Highlight: Severe influenza cases admitted to intensive care: start of the 2013–14 winter surveillance

Surveillance of severe influenza cases during the 2011-12 flu season identified 823 severe cases in France, including 7 in Midi-Pyrénées (1%), thanks to the participation of intensive care units. The number of severe influenza cases recorded last winter was higher than in the two previous seasons (326 in the winter of 2011-12, including 7 in Midi-Pyrénées, and 780 in the winter of 2010-11, including 21 in Midi-Pyrénées) but lower than during the 2009-2010 pandemic, during which 1,305 cases of influenza were recorded in intensive care units (including 42 in Midi-Pyrénées). Severe influenza cases admitted to intensive care in 2012–13 were predominantly linked to a type A virus (68%), of which 67% were due to the A(H1N1)pdm09 virus. The case fatality rate was comparable to that observed in previous years (19% in 2012–13). The community influenza epidemic was marked by a particularly long duration (13 weeks) with the concurrent circulation of all three influenza viruses. It therefore seems important for the InVS to continue surveillance of severe influenza cases in intensive care (adult and pediatric) for the 2013–14 season. This surveillance began in the first week of November (week 45) using the same procedures as last year (report forms to be returned by intensive care physicians to the Midi-Pyrénées Regional Health Agency). The main objectives of this system are: - To track the weekly number of severe cases to measure the impact of the epidemic; - To describe the epidemiological characteristics of severe cases in order to adapt control measures as necessary; - To assess the effectiveness of this season’s vaccine against severe forms of influenza.We would like to thank in advance the partners involved in this surveillance: the laboratories at the Toulouse University Hospital (virology) and the Cahors Hospital, as well as the intensive care units in Midi-Pyrénées (CHIVA, Rodez Hospital, Millau Hospital, Toulouse University Hospital, Pasteur Clinic, Union Clinic, Parc Polyclinic, Occitanie Clinic, Clinique des Cèdres, St-Gaudens Hospital, Auch Hospital, Cahors Hospital, Tarbes Hospital, Lourdes Hospital, Albi Hospital, Claude Bernard Hospital, Castres-Mazamet Hospital, Montauban Hospital, and Clinique Pont de Chaume).