Introduction
ADVERSE EVENTS, EVENTS, INFLUENZA
Vaccine safety surveillance is a core component of vaccination programs to monitor the safety of vaccines for health care professionals, policy makers, and the public. The implementation of a vaccine safety surveillance program increases the public confidence in various vaccines that are introduced [Vaccine pharmacovigilance in Canada currently involves passive and active surveillance systems that are designed to detect even very rare events in the population of vaccine recipients. However, passive surveillance suffers from underreporting and reporting biases (based on age, severity, and type of vaccine), while active surveillance occurs only for adverse events (AEs) in hospitalized children for specific conditions [Participant-centered active vaccine reporting offers a potentially more economical and sustainable mechanism to conduct large-scale pharmacovigilance as it allows for rapid identification of AEFIs with minimal human resource needs. The Canadian National Vaccine Safety (CANVAS) network was established in 2009 to provide enhanced monitoring for pandemic and seasonal influenza vaccines using rapid, web-based active surveillance. CANVAS provides timely influenza vaccine safety information annually, via a web-based survey, collected from over 50,000 adults and parents across Canada. CANVAS includes an unvaccinated control group, which provides a robust approach for conducting rapid evaluations of vaccine safety. The use of mobile health (mHealth) has allowed researchers, policy makers, and health care practitioners to reach individuals who are often less accessible, which, in turn, encompasses a broader and more representative sample of the population [mHealth is a rapidly growing field, and the near ubiquity of smartphones presents a unique opportunity to incorporate digital technologies to address public health issues, such as monitoring AEFIs, and facilitate communication between individuals and public health officials. With increased mobile device and app usage, the potential exists to capture, transmit, and monitor postimmunization experiences rapidly using self-reporting and personal mobile devices. For example, Australia has successfully implemented participant-centered digital AEFI reporting using SMS text messaging technology [In this study, we will evaluate the effectiveness and feasibility of using a mobile app for reporting participant-centered seasonal influenza AEFIs compared to a web-based notification platform.