Oliver Gatalo, PhD candidate, Dalla Lana School of Public Health

Supervised by Sharmistha Mishra, Temerty Faculty of Medicine and Rafal Kustra, Dalla Lana School of Public Health

Project Title: Limiting biases in measures of vaccine effectiveness from real-world data during evolving outbreaks: a systematic review and simulation study of mpox

Project Summary: Mpox caused a global outbreak in 2022, disproportionately affecting gay, bisexual, and other men who have sex with men. Vaccines were deployed based on historical data suggestive of biological efficacy before data on real-world vaccine effectiveness (VE) was available. Outbreaks rapidly declined, and mathematical models are now being used to quantify the potential role of vaccines in local outbreak control, using estimates from real-world studies. But real-world data may have confounders - e.g., when individuals at high-risk for mpox are more likely to get vaccinated - which could lead to systematic errors in VE measures. I will systematically review data on real-world VE against mpox infection to explore how, and why, VE measures might vary across studies (Aim-1). I will then design a simulation model of an mpox outbreak to explore the influence of potential confounders, like that described above, on VE measures using the simulated data as a proxy for real-world data (Aim-2). Outcomes could guide adjustments to real-world VE, which in turn would help parse the impact that vaccines may have had on recent mpox outbreaks and provide stronger grounding for how much population-level immunity may exist when mpox re-emerges. Thus, this research will support pandemic readiness.