1. KwaZulu-Natal, South Africa
HIV and HSV-2 risk among young women in age-disparate partnerships: evidence from
KwaZulu-Natal, South Africa
Brendan Maughan-Brown
Southern Africa Labour and Development Research Unit (SALDRU), University of Cape Town
Gavin George, Sean Beckett
Health Economics and HIV and AIDS Research Division (HEARD), University of KwaZulu-Natal
Meredith Evans
Department of Anthropology, York University, Toronto, Canada
Cherie Cawood, David Khanyile
Epicentre AIDS Risk Management, South Africa
Lara Lewis, Ayesha BM Kharsany
Centre for the AIDS Programme of Research in South Africa (CAPRISA), University of KwaZulu-Natal
Paris- 25 July, 2017

2. Background
HIV incidence is persistently high among young women in sub-Saharan Africa.
Evidence remains mixed whether age-disparate partnerships increase HIV-risk for young women.
Uncertainty regarding value of risk reduction interventions
Compounding factors suggest increased HIV risk:
Age-disparate male partners are more likely to be HIV-positive;
Riskier sexual behaviours reported within age-disparate partnerships.
Could patterns of ART uptake among men mitigate HIV-infection risk within age-disparate partnerships?
HIV testing and ART uptake positively associated with age;
Age-disparate HIV-positive partners more likely to be on ART.

3. Study aims
Primary
To assess the association between age-disparate partnerships and HIV status among year old women in a high HIV prevalence region of South Africa.
To examine whether the proportion of young women’s partners who are HIV-positive with a viral load ≥1000 copies/ml (i.e. pose a transmission risk) differs between age-disparate and age-similar partnerships.
Secondary
To assess the association between age-disparate partnerships and HSV-2 as HSV-2 is associated with increased HIV-infection risk.

4. Methods: Data HIV Incidence Provincial Surveillance System (HIPSS)
1st baseline household survey (June )
KwaZulu-Natal, South Africa
2 neighbouring regions: 1 urban, 1 rural
Random sampling of
Enumeration Areas
Households
One individual (15-49) per household
Baseline sample: N = 9812 individuals
Venous blood samples for HIV and HSV-2 tests
Face-to-face questionnaire
1st ever & 3 most recent sexual partners
Start dates of relationships
Date & result of last HIV test

5. Methods: HIV & HSV-2 among young women
Dependent variables
HIV positive (ref: HIV negative)
HSV-2 positive (ref: HSV-2 negative)
Age-disparate variables
UNAIDS definition: male partner ≥ 5 years older
Three binary measures of exposure to age-disparate relationship:
most recent partnership is/was age-disparate
at least 1 of a woman’s 3 most recent partnerships was age-disparate
at least 1 of a woman’s 3 most recent partnerships or her first-ever relationship was age-disparate
NB: partnerships (n=142) started after an HIV-positive diagnosis excluded
unrelated to HIV infection

6. Methods: HIV & HSV-2 among young women
Analysis
15-24 year old women with data on a sexual partner (N=1459)
Multiple logistic regression
Separate models for three age-disparate measures
Control measures: age, education, hh SES, #sexual partners, past HIV-testing, HIV knowledge
Weighted data & adjusted standard errors (clustering at the enumeration area level)
Young women
15-24 (n=1459)

7. Methods: HIV prevalence and viral load
among young women's partners
Data
All ongoing partnerships men reported with a woman 15 to 24 years old (N=1229)
Assumption: represent all partnerships involving 15 to 24 year old women
Young women
Men (15-49 years old) in partnership with young women aged 15-24
Dependent variables:
HIV positive
HIV+ & viral load ≥1000 copies/ml
Independent variables - 3 categories of age-disparate partners:
Men ≥5 years older
Men 5-9 years older
Men ≥10 years older (intergenerational)

8. Methods: HIV prevalence and viral load
among young women's partners
Analysis
Multiple logistic regression models
association between partnership type and HIV status and viral load of male partners
Control var: female partner age
Weighted data & adjusted standard errors
(clustering at the enumeration area level)
Young women
Men (15-49 years old) in partnership with young women aged 15-24

9. Results: age-disparate partnerships
% [95%CI]
Partnerships reported by young women
Age-disparate (5+ year gap)
Last partner
32% [28-35]
Any of last 3 partners
36% [32-40]
1st or any of last 3 partners
42% [37-46]
Partnerships (on-going) reported by men
5+ age gap
26% [22-30]
5-9 year gap
19% [16-23]
10+ year gap
7% [4-9]

10. Results: HIV & HSV-2 among young women
25%
36%
25%
37%
22%
35%
HIV+
OR [95%CI]
aOR [95%CI]
Last partner
Age-similar
ref
Age-disparate
1.62***[ ]
1.51*** [ ]
Last 3 partners
1.75*** [ ]
1.58*** [ ]
1st or last 3 partners
1.92*** [ ]
1.56** [ ]
HSV-2+
aOR [95%CI]
ref
1.65*** [ ]
1.62*** [ ]
1.80*** [ ]
***p<0.01; **p<0.05

11. Results: HIV prevalence and viral load among young women's partners
11%
27% 9%
17%
aOR: 2.92*** (95%CI: )
aOR: 2.05*** (95%CI: 1.29 – 3.26)
HIV+
HIV+ with viral load≥1000 copies/ml
aOR(95%CI)
Partnership age-gap
(ref: ≤4 years)
5-9 years
2.27***
2.01**
( )
( )
10+ years
5.50***
2.17**
( )
( )
***p<0.01; **p<0.05

12. Conclusions
Age-disparate partnerships associated with increased HIV risk
Consistent with a phylogenetic transmission network analysis conducted using a sub-sample of participants from the HIPSS study
Consistent with recent longitudinal data
Interventions to reduce HIV infection risks associated with age- disparate partnerships may help to prevent new infections among young women
Results indicate biological plausibility for the positive association
Age-disparate partners more likely to pose an HIV-infection risk
HIV-prevention among young women = early diagnosis and treatment of HIV-positive men in age-disparate partnerships
ART uptake patterns may mitigate the additional risk posed by intergenerational partnerships.
The distinction between different types of age-disparate partnerships may be less relevant when considering biological risk.

13. Acknowledgments
HIPSS sponsorship and funding Statement
HIPSS was funded by the US President’s Emergency Plan for AIDS Relief (PEPFAR) through the US Centers for Disease Control and Prevention (CDC) under terms of the co-operative agreement 3U2GGH W1
Investigators
Centre for the Programme of AIDS Research in South Africa (CAPRISA)
Epicentre AIDS Risk Management
Health Economics and HIV/AIDSs Research Division (HEARD)
Southern Africa Labour and Development Research Unit (SALDRU), University of Cape Town
HIPSS Protocol implementation and analysis
Ayesha BM Kharsany, Principal Investigator
Cherie Cawoood, Project Director
David Khanyile, Field Project Manager
Anneke Grobler, Study Statistician
Lara Lewis, Study Statistician
HIPSS Collaborating Partners
uMgungundlovu District office DOH
HAST Unit, KZN Department of Health
KZN Department of Health
National Institute for Communicable Diseases, National Health Laboratory Service (NICD/NHLS)
To all the households and individual study participants, traditional and municipal leadership, HIPSS field and office staff, all laboratory staff and PHC clinic staff in the district