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Influenza A(H3N2), A(H1N1)pdm09 and B viruses co-circulated in Europe in 2014/15. We undertook a multicentre case-control study in eight European countries to measure 2014/15 influenza vaccine effectiveness (VE) against medically-attended influenza-like illness (ILI) laboratory-confirmed as influenza. General practitioners swabbed all or a systematic sample of ILI patients. We compared the odds of vaccination of ILI influenza positive patients to negative patients. We calculated adjusted VE by influenza type/subtype, and age group. Among 6,579 ILI patients included, 1,828 were A(H3N2), 539 A(H1N1)pdm09 and 1,038 B. VE against A(H3N2) was 14.4% (95% confidence interval (CI): -6.3 to 31.0) overall, 20.7% (95%CI: -22.3 to 48.5), 10.9% (95%CI -30.8 to 39.3) and 15.8% (95% CI: -20.2 to 41.0) among those aged 0-14, 15-59 and  ?60??years, respectively. VE against A(H1N1)pdm09 was 54.2% (95%CI: 31.2 to 69.6) overall, 73.1% (95%CI: 39.6 to 88.1), 59.7% (95%CI: 10.9 to 81.8), and 22.4% (95%CI: -44.4 to 58.4) among those aged 0-14, 15-59 and  ?60?years respectively. VE against B was 48.0% (95%CI: 28.9 to 61.9) overall, 62.1% (95%CI: 14.9 to 83.1), 41.4% (95%CI: 6.2 to 63.4) and 50.4% (95%CI: 14.6 to 71.2) among those aged 0-14, 15-59 and ?60?years respectively. VE against A(H1N1)pdm09 and B was moderate. The low VE against A(H3N2) is consistent with the reported mismatch between circulating and vaccine strains. .


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  1. World Health Organization (WHO). Recommended composition of influenza virus vaccines for use in the 2014-2015 southern hemisphere influenza season [Internet]. WHO: Geneva; 2014 Sep. Available from: http://www.who.int/influenza/vaccines/virus/recommendations/201409_recommendation.pdf?ua=1
  2. National Institute for Medical Research. WHO Influenza Centre London. Report prepared for the WHO annual consultation on the composition of influenza vaccine for the Southern Hemisphere 2015. 22 – 24 September 2014. [Internet]. 2014. Available from: https://www.crick.ac.uk/media/221823/nimr-vcm-report-sep-14-web.pdf
  3. Centers for Disease Prevention and Control (CDC). CDC Health Advisory Regarding the Potential for Circulation of Drifted Influenza A (H3N2) Viruses. 2014 Dec 3; Available from: http://emergency.cdc.gov/HAN/han00374.asp
  4. Flannery B, Clippard J, Zimmerman RK, Nowalk MP, Jackson ML, Jackson LA, et al. Centers for Disease Control and Prevention. Early estimates of seasonal influenza vaccine effectiveness - United States, January 2015. MMWR Morb Mortal Wkly Rep. 2015;64(1):10-5. PMID: 25590680 
  5. Skowronski DM, Chambers C, Sabaiduc S, De Serres G, Dickinson JA, Winter AL, et al. Interim estimates of 2014/15 vaccine effectiveness against influenza A(H3N2) from Canada’s Sentinel Physician Surveillance Network, January 2015. Euro Surveill. 2015;20(4):21022.  https://doi.org/10.2807/1560-7917.ES2015.20.4.21022  PMID: 25655053 
  6. Pebody RG, Warburton F, Ellis J, Andrews N, Thompson C, von Wissmann B, et al. Low effectiveness of seasonal influenza vaccine in preventing laboratory-confirmed influenza in primary care in the United Kingdom: 2014/15 mid-season results. Euro Surveill. 2015;20(5):21025. . Available from: http://www.eurosurveillance.org/ViewArticle.aspx?ArticleId=21025 https://doi.org/10.2807/1560-7917.ES2015.20.5.21025  PMID: 25677050 
  7. Kissling E, Valenciano M, Buchholz U, Larrauri A, Cohen JM, Nunes B, et al. Influenza vaccine effectiveness estimates in Europe in a season with three influenza type/subtypes circulating: the I-MOVE multicentre case-control study, influenza season 2012/13. Euro Surveill. 2014;19(6):20701.  https://doi.org/10.2807/1560-7917.ES2014.19.6.20701  PMID: 24556348 
  8. Valenciano M, Kissling E, Reuss A, Jiménez-Jorge S, Horváth JK, Donnell JMO, et al. I-MOVE Multicentre Case Control Study Team. The European I-MOVE Multicentre 2013-2014 Case-Control Study. Homogeneous moderate influenza vaccine effectiveness against A(H1N1)pdm09 and heterogenous results by country against A(H3N2). Vaccine. 2015;33(24):2813-22.  https://doi.org/10.1016/j.vaccine.2015.04.012  PMID: 25936723 
  9. Kissling E, Valenciano M, Larrauri A, Oroszi B, Cohen JM, Nunes B, et al. Low and decreasing vaccine effectiveness against influenza A(H3) in 2011/12 among vaccination target groups in Europe: results from the I-MOVE multicentre case-control study. Euro Surveill. 2013;18(5):20390. PMID: 23399425 
  10. European Centre for Disease Prevention and Control (ECDC). Protocol for case control studies to measure pandemic and seasonal vaccine effectiveness in the European Union and European Economic Area [Internet]. Stockholm: ECDC; 2010. Available from: _http://www.ecdc.europa.eu/en/publications/Publications/0907_TED_Influenza_AH1N1_Measuring_Influenza_Vaccine_Effectiveness_Protocol_Case_Control_Studies.pdf_
  11. European Commission. Commission Decision 2009/363/EC of 30 April 2009 amending Decision 2002/253/EC laying down case definitions for reporting communicable diseases to the Community network under Decision No 2119/98/EC of the European Parliament and of the Council. [Internet]. 2009 Jan p. 58. Report No.: OJ L 110. Available from: http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2009:110:0058:0059:EN:PDF
  12. Huedo-Medina TB, Sanchez-Meca J, Marin-Martinez F, Botella J. Assessing heterogeneity in meta-analysis: Q statistic or I2 index? PsycholMethods. 2006 Jun;11(1082-989X (Print)):193-206.
  13. European Centre for Disease Prevention and Control. Influenza virus characterisation, summary Europe, June 2015 [Internet]. Stockholm: ECDC; 2015. Available from: http://ecdc.europa.eu/en/publications/Publications/influenza-virus-characterisation-June-2015.pdf
  14. Pebody R, Warburton F, Andrews N, Ellis J, von Wissmann B, Robertson C, et al. Effectiveness of seasonal influenza vaccine in preventing laboratory-confirmed influenza in primary care in the United Kingdom: 2014/15 end of season results. Euro Surveill. 2015;20(36):30013. . Available from: http://www.eurosurveillance.org/images/dynamic/EE/V20N36/art21237.pdf https://doi.org/10.2807/1560-7917.ES.2015.20.36.30013  PMID: 26535911 
  15. Ohmit SE, Petrie JG, Malosh RE, Cowling BJ, Thompson MG, Shay DK, et al. Influenza Vaccine Effectiveness in the Community and the Household. Clin Infect Dis [Internet]. 2013 May 15 [cited 2015 Aug 11];56(10):1363-9. Available from: http://cid.oxfordjournals.org/lookup/doi/10.1093/cid/cit060
  16. Pebody R, Andrews N, McMenamin J, Durnall H, Ellis J, Thompson CI, et al. Vaccine effectiveness of 2011/12 trivalent seasonal influenza vaccine in preventing laboratory-confirmed influenza in primary care in the United Kingdom: evidence of waning intra-seasonal protection. Euro Surveill. 2013;18(5):20389. PMID: 23399424 
  17. Skowronski DM, Janjua NZ, De Serres G, Sabaiduc S, Eshaghi A, Dickinson JA, et al. Low 2012-13 Influenza Vaccine Effectiveness Associated with Mutation in the Egg-Adapted H3N2 Vaccine Strain Not Antigenic Drift in Circulating Viruses. Kobinger GP, editor. PLoS ONE. 2014 Mar 25;9(3):e92153. Available from: http://dx.plos.org/10.1371/journal.pone.0092153
  18. Smith DJ. Mapping the Antigenic and Genetic Evolution of Influenza Virus. Science [Internet]. 2004 Jul 16 [cited 2013 May 14];305(5682):371-6. Available from: http://www.sciencemag.org/cgi/doi/10.1126/science.1097211
  19. European Medicine Agency. Explanatory note on the withdrawal of the Note for guidance on harmonisation of requirements for influenza Vaccines and of the core SmPC/PL for inactivated seasonal influenza vaccines. Jan 22, 2014.
  20. European Centre for Disease Prevention and Control (ECDC). Seasonal influenza vaccination in Europe- Overview of vaccination recommendations and coverage rates in the EU Member States for the 2012-13 influenza season. Stockholm: ECDC; 2015 Jan.
  21. Kaji M, Watanabe A, Aizawa H. Differences in clinical features between influenza A H1N1, A H3N2, and B in adult patients. Respirology. 2003;8(2):231-3. . Available from: http://doi.wiley.com/10.1046/j.1440-1843.2003.00457.x https://doi.org/10.1046/j.1440-1843.2003.00457.x  PMID: 12753540 
  22. Lee BE, Mukhi SN, Drews SJ. Association between patient age and influenza A subtype during influenza outbreaks. Infect Control Hosp Epidemiol. 2010;31(5):535-7. . Available from: http://www.jstor.org/stable/10.1086/652159 https://doi.org/10.1086/652159  PMID: 20334548 
  23. European Centre for Disease Prevention and Control (ECDC). Seasonal influenza vaccines. Stockholm: ECDC; 2016. Available from: http://ecdc.europa.eu/en/healthtopics/seasonal_influenza/vaccines/Pages/vaccines.aspx
  24. Simpson CR, Lone NI, Kavanagh K, Ritchie LD, Robertson C, Sheikh A, et al. Trivalent inactivated seasonal influenza vaccine effectiveness for the prevention of laboratory-confirmed influenza in a Scottish population 2000 to 2009. Euro Surveill. 2015;20(8):21043.  https://doi.org/10.2807/1560-7917.ES2015.20.8.21043  PMID: 25742433 
  25. Ohmit SE, Thompson MG, Petrie JG, Thaker SN, Jackson ML, Belongia EA, et al. Influenza vaccine effectiveness in the 2011-2012 season: protection against each circulating virus and the effect of prior vaccination on estimates. Clin Infect Dis. 2014;58(3):319-27.  https://doi.org/10.1093/cid/cit736  PMID: 24235265 
  26. McLean HQ, Thompson MG, Sundaram ME, Meece JK, McClure DL, Friedrich TC, et al. Impact of repeated vaccination on vaccine effectiveness against influenza A(G3N2) and B during 8 seasons. Clin Infect Dis. 2014 Nov 15;59(10):1375-85. doi: 10.1093/cid/ciu680. Epub 2014 Sep 29
  27. Sullivan SG, Kelly H. Stratified estimates of influenza vaccine effectiveness by prior vaccination: caution required. Clin Infect Dis. 2013;57(3):474-6.  https://doi.org/10.1093/cid/cit255  PMID: 23619811 

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