Abstract
ObjectiveDetailed data are lacking on influenza burden in the United Kingdom (UK). The objective of this study was to estimate the disease burden associated with influenza-like illness (ILI) in the United Kingdom stratified by age, risk and influenza vaccination status.MethodsThis retrospective, cross-sectional, exploratory, observational study used linked data from the General Practice Research Database and the Hospital Episode Statistics databases to estimate resource use and cost associated with ILI in the UK.ResultsData were included from 156,193 patients with ≥1 general practitioner visit with ILI. There were 21,518 high-risk patients, of whom 12,514 (58.2%) were vaccinated and 9,004 (41.8%) were not vaccinated, and 134,675 low-risk patients, of whom 17,482 (13.0%) were vaccinated and 117,193 (87.0%) were not vaccinated. High-risk vaccinated patients were older (p<0.001) and had more risk conditions (p<0.001). High-risk (odds ratio [OR] 2.16) or vaccinated (OR 1.19) patients had a higher probability of >1 general practitioner visit compared with low-risk and unvaccinated patients. Patients who were high-risk and vaccinated had a reduced risk of >1 general practitioner visit (OR 0.82; p<0.001). High-risk individuals who were also vaccinated had a lower probability of ILI-related hospitalisation than individuals who were high-risk or vaccinated alone (OR 0.59). In people aged ≥65 years, the mortality rate was lower in vaccinated than unvaccinated individuals (OR 0.75). The cost of ILI-related GP visits and hospital admissions in the UK over the study period in low-risk vaccinated patients was £27,391,142 and £141,932,471, respectively. In low-risk unvaccinated patients the corresponding values were £168,318,709 and £112,534,130, respectively.ConclusionsAlthough vaccination rates in target groups have increased, many people are still not receiving influenza vaccination, and the burden of ILI in the United Kingdom remains substantial. Improving influenza vaccination uptake may have the potential to reduce this burden.
Highlights
Influenza is an acute self-limiting viral disease which, in the majority of cases, is inconvenient but generally not serious
Influenza circulated from week 4 in 2001 according to surveillance data from the Health Protection Agency (HPA), so the study would have captured the majority of the influenza cases in the 2000–2001 season, it is possible that there were some cases in the last weeks of 2000 for which data were not collected
High-risk individuals who were vaccinated had a lower probability of influenza-like illness (ILI)-related hospitalisation than individuals who were high-risk or vaccinated alone (OR = 0.59; 95% CI 0.46 to 0.75; p
Summary
Influenza is an acute self-limiting viral disease which, in the majority of cases, is inconvenient but generally not serious. Seasonal influenza can cause severe illness, hospitalisations and deaths, especially in those who are at ‘high risk’ due to age or underlying chronic health problems. There are three types of influenza virus, Type A, Type B and Type C [1]; only A and B cause significant disease in humans [2]. Influenza A, of which there are currently two subtypes circulating, H1N1 and H3N2 [3], is responsible for seasonal epidemic and occasional pandemic activity. Annual vaccination against seasonal influenza is recommended for high-risk groups, including people aged 65 years or more and people with chronic health conditions [4], and the United Kingdom (UK) recently extended vaccination recommendations to include children [5,6]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
