Using Linked Laboratory and Health Administrative Data to Study Respiratory Syncytial Virus (RSV)-Associated Hospitalizations and Mortality in Adults in Ontario

Respiratory syncytial virus (RSV) is increasingly recognized as a serious illness in older adults and adults with certain comorbidities. As our population in Canada continues to age, both of these groups are of critical importance and understanding opportunities for healthy aging are paramount. RSV has been listed as a public health priority and there are several vaccines and antivirals currently in development, including those targeted for older adults, who are at high risk for RSV hospitalization, severe outcomes, and death. Given the changing landscape of RSV prevention, efforts need to focus on better understanding the epidemiology of RSV infections in this critical, pre-vaccine era, including disease burden in high-risk populations and factoring in consequences of severe RSV. We propose a series of studies of laboratory-confirmed severe RSV infections (i.e.,hospitalizations) in adults that will inform our understanding of disease burden and long-term impact of infection, and identify priority populations as vaccines are developed. We will estimate the burden of disease across Ontario in important subgroups, including by age group and comorbidity status, such as in immunocompromised adults. We will also examine risk factors for severe outcomes, such as admission to an intensive care unit, need for higher level of care following hospital discharge, and death. The results of these studies will help inform decision making as future vaccine strategies are evaluated and as antivirals become available and will build awareness about the impact of RSV infections in adults.