Caroline Colijn is a Canadian mathematician and epidemiologist. She holds a Canada 150 Research Chair in Mathematics for Evolution, Infection and Public Health at Simon Fraser University.
Following her post-doctoral training, Colijn joined the University of Bristol's Department of Engineering Maths until 2011 when she moved to Imperial College London. While at Imperial College London, Colijn earned an Engineering and Physical Sciences Research Council Fellowship in order to study how to improve scientists ability to infer the ecological processes shaping a pathogen's evolution. In 2017, the Government of Canada announced the hiring of four Canada 150 Research Chairs, including Colijn. The program's initiative was to "enhance Canada's reputation as a global centre for science, research and innovation excellence" and Colijn's focus at Simon Fraser University was on making "connections between mathematics and public health, using diverse data to understand how pathogens adapt and spread." In February 2020, Colijn, Jukka Corander, and Nick Croucher published a study in the journal Nature Microbiology regarding vaccines. They proposed a new method for choosing the best vaccine to fight and eliminate certain bacterial strains using genomic data and mathematical modelling. During the COVID-19 pandemic in British Columbia, Colijn was awarded a Genome British Columbia grant to map the spread of COVID-19 in British Columbia. Leading a group of researchers, Colijn used the grant to measure how successful and effective British Columbia's health policy measures in lowering the risk of COVID-19. Colijn spoke favorably of the effectiveness of random testing and used mathematical modelling to project high-risk trends in the province, allowing health officers to better determine how to effectively treat the pandemic. Colijn explained that "the role of mathematical modelling in infectious disease epidemiology is to think about the data we have at the population level, groups of people, links between the groups, rates of infection and case counts, and thinking about what that means for the dynamics of this thing going forward." She was also selected to by the Chief Science Advisor of CanadaMona Nemer to sit on a country wide science expert panel to advise on COVID-19-related scientific developments. In this role, she published a research paper titled Estimating the impact of COVID-19 control measures using a Bayesian model of physical distancing, which concluded that keeping a physical distance had a direct impact on overall contact rates in the population.