What is Influenza?
Influenza Type A Virus
Other Influenza Virus Strains
Influenza is a seasonal disease in Europe, with a peak during the months from October to May. While most people recover quickly, regular seasonal epidemics in Europe cause severe illness and death [ECDC 2013]. The high prevalence of milder forms of the disease also contributes to a substantial social and economic burden, and pressure on health services [ECDC 2013].
Seasonal influenza particularly affects high-risk groups:
The 2010–11 influenza season in Europe was epidemiologically important as it was the first after the pandemic in 2009 and gave some indication of the characteristics of the new interpandemic (seasonal) influenza [ECDC 2013].
Data from France can provide indications of the burden of illness to the population [Institut de Veille Sanitaire 2013].
Hospitalisation [Who European Hospital Morbidity Database]
■ Hospitalisation rates peaked at 0.35 per 1000 during the pandemic year of 2009
■ The highest rates (0.87 and 1.55 per 1000) were recorded in Latvia and Lithuania, respectively
Mortality [Who Detailed European Mortality Database]
Use of reported influenza deaths to estimate influenza incidence provides comparable data over a number of countries. However, these reports probably underestimate deaths due to influenza and do not account for deaths occurring from a secondary infection (e.g. pneumonia) as a consequence of influenza.
Vaccination And Control Strategies
Vaccination of high risk and other groups can
reduce the clinical and economic burden of seasonal influenza; in the US the Centers for Disease Control and Prevention (CDC) recommends that all adults be vaccinated against seasonal influenza. In Europe, ECDC notes that there is a continuing need to [ECDC 2013]:
■ Increase influenza vaccine uptake
■ Improve surveillance for development of resistance to antiviral drugs
■ Recommend influenza immunisation to the population group aged over 65 years
Influenza: Summary Of Key Points