The impact of interventions on HIV transmission at the level of stable discordant partnerships

1. The impact of interventions on HIV transmission at the level of stable discordant partnerships HiamChemaitelly, Timothy Hallett, & Laith J. Abu-Raddad Infectious Disease Epidemiology Group Weill Cornell Medical College – Qatar Cornell University Qatar Foundation - Education City Doha, Qatar

2. Background Discordant partnerships are a key target for HIV prevention efforts and subject of epidemiologic studies and clinical trials

3. Key question What is the impact of multiple prevention interventions on HIV incidence among stable discordant partnerships?

4. What is the fraction of discordancy among partnerships affected by HIV? Preliminary results Half of stable partnerships affected by HIV are discordant

5. What is the contribution of HIV incidence among discordant partnerships to all HIV incidence? Preliminary results Close to half of HIV incidence appears to be occurring among discordant partnerships

6. Methodology for assessing the impact of interventions • Mathematical model incorporating extensive uncertainty & sensitivity analyses • Simulation of intervention packages and clinical trials • Applied to the Bushenyi, Uganda cohort of 1003 stable discordant partnerships

7. Methodology • Input parameters including interventions’ efficacy, adherence, eligibility, and coverage • Four kinds of interventions: HAART, condoms with or with no access to couple-based VCT, male circumcision, & PrEP • Impact of interventions separately and in combination

8. Interventions’ parameters

9. HAART assuming partial adherence but full eligibility and coverage

10. Comparing interventions at partial adherence but full eligibility and coverage

11. Comparing interventions at full and partial eligibility & coverage

12. HAART: varying eligibility & coverage

13. Additive effects of interventions (absence of synergy)

14. Implementation of 2 interventions simultaneously at full eligibility & coverage

15. Implementation of 3 interventions simultaneously at full eligibility & coverage

16. Implementation of 4 interventions simultaneously at full eligibility & coverage

17. Conclusions: HIV prevention among discordant partnerships • Efficacious interventions that can reduce HIV incidence exist. Yet, all interventions are partially efficacious • Adherence, eligibility and coverage play as important a role as biological efficacy of intervention for partially efficacious interventions • HAART whether independent or in combination with other interventions has the highest potential in reducing HIV incidence • HIV prevention among discordant partnerships will have a significant impact on HIV incidence but it is not the magic bullet that will control HIV incidence in sub-Saharan Africa

18. Announcement:Open positions at Weill Cornell Medical College – Qatar • If you are: • A highly qualified and strongly motivated biostatistician and/or epidemiologist • With a solid record of scientific research and publications • Interested in joining a forefront and leading research group • We offer • Competitive compensation packages • Ivy league medical school and high-profile research experience • Contacts • Infectious Disease Epidemiology Group • Email: ideg@qatar-med.cornell.edu • URL: http://qatar-weill.cornell.edu/research/faculty/abuRaddad/InfectiousDiseaseEpidemiologyGroup.html