Serial Vaccination and the Antigenic Distance Hypothesis: Effects on Influenza Vaccine Effectiveness During A(H3N2) Epidemics in Canada, 2010–2011 to 2014–2015

摘要: Background The antigenic distance hypothesis (ADH) predicts that negative interference from prior season's influenza vaccine (v1) on the current (v2) protection may occur when is small between v1 and v2 (v1 ≈ v2) but large epidemic (e) strain ≠ e). Methods Vaccine effectiveness (VE) against medically attended, laboratory-confirmed A(H3N2) illness was estimated by test-negative design during 3 epidemics (2010-2011, 2012-2013, 2014-2015) in Canada. derived with covariate adjustment across and/or categories relative to no receipt among outpatients aged ≥9 years. Prior vaccination effects were interpreted within ADH framework. Results varied significantly season, consistent ADH. There 2010-2011 e, comparable VE for alone or + v1: 34% (95% confidence interval [CI] = -51% 71%) versus CI -5% 58%). Negative suggested 2012-2013 nonsignificant reduction e: 49% -47% 83%) 28% -12% 54%). of pronounced statistically significant 2014-2015 ≡ 65% 25% -33% -78% 1%). Conclusions Effects repeat have contributed findings low recent since 2010