In Canada, more than 50,000 cardiac arrest (i.e. “heart attack”) patients simultaneously suffer from brain injury due to reduced brain blood flow and oxygen delivery. Primary brain injury occurs following the initial reduction in brain blood flow following cardiac arrest, and in some cases, secondary brain injury occurs after brain blood flow is restored to normal levels. However, the physiological mechanism(s) responsible for secondary brain injury following cardiac arrest remain unclear, and the data available in humans are very limited. We hypothesize that a key contributor to secondary brain injury following cardiac arrest is due to consequential activation of the human body’s innate immune system, which signals for excess brain inflammation and results in cellular damage. The proposed investigation, which will be conducted at Vancouver General Hospital, aims to measure key biological markers to quantify brain inflammation in post cardiac arrest patients. The findings from this study will improve our overall understanding of the mechanism(s) that contribute to brain injury characterized by reductions in blood flow and will potentially identify potential therapeutic targets and improve quality of life in these patients.
Research Pillar: Clinical Research
Determination of the optimal SARS-CoV-2 vaccination strategy to achieve a robust and long-lasting immune response
Global COVID-19 vaccine distribution has been inequitable, with high-income countries afforded widespread access to vaccines and boosters, while among the low-income countries only 2 percent of individuals are vaccinated. Consequently, over 50 percent of the world’s population remains unvaccinated. Fortunately, however, data from vaccinated cohorts can inform the most efficient and effective community-level vaccination strategies for the unvaccinated populations. Currently approved mRNA vaccines were initially tested with dosing intervals of 21-28 days; however, this may lead to suboptimal immunity. Further, data informing the optimal timing and frequency of booster doses is lacking. This project will answer critical questions regarding the optimal vaccination strategies to achieve a robust long-lasting immune response. In this study I will employ data from a prospective national cohort of adult paramedics, providing sociodemographic data and serum blood samples. I will identify the optimal vaccination strategies to achieving a robust immune response at 12, 18 and 24 months, including examining differences between sex, race, and age. These data will inform ongoing global vaccination efforts, to maximize efficiency and long-term protection.
End of Award Report – June 2025
Results
My project led to several important findings that have helped improve how we understand and manage COVID-19, especially for frontline workers like paramedics. One major result was showing how immunity from COVID-19 vaccines can decrease over time. This helped inform decisions on when people should get booster doses to stay protected—an issue that was especially important for high-risk groups in British Columbia.
We also found that bivalent booster vaccines—which target both the original virus and newer variants—produced stronger immune responses than earlier vaccines. This helped guide vaccine policies and gave reassurance that updated vaccines were working better for people on the front lines. Another exciting part of the research was studying how many vaccines people had and how that affected their immunity against newer variants like Omicron. We also looked into a theory called antibody imprinting to understand how previous exposure to the virus or vaccines might shape future immune responses. These findings offered new insights into how the immune system remembers and reacts to COVID-19.
In addition, we explored the link between COVID-19 infections and long-term symptoms among vaccinated paramedics. This helped raise awareness of post-COVID or “long COVID” issues, even among people who had been vaccinated. My work didn’t just stay in academic journals—it was shared with public health officials and helped improve how COVID-19 is managed among paramedics and other healthcare workers in BC and across Canada. The results also have broader value for similar workers across North America.
Impact
The research supported by my partnered award has already made a meaningful impact on public health in British Columbia and beyond. Our findings have helped guide decisions about when booster COVID-19 vaccines should be given and provided evidence supporting the use of bivalent booster vaccines to strengthen protection, especially among frontline healthcare workers like paramedics.
My work has also raised awareness of long COVID symptoms among vaccinated individuals and contributed to improving occupational health policies for high-risk professionals. Public health officials and healthcare leaders have used our findings to shape vaccine rollout strategies, protect essential workers, and reduce COVID-related risks in real-world settings.
In addition, the project has led to the publication of 10 peer-reviewed studies, which are already being cited by researchers and health agencies, showing that our work is contributing to both scientific knowledge and real-world decision-making.
Potential Influence
The research supported by my partnered award has strong potential to continue influencing vaccine policy, occupational health practices, and pandemic preparedness. As COVID-19 evolves and new variants emerge, the evidence we’ve generated on vaccine durability, booster timing, and immune response patterns will help shape ongoing vaccination strategies and booster recommendations for high-risk populations across Canada and internationally.
Beyond COVID-19, our research framework—particularly our approach to studying immune responses in real-world frontline settings—can serve as a model for evaluating vaccines in future outbreaks or public health emergencies. The methodologies and partnerships developed through this award also lay the foundation for new collaborative research that could expand into other areas of infectious disease control and immunization science. Ultimately, this work will continue to guide decision-makers in protecting essential workers, refining immunization schedules, and adapting public health interventions to emerging challenges.
Next Steps
I will be focusing on further research on Long COVID (post COVID condition) burden among paramedics in Canada. Will also try to compare the burden of Long COVID among several essential healthcare workers in Canada
Engagement in opioid agonist therapy and risk for repeat overdose in people living with and without HIV who experienced a nonfatal opioid overdose: Providing insight to improve clinical care
The ongoing drug toxicity and overdose (OD) crisis has ruined the lives of many people in British Columbia (BC). Opioid agonist therapy (OAT) reduces the risk for an OD, but not everyone who needs OAT has access to and is taking OAT. People living with HIV (PLWH) are disproportionately affected by the OD crisis and may be less likely to have access to OAT. This project aims to contribute to a strategy to connect people who visit an emergency department (ED) or a hospital due to a nonfatal opioid OD (NFOOD) with primary care and OAT. I will use routinely collected health data on all PLWH and a 10 percent random sample of the general population in BC, between 1992 and 2020. I will investigate — of everyone who visited an ED or a hospital after a NFOOD — who is most at risk of 1) not being connected to primary care and OAT, and 2) a repeated OD. I will compare people living with and without HIV. I also will have conversations with professionals from various backgrounds and individuals with lived and living experience. Through these, I hope to learn more about barriers to care. Based on what I learned, I will formulate recommendations on how to help people that experienced a NFOOD connect with care that best suits their needs, including OAT.
The relationship between the cortico-reticulospinal tract and motor function in stroke survivors
Stroke is a leading cause of long-term disability in Canada that causes movement impairments on one side of the body. In cases of severe movement impairment, there is often extensive damage to the primary descending motor pathway in the brain originating from the opposite side of the body. When this pathway is damaged, secondary motor pathways are altered which may support recovery in these individuals. Several of these secondary motor pathways originate from the same side of the brain as the impaired limb and are therefore undamaged in cases of stroke. My research aims to comprehensively investigate the role of the secondary motor pathways in motor function with chronic stroke survivors that have severe movement impairments. This research will use a combination of state-of-the-art brain stimulation and brain imaging techniques to gain novel insight into the relationship between the secondary motor pathways and the control of voluntary movement. My research will provide valuable insight into the role of the alternative motor pathways. In turn this information can be used in clinical practice to implement rehabilitation strategies that lead to better recovery and improved quality of life in individuals with severe strokes.
The role of Inflammatory bowel disease in the development of Alzheimer’s disease
People with inflammatory bowel disease (IBD) are six times as likely to develop Alzheimer’s disease and on average seven years sooner than people without IBD. IBD will affect 1 percent of Canadians in the next 10 years and there is no cure for this illness. IBD causes intestinal microbiome, neural, immune, and endocrine dysregulation, but the exact mechanisms that drive the development of Alzheimer’s and other dementias are unknown.
The goal of my research is to elucidate the mechanisms by which IBD increases the risk of Alzheimer’s and dementia with the long-term goal of developing pharmacological interventions.
The association of genetic risk factors with morphology and outcomes in interstitial lung disease
Interstitial lung disease (ILD) is a diverse group of illnesses with a variety of causes. The current approach to diagnosing ILD depends on the specific patterns observed on imaging studies (CT scan) and lung biopsy. There is increasing evidence that an individual’s genetics play a complex and important role in determining disease behaviour across different ILD subtypes. This study will examine whether common genetic risk factors predispose patients to different forms of ILD, influence treatment response, and predict prognosis. Investigating these genetic risk factors will improve our understanding of the biology that drives ILD and will help to develop a better system for ILD classification and diagnosis.
Risk and protective factors for cognitive health across the adult age span: Impacts of physical and mental health and illness on cognitive outcomes
The virus causing COVID-19 can invade the brain, raising concern over long-term impacts on thinking abilities. We aim to identify long-term impacts on these cognitive abilities in those who have had COVID-19, and pinpoint factors that predict long-term outcomes. Adults positive for COVID-19 and those with no evidence of infection, are completing a series of cognitive and psychological tests in a current study. The proposed project will follow these individuals over time, with one and three-year follow-ups to examine changes in cognition across time. We will examine group differences in cognition, mental health, and other factors at each time point, determine if one or more cognitive profiles (clusters) characterize COVID-19 positive individuals, examine changes in these profiles across time, and test a screening measure to detect these cognitive difficulties. Findings will inform clinicians (e.g. neurologists, rehabilitation specialists) on trajectory of recovery of function and inform healthcare service provision in BC. Results will help ensure long-term impacts of infection are appropriately addressed, so those affected can efficiently resume complex activities requiring cognitive effort (e.g. employment, academic pursuits).
Valvular heart disease and bioprosthetic heart valves: Defining mechanisms of degeneration and therapeutic discovery from bedside to bench
Aortic stenosis (AS) is a narrowing of the valve that controls blood flow from the heart to the body. AS results in significant decline in quality of life and can be fatal if untreated. Unlike most types of heart disease, there is no medication to treat AS and the primary therapy option is replacing the diseased valve with an artificial one by open-heart surgery or transcatheter implantation (insertion of an artificial valve through the blood vessels leading to the heart). Unfortunately, artificial valves can be dysfunctional and have limited durability, which can lead to heart failure, the need for repeat valve replacement, or death. With a focus on clot that can form on artificial valves, this research aims to determine the causes of valve dysfunction and degeneration, define methods to detect and predict which patients will experience valve dysfunction, and identify methods to increase valve durability. Overall, this work will provide critical new information to guide clinical care and the future evolution of artificial heart valve use that will improve the outcomes and quality of life of patients with AS.
Optimal pregnancy and postpartum health for everyone
After childbirth, mothers are at risk of death and disease. Patient engagement can improve the relevance and impact of research in this area; however, patient partners often do not reflect the diversity of the community. This limits the research and its results. This is especially important in BC, which is the most ethnically diverse province in Canada. The proposed research project aims to answer the following three questions: 1) How can we improve the diversity of patient partners in pregnancy and postpartum-related research? 2) Is a mobile application appropriate and acceptable for self-screening of postpartum complications? 3) What is the frequency, timing, and factors associated with postpartum complications and hospital readmissions in BC? The proposed research will promote equitable representation of pregnant and postpartum individuals in research, improving our understanding of their health and health concerns. It will be a core component of my portfolio of patient-oriented maternal health research in BC and globally.
Development of an ex-vivo-in-silico framework to inform medication use decisions for breastfeeding women
Children can inadvertently be exposed to the medications their mothers receive through breastmilk. As such, breastfeeding mothers need to weigh both the risks and benefits of medication use for themselves as well as their children. Unfortunately, the majority of drugs prescribed to breastfeeding women lack sufficient information to understand these risks. Due to this lack of information, women may opt to delay needed drug therapy or discontinue breastfeeding altogether — choices that can negatively impact the health of both mother and child. The proposed research program looks to address this information gap by combining lab-based studies with advanced computer modelling to predict how drug intake by the mother translates to drug exposure in the breastfed child. Lab-based studies will answer the question, “How much drug is present in breastmilk?” Whereas, advanced computing will be used to create virtual children and mothers to answer the question, “How much of the drug administered to the mother will be transferred to the breastfeeding child?” This will work ultimately serve to provide breastfeeding women and their caregivers with vital information to make the decisions regarding safe and effective drug therapy.