BACKGROUND: Results of previous influenza vaccination effects on current season influenza vaccine effectiveness (VE) are inconsistent. OBJECTIVES: To explore previous influenza vaccination effects on current season VE among population targeted for vaccination. METHODS: We used 2011/2012 to 2016/2017 I-MOVE primary care multicentre test-negative data. For each season, we compared current season adjusted VE (aVE)...
Since the 2008/9 influenza season, the I-MOVE multicentre case-control study measures influenza vaccine effectiveness (VE) against medically-attended influenza-like-illness (ILI) laboratory confirmed as influenza. In 2011/12, European studies reported a decline in VE against influenza A(H3N2) within the season. Using combined I-MOVE data from 2010/11 to 2014/15 we studied the effects of time since vaccination o...