Key Points

Influenza surveillance in Languedoc-Roussillon has been strengthened since the 2009–10 H1N1 pandemic. Several measures are in place to provide regional descriptive, alert, and impact data. The Cire monitors the winter epidemic and issues a weekly report. The 2013–14 season was marked by a low-intensity, short-lived national influenza epidemic, dominated by the circulation of the A(H1N1)pdm09 and A(H3N2) viruses in equal proportions in the community, with no particular severity. Due to the low circulation of the B virus, the overall scale of the epidemic was smaller than in previous years: 1,362,770 cases of influenza in primary care over 6 epidemic weeks, according to the national estimate by the Sentinelles network. In Languedoc-Roussillon, a similar epidemic profile was observed, with low intensity (fewer than 700 cases per 10⁵ inhabitants at the epidemic peak, compared to more than 900 in previous years) and a relatively short duration (6 weeks compared to 13 the previous year). Only the A (H1N1)pdm09 virus was identified in regional samples; this may be explained by the fact that few samples are analyzed using molecular biology methods and that they are exclusively of hospital origin (greater severity of this virus compared to H3N2).Thirty-six severe cases of influenza, mostly among unvaccinated individuals, were reported by intensive care physicians.