1. Epidemiologic trends in HIV infection among men who have sex with men in Ontario: The situation in 2003
Robert S. Remis, Maraki Fikre Merid
Ontario HIV Epidemiologic Monitoring Unit
Department of Public Health Sciences
University of Toronto
Gay Men’s HIV Prevention Summit
AIDS Bureau, Ontario Ministry of Health and Long-term Care Toronto, Ontario, March 17-18, 2004

2. Background
MSM seriously affected by HIV epidemic since the beginning (late 1970s)
Many developments have influenced trends in the epidemic since then:
Education, information and prevention
Identification of HIV in 1984
HIV test developed late 1985
Antiretroviral drugs,
HAART 1996-

3. Objectives
To examine trends in incidence and prevalence of HIV infection among MSM in Ontario
To assess trends in HIV testing
To examine recent increasing trends in number of HIV diagnoses and interpret observations

4. Methods: Data sources HIV diagnostic data Laboratory Enhancement Study
Detuned assay
Repeat testers
Reported AIDS cases
HIV-related mortality

5. Methods: Data analysis
HIV model: incidence and prevalence of
HIV infection
HIV diagnoses
AIDS
HIV-related mortality
Dr. Robert S. Remis
Public Health Sciences, University of Toronto

6. Reported AIDS cases for selected exposure categories, 1981-2002

7. First-time HIV diagnoses (adjusted) for selected exposure categories,1985-2002

8. First-time HIV diagnoses among MSM by health region, 1985-2002

9. First-time HIV diagnoses (adjusted) MSM, by quarter, 2000-03

10. Number of HIV tests (adjusted) MSM, 1992-2002

11. HIV incidence among MSM repeat testers, with 95% CLs, 1992-2001 (30,881 PY)
Source: Polaris Seroconversion Study

12. HIV incidence among MSM repeat testers by age group, 1992-99
Source: Polaris Seroconversion Study

13. HIV incidence from detuned assay MSM by health region, Oct 1999 – Dec 2002
Source: Laboratory Enhancement Study

14. HIV incidence from detuned assay MSM by region by period, Oct 1999 – Dec 2002
Source: Laboratory Enhancement Study

15. Modeled HIV incidence among MSM Ontario, 1977–2002
Dr. Robert S. Remis
Public Health Sciences, University of Toronto

16. Modeled HIV prevalence among MSM Ontario, 1977–2002
Dr. Robert S. Remis
Public Health Sciences, University of Toronto

17. Modeled MSM population at risk, HIV prevalence and incidence by health region, Ontario, 2002
Dr. Robert S. Remis
Public Health Sciences, University of Toronto

18. Modeled HIV prevalence and number diagnosed by exposure category, 2002
Dr. Robert S. Remis
Public Health Sciences, University of Toronto

19. Conclusions Gay men in Ontario continue to be severely
affected by the HIV epidemic
HIV prevalence: 15% (regional variation:10 -20%)
HIV incidence (i.e. new infections) not decreasing and likely increasing
Trends in risk behaviour elsewhere are consistent with trend in HIV incidence
Reasons for persisting high incidence unclear: treatment optimism? safe-sex fatigue?

20. Conclusions
Observed increase in new HIV diagnoses in 2002 of particular concern
May be due to:
increased HIV testing or
increased HIV incidence

21. Conclusions
Likely due, at least in part, to increased HIV incidence since:
increase in HIV+ tests > increase in tests
proportion identified as seroconverters by linked tests or serologic evidence is stable
incidence in repeat testers increasing (data not shown)
data from elsewhere and syphilis epidemic evidence for increased risky sexual behaviour

22. Acknowledgements
AIDS Bureau, Ontario Ministry of Health and Long-Term Care
Frank McGee, coordinator
HIV Laboratory, Central Public Health Laboratory
Carol Swantee, diagnostic data
Keyi Wu, programming
Jane Njihia
Laboratory Enhancement Study
Chris Archibald, CIDPC, Health Canada
Ontario HIV Treatment Network