Infectious disease epidemics among men having sex with men (MSM) in Canada

In Progress

Access to Medications

HIV/Sexually Transmitted and Blood-borne Infections

When examining the transmission of HIV, it is important to consider sexual mixing patterns (the difference/similarity in risk of HIV infection between two sexual partners) and seroadaptive practice (when people decide whether to engage sexually with each other based on both partners’ HIV statuses).

Given that both PrEP (a preventative medication for those at high risk for HIV) and sexual mixing patterns influence HIV epidemics among men who have sex with men (MSM), it is necessary to examine how one may affect the other. However, little is known in this area specific to the MSM population in Canada.

Our results could be used to inform and help ensure that PrEP programs are effective – reaching the right people at the right time, and protecting MSM in Canada from HIV infection.

Study 1: Population-level sexual mixing by HIV status and pre-exposure prophylaxis (PrEP) use among MSM in Montréal, Canada: implications for HIV prevention

Using cross-sectional survey data of MSM in Montréal, Canada, we will:

  • Quantify population-level serosorting by comparing observed partnership distribution by HIV status to that expected by chance
  • Quantify population-level serosorting among HIV-negative MSM stratified by PrEP use
  • Quantify population-level PrEP-matching by comparing observed partnership distribution by PrEP use to that expected by chance

Study 2: Modeling PrEP and in the influence of sexual mixing patterns on HIV epidemics among MSM

This sub-project uses a dynamic, compartmental HIV-transmission model among gay, bisexual, and other MSM living in an urban setting in Canada to estimate:

  1. The influence of baseline serosorting patterns on the potential transmission impact of PrEP
  2. The influence of PrEP-mediated change in serosorting on the transmission impact of PrEP
  3. Its sensitivity to epidemiologic and intervention (PrEP effectiveness and coverage) conditions

Study 3: Modeling the cost-effectiveness of PrEP in Toronto

This is a systematic review which evaluates the cost-effectiveness of PrEP in high-income settings.

Access to Medications

HIV/Sexually Transmitted and Blood-borne Infections

Dr. Sharmistha Mishra

An infectious diseases physician and Canada Research Chair in Mathematical Modeling and Program Science, Dr. Sharmistha Mishra is an international leader in mathematical modelling and epidemiology of HIV and other STIs.


  • Dr. Joseph Cox (McGill University)
  • Dr. Daniel Grace (University of Toronto)
  • Dr. Trevor A. Hart (University of Toronto & Ryerson University)
  • Jody Jollimore (Community-Based Research Centre for Gay Men’s Health)
  • Dr. Nathan J. Lachowsky (University of Victoria)
  • Dr. Gilles Lambert (Institut national de santé publique du Québec)
  • Dr. David M. Moore (British Columbia Centre for Excellence in HIV/AIDS & University of British Columbia)
  • Dr. Syed W. Noor (Ryerson University)


  • Jesse Knight
  • Huiting Ma
  • Dr. Nasheed Moqueet
  • Linwei Wang


  • Canadian Institutes for Health Research
  • CIHR Canadian HIV Trials Network
  • Canadian Foundation for AIDS Research
  • Canadian Blood Services
  • Ontario HIV Treatment Network
  • Ryerson University
  • Public Health Agency of Canada


  • Herak Apelian (McGill University)
  • Dr. Heather Armstrong (British Columbia Centre for Excellence in HIV/AIDS)
  • Dr. Stefan Baral (Johns Hopkins University)
  • Marc Messier-Peet (McGill University)
  • Ricky Rodrigues (Ryerson University)

Contact Info

Kristy Yiu

Research Coordinator

(416) 864-6060 ext. 77372