Reducing the impact of imported infections in Ontario

Public health must remain responsive to the population’s changing health needs. As Canada’s diversity grows through immigration, protecting the health of immigrants when they travel to visit friends and relatives (VFR) is one such need. Immigrants comprise a growing proportion of international travelers and experience disproportionate travel-related infectious disease morbidity and mortality. While many infections are preventable, few immigrant travelers access pre-travel health services, in part because they are not covered under provincial health insurance plans. In my dissertation, I present three studies designed to respond to current gaps in evidence regarding how immigrant travelers perceive and respond to travel health risks, and how to measure travel-related disease burden. In the first study, I use qualitative methods to explore how South Asian travelers in Peel region conceptualize travel health risks. I found that travelers face many health challenges when traveling but adjust their behaviours to avoid or minimize key risks where possible. Their responses to risks, however, can be constrained by competing concerns (e.g. rushed travel, wanting to avoid family conflicts, cost, and a desire to enjoy traditional cuisine). These results highlight the importance of the social context in which travelers make health decisions. In the second study, I use novel data linkages to evaluate the utility of health administrative data for identifying hepatitis A, malaria and enteric fever infections. While diagnostic codes were sensitive, and additionally identified individuals who were likely unreported to public health, I found that their predictive value for accurately identifying cases was low. These results caution against the use of health administrative data, on its own, for this purpose. In the third study, I use a matched cohort design to estimate the health care utilization and attributable cost of hepatitis A, malaria and enteric fever infections in Peel region. Over three years, 318 cases resulted in more than $2 million dollars in direct health care spending, and attributable medical costs ranged from $4,500 - $8,000 per case. These results highlight that travel-related infections require substantial resources for diagnosis and treatment as most medically-attended cases require inpatient health care. Together, results from this dissertation advance our understanding of the complex social settings in which immigrant travelers make health-related decisions, and identify how much these avoidable infections cost Ontario’s health care system. Findings point to concrete opportunities to reduce disease burden through tailored health promotion strategies that are sensitive to the unique challenges immigrant travelers face. Costing estimates provide necessary model parameters to explore the cost-effectiveness of policies designed to improve access to pre-travel health services for high risk travelers.Ph.D.2019-07-11 00:00:0