Grant: Op. Grant: Data Analysis Using Existing Databases and Cohorts-Infection/Immunity

Infectious diseases continue to pose a significant threat to children's health in Canada, despite the progress made through vaccinations. These infections still cause severe illnesses and account for about 10% of childhood deaths in the country. The Immunization Monitoring Program ACTive (IMPACT) is a network of 14 children's hospitals across Canada that has been monitoring diseases preventable by vaccines since 1991. Over the years, IMPACT has collected data on thousands of cases of diseases like sepsis, pneumonia, and meningitis. This data has been crucial in shaping vaccination policies at both national and provincial levels. This new research focuses on understanding the impact of these vaccine-preventable diseases (VPDs) on children in Canada who have weakened immune systems. The study will look at the number of cases, the age of affected children, and the outcomes, such as how often they needed intensive care or how long they stayed in the hospital. By comparing these findings with data from children with normal immune systems, the research aims to uncover the specific challenges faced by immunocompromised children. The study will also examine cases where vaccines did not fully protect children, despite them being up-to-date on their shots. The data used in this research will come from children treated in IMPACT hospitals between 1991 and 2024, covering a vast range of diseases. The results will help determine if current vaccination schedules need to be updated for children at high risk due to weakened immune systems. This comprehensive analysis will provide valuable insights into the health of immunocompromised children in Canada and may lead to better protection strategies for this vulnerable group.