Association between the 2008-09 seasonal influenza vaccine and pandemic H1N1 illness during Spring-Summer 2009: four observational studies from Canada. oleh Danuta M Skowronski, Gaston De Serres, Natasha S Crowcroft, Naveed Z Janjua, Nicole Boulianne, Travis S Hottes, Laura C Rosella, James A Dickinson, Rodica Gilca, Pam Sethi, Najwa Ouhoummane, Donald J Willison, Isabelle Rouleau, Martin Petric, Kevin Fonseca, Steven J Drews, Anuradha Rebbapragada, Hugues Charest, Marie-Eve Hamelin, Guy Boivin, Jennifer L Gardy, Yan Li, Trijntje L Kwindt, David M Patrick, Robert C Brunham, Canadian SAVOIR Team