Influenza Burden Assessment in the United Kingdom, 1996-2008

Study Overview
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Brief Summary
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The study will assess the burden of influenza by age, risk status, vaccination status and influenza subtype, in order to create a complete profile of the burden of influenza-related morbidity and mortality in United Kingdom from 1996 to 2008.

Detailed Description
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This epidemiological study is a modelling of time series retrospectively extracted from multiple databases. The data collection will be a query of existing electronic healthcare databases.

Official Title
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Burden of Influenza in the United Kingdom, 1996-2008

Conditions
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Influenza

Intervention / Treatment
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* Other: Data collection


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: • Registration with an acceptable flag in the GPRD, or registration with a potentially influenza-related event in the HES database or the ONS mortality data. Exclusion Criteria: -
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Cohort Group<br> | Other: Data collection<br>* The study, will use four primary data sources: the General Practice Research Database (GPRD, for mild outcomes), the Hospital Episode Statistics database (HES, for hospitalizations), the Office of National Statistics mortality database (ONS, for mortality), and weekly virology data from the Health Protection Agency (HPA). Weekly time series of the rates of various influenza-related health outcomes in the various databases, such as office visits for acute otitis media and hospitalizations for pneumonia will be constructed. Statistical models, guided by weekly numbers of cases of laboratory-confirmed influenza and respiratory syncytial virus (RSV) contained in the HPA virology data, to estimate the portions of the various outcomes that can be attributed to influenza will be constructed. Finally, the seasonal impact of influenza by risk status, vaccination status, and seasons in which a well-matched versus mismatched influenza vaccine was used, will be assessed.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of medically attended health outcomes ( 20 relevant mild and severe) related to influenza |  | From 1996 to 2008 (up to 13 years) | 
| Relative impact of influenza on high versus low risk populations |  | From 1996 to 2008 (up yo 13 years) | 
| Relative impact of influenza during match versus mismatched seasons |  | From 1996 to 2008 (up to 13 years) | 
| Relative impact of influenza on vaccinated versus unvaccinated populations |  | From 1996 to 2008 (up to 13 years) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Office of National Statistics, Burden of Disease, Influenza, Hospital Episode Statistics, General Practitioners Research Database