The Canadian National Vaccine Safety Network: surveillance of adverse events following immunisation among individuals immunised with the COVID-19 vaccine, a cohort study in Canada

IntroductionCOVID-19 vaccines require enhanced safety monitoring after emergency approval. The Canadian National Vaccine Safety Network monitors the safety of COVID-19 vaccines and provides enhanced monitoring for healthy, auto-immune, immunocompromised, pregnant and breastfeeding populations and allows for the detection of safety signals.Methods and analysisOnline participant reporting of health events in vaccinated and unvaccinated individuals 12 years of age and older is captured in three surveys: 1 week after dose 1, 1 week after dose 2 and 7 months after dose 1. Medically attended events are followed up by telephone. The number, percentage, rate per 10 000 and incident rate ratios with 95% CIs are calculated by health event, vaccine type, sex and in 10-year age groups.Ethics and disseminationEach study site has Research Ethics Board approvals for the project (UBC Children’s & Women’s, CIUSSS de l'Estrie—CHUS, Health PEI, Conjoint Health Research Ethics Board, University of Calgary and Alberta Health Services, IWK Health, Unity Health Toronto and CHU de Québec-Université Laval Research Ethics Boards). Individuals are invited to participate in this active surveillance and electronic consent is given before proceeding to each survey. Weekly reports are shared with public health and posted on the study website. At least one peer-reviewed manuscript is produced.