Headlines - End of Influenza Surveillance for the 2013–2014 Season – Preliminary Report

The 2013-2014 season in France was characterized by a mild, short-lived influenza epidemic, dominated by equal circulation of the A(H1N1) pdm09 and A(H3N2) viruses in the community, with no particular severity. In Poitou-Charentes, the epidemic began in weeks 04 and 05 of 2014 with an increase in all surveillance indicators (unified network, hospital emergency departments, and SOS Médecins 17). The peak was reached in week 08 of 2014. At the peak, the incidence rate of consultations for influenza-like illness based on data from the unified network was 460/100,000 [95% confidence interval: 342–578], the number of consultations with SOS Médecins 17 reached 26, and the number of emergency department visits was 24, of which 2 resulted in hospitalization. The levels reached were significantly lower than in the previous 2012–2013 season. A decline in all indicators was observed in week 11 of 2014. Since the start of surveillance, 13 outbreaks of acute respiratory infections (ARI) in long-term care facilities for the elderly have been reported. Among the closed outbreaks (4), the median attack rates were 36% among residents and 0% among staff. Seven residents were hospitalized and 5 died. Among the facilities that responded, median influenza vaccination coverage was 95% among residents and 23% among staff. For 2 outbreaks, influenza was identified as the cause. During the winter of 2013–2014, surveillance of severe cases conducted by the InVS in the Poitou-Charentes region, in collaboration with intensive care units, identified 19 severe cases. All were adults, 7 (37%) of whom were aged 65 or older. Twelve (47%) severe cases had a risk factor for complications corresponding to a vaccination indication, including 3 obese individuals with no other comorbidities. One of the 18 cases for which information was available had been vaccinated. Eleven (58%) severe cases developed acute respiratory distress syndrome. Five deaths occurred. The A(H1N1)pdm09 virus was predominant (14 cases, or 74%), followed by the A(H3N2) virus (3 cases, or 16%). One case had an untyped influenza A virus, and information was not available for one case. The number of severe cases reported this winter is comparable to that of the previous flu season (21 cases).