Effectiveness of pandemic and seasonal influenza vaccines in preventing laboratory-confirmed influenza in Adults: A clinical cohort study during epidemic seasons 2009-2010 and 2010-2011 in Finland

Abstract

Background: One dose of pandemic influenza vaccine Pandemrix (GlaxoSmithKline) was offered to the entire population of Finland in 2009-10. We conducted a prospective clinical cohort study to determine the vaccine effectiveness in preventing febrile laboratory-confirmed influenza infection during the influenza season 2009-10 and continued the study in 2010-11./absp.