Eleftheria Vasileiou1, Aziz Sheikh1, Chris C Butler2, Chris Robertson3, Kimberley Kavanagh4, Tanya Englishby4, Nazir I Lone1, Beatrix von Wissmann5, Jim McMenamin5, Lewis D Ritchie6, Jürgen Schwarze7, Rory Gunson8, Colin R Simpson1,9. 1. Asthma UK Centre for Applied Research, Usher Institute, The University of Edinburgh, Edinburgh, United Kingdom. 2. Nuffield Department of Primary Care Health Sciences, Oxford University, New Radcliffe House, Radcliffe Observatory Quarter, Oxford, United Kingdom and Cardiff University, Institute of Primary Care and Public Health, Cardiff, United Kingdom. 3. Department of Mathematics and Statistics, University of Strathclyde, Glasgow, United Kingdom and Health Protection Scotland, Glasgow, United Kingdom. 4. Department of Mathematics and Statistics, University of Strathclyde, Glasgow, United Kingdom. 5. Health Protection Scotland, National Health Service (NHS) National Services Scotland, Glasgow, United Kingdom. 6. Centre of Academic Primary Care, University of Aberdeen, Aberdeen, United Kingdom. 7. Centre for Inflammation Research, Queen's Medical Research Institute, Child Life and Health, The University of Edinburgh, Edinburgh, United Kingdom. 8. West of Scotland Specialist Virology Centre, Glasgow, United Kingdom. 9. School of Health, Faculty of Health, Victoria University of Wellington, Wellington, New Zealand and Asthma UK Centre for Applied Research, Usher Institute, The University of Edinburgh, Edinburgh, United Kingdom.
Abstract
BACKGROUND: Influenza infection is a trigger of asthma attacks. Influenza vaccination can potentially reduce the incidence of influenza in people with asthma, but uptake remains persistently low, partially reflecting concerns about vaccine effectiveness (VE). METHODS: We conducted a test-negative designed case-control study to estimate the effectiveness of influenza vaccine in people with asthma in Scotland over 6 seasons (2010/2011 to 2015/2016). We used individual patient-level data from 223 practices, which yielded 1 830 772 patient-years of data that were linked with virological (n = 5910 swabs) data. RESULTS: Vaccination was associated with an overall 55.0% (95% confidence interval [CI], 45.8-62.7) risk reduction of laboratory-confirmed influenza infections in people with asthma over 6 seasons. There were substantial variations in VE between seasons, influenza strains, and age groups. The highest VE (76.1%; 95% CI, 55.6-87.1) was found in the 2010/2011 season, when the A(H1N1) strain dominated and there was a good antigenic vaccine match. High protection was observed against the A(H1N1) (eg, 2010/2011; 70.7%; 95% CI, 32.5-87.3) and B strains (eg, 2010/2011; 83.2%; 95% CI, 44.3-94.9), but there was lower protection for the A(H3N2) strain (eg, 2014/2015; 26.4%; 95% CI, -12.0 to 51.6). The highest VE against all viral strains was observed in adults aged 18-54 years (57.0%; 95% CI, 42.3-68.0). CONCLUSIONS: Influenza vaccination gave meaningful protection against laboratory-confirmed influenza in people with asthma across all seasons. Strategies to boost influenza vaccine uptake have the potential to substantially reduce influenza-triggered asthma attacks.
BACKGROUND:Influenza infection is a trigger of asthma attacks. Influenza vaccination can potentially reduce the incidence of influenza in people with asthma, but uptake remains persistently low, partially reflecting concerns about vaccine effectiveness (VE). METHODS: We conducted a test-negative designed case-control study to estimate the effectiveness of influenza vaccine in people with asthma in Scotland over 6 seasons (2010/2011 to 2015/2016). We used individual patient-level data from 223 practices, which yielded 1 830 772 patient-years of data that were linked with virological (n = 5910 swabs) data. RESULTS: Vaccination was associated with an overall 55.0% (95% confidence interval [CI], 45.8-62.7) risk reduction of laboratory-confirmed influenza infections in people with asthma over 6 seasons. There were substantial variations in VE between seasons, influenza strains, and age groups. The highest VE (76.1%; 95% CI, 55.6-87.1) was found in the 2010/2011 season, when the A(H1N1) strain dominated and there was a good antigenic vaccine match. High protection was observed against the A(H1N1) (eg, 2010/2011; 70.7%; 95% CI, 32.5-87.3) and B strains (eg, 2010/2011; 83.2%; 95% CI, 44.3-94.9), but there was lower protection for the A(H3N2) strain (eg, 2014/2015; 26.4%; 95% CI, -12.0 to 51.6). The highest VE against all viral strains was observed in adults aged 18-54 years (57.0%; 95% CI, 42.3-68.0). CONCLUSIONS: Influenza vaccination gave meaningful protection against laboratory-confirmed influenza in people with asthma across all seasons. Strategies to boost influenza vaccine uptake have the potential to substantially reduce influenza-triggered asthma attacks.
Authors: Matt D T Hitchings; Joseph A Lewnard; Natalie E Dean; Albert I Ko; Otavio T Ranzani; Jason R Andrews; Derek A T Cummings Journal: Epidemiology Date: 2022-04-01 Impact factor: 4.860
Authors: Sarah J Stock; Jade Carruthers; Cheryl Denny; Jack Donaghy; Anna Goulding; Lisa E M Hopcroft; Leanne Hopkins; Rachel Mulholland; Utkarsh Agrawal; Bonnie Auyeung; Srinivasa Vittal Katikireddi; Colin McCowan; Josie Murray; Chris Robertson; Aziz Sheikh; Ting Shi; Colin R Simpson; Eleftheria Vasileiou; Rachael Wood Journal: Int J Epidemiol Date: 2022-10-13 Impact factor: 9.685