Ruiz PLD, et al. - This population-based registry study draws on data from the National Registry, the Norwegian Patient Registry, the Primary Care Database, the Norwegian Prescription Database and the Norwegian Surveillance System for Communicable Diseases to examine if pandemic and seasonal influenza infections are correlated with subsequent increased risk of type 1 diabetes. It was observed that the adjusted HR for type 1 diabetes after pandemic influenza infection was 1.19. No clear association was found between clinically reported pandemic influenza infection and incident type 1 diabetes, however a twofold increased risk of incident type 1 diabetes was seen in the subgroup with laboratory-confirmed pandemic influenza A.