Clinical presentation of influenza patients according to age group and influenza virus type and subtype in the age groups 15–64 years and 65 years or older.

(a) These include all influenza cases, including those that were not subtyped/characterized.(b) sudden onset of symptoms is not presented as included in the ARI case definition; dyspnoea is not presented as only collected since the 2009–2010 season; myalgia and cephalalgia were not considered among children aged 0–4 years as they cannot report their subjective symptoms.p-value for the comparison with influenza B patients of the same age group:* **Univariate analysis. The IBVD (Influenza B in Vircases database) study, France, 2003–2004 to 2012–2013.