HIV prevalence grew from 6.9% in 1992 to 50.8% in 2001 among young girls in the rural area of KwaZulu Natal.
Source: Wilkinson D, Abdool Karim SS, Williams B, Gouws E. High HIV incidence and prevalence among young women in rural South Africa: developing a cohort for Intervention Trials. J Acquir Immune Defic Syndr 2000; 23:

15. HIV Infection in ANC attendees in South Africa40 30
HIV prevalence (%) 20 10
Phase 4:
The period epitomises the maturation of the major HIV epidemic in South Africa characterised by the epidemic reaching saturation. The HIV prevalence is almost static, masking the rapidly rising mortality and continued high incidence rates.
1988
1990
1992
1994
1996
1998
2000
2002
Source: Department of Health

16. Prevalence among antenatal clinic attendees by
Province 1999 – 2001 10 20 30 40
KwaZulu- Natal
Mpumalanga
Gauteng
Free State
North West
East Cape
Limpopo
Northern Cape
Western Cape
Province
Prevalence (%)
1999
2000
2001
This figure demonstrates the stabilisation of HIV prevalence by province. While KwaZulu-Natal continues to be at the epicentre and the gradient of infection from east to west coast continues, there is stabilisation in HIV prevalence across most of the nine provinces of South Africa.
Source: Dept. Health – 12th National HIV and Syphilis Sero-prevalence survey of women attending
public antenatal clinics in South Africa 2001

17. Tuberculosis caseload and antenatal HIV prevalence
in Hlabisa district
Tuberculosis is the most common presenting opportunistic infection associated with advancing HIV disease. The figure illustrates how the TB burden in one rural community has increased as the HIV prevalence has increased.
The high prevalence of HIV infection during this period is indicative of the demand for health care to be anticipated in the next period as individuals progress to AIDS.
Source: Hlabisa Hospital Records

18. AIDS in King Edward Hospital -1998
54% of Medical in-patients were HIV+
84% of HIV+ met WHO AIDS case criteria
56% HIV+ co-infected with tuberculosis
Case fatality rates: HIV+ = 22% vs HIV- = 9%
HIV/AIDS now dominates medical practice in South Africa. At a tertiary hospital, more than half the patients were HIV infected in A case fatality rate has also more than doubled since the pre-HIV era.
Source: Colvin M, Dawood S, Kleinschmidt I, Mullick S, Lalloo U. Int J STD AIDS 2001,

19. Age specific mortality rate
1985 baseline for men 50
100
150
200
250
300
350
PERCENTAGE OF AVERAGE
Mortality rates in are already beginning to rise among men. The increase is predominantly in the year age group.
15-19
20-24
25-29
30-34
35-39
40-44
45-49
50-54
55-59
60-64
65-69
AGE
Source: Dorrington R, Bourne D, Bradshaw D, Laubscher R, Timæus IM. The Impact of HIV/AIDS on Adult Mortality in South Africa. MRC Technical Report

20. Age specific mortality rate
1985 baseline for women
3.500
3.000
2.500
1994
2.000
1996
Ratio
1997/8
1.500
1998/99
1999/2000
1.000
0.500
The situation in women is substantially worse. Mortality rates in young women have quadrupled since the start of the epidemic, especially in young women between the ages of years.
0.000
15-19
20-24
25-29
30-34
35-39
40-44
45-49
50-54
55-59
60-64
Age
Source: Dorrington R, Bourne D, Bradshaw D, Laubscher R, Timæus IM. The Impact of HIV/AIDS on Adult Mortality in South Africa. MRC Technical Report

21. Conclusion Current epidemic phase has 5 parallel effects:
- Continuing large numbers of new HIV infections
- Ongoing high mother-to-child transmission rates
- Rising morbidity and its impact on health services
- Rapidly rising deaths
- Increase in numbers of orphans
Essential to intervene with:
- Prevention of new infections
- PMTCT programmes
- Care including OI prophylaxis and ARV treatment
- Social services for families impacted by AIDS deaths
- Programs and social services for orphans

22. Conclusion
HIV affecting mainly young women in SA, highlighting the importance of:
- interventions targeting youth
- addressing gender inequity
- greater involvement of men in prevention programs
South Africa is experiencing a devastating epidemic

23. Acknowledgements Sources of Data
- National Department of Health, Pretoria, South Africa
- Debbie Bradshaw, South African Medical Research Council
- Rob Dorrington, University of Cape Town
Brian Williams, WHO, Geneva
Eleanor Gouws, WHO, Geneva
Cheryl Baxter, CAPRISA