Weekly influenza surveillance overview, 5 – 11 Dec 2011 (week 49)
During week 49/2011, low influenza activity was notified by all 26 countries reporting.
Of 598 sentinel specimens tested, 12 (2.0%) were positive for influenza virus. Of the 67 influenza virus detections in sentinel specimens since week 40/2011, 51 were type A and 16 were type B viruses. Of 35 influenza A viruses found in sentinel specimens and subtyped, three were A(H1)pdm09 and 32 were A(H3) viruses.
Since week 40/2011, 78 SARI cases have been reported. Eighteen of them were confirmed influenza cases.
With no evidence of sustained transmission in EU/EEA countries at week 49, the annual influenza epidemics have yet to start this season in Europe.
Executive Summary
Europe is still reporting low influenza activity. ECDC has been monitoring the patterns of human influenza infection in the southern hemisphere countries in their winters as well as our own experience in Europe of last season as this gives some indication of what can be expected in the following northern hemisphere winter.
In a recent published article in Eurosurveillance, ECDC experts highlighted the diversity of experience in the 2011 influenza season (May to October) in the southern hemisphere. Though this was dominated by the A(H1N1) viruses that emerged during the 2009 influenza A(H1N1) pandemic and influenza B viruses, the proportion of these two varied between and within countries and influenza A(H3N2) viruses were also seen. It is important to note that the pattern of influenza in the southern hemisphere is only one of the many factors that the Centre takes into consideration in formulating its annual risk assessment in relation to severity and impact for epidemics of influenza.
During the influenza season citizens should adopt preventative measures recommended by their national authorities. These include personal hygiene measures and vaccination for those recommended. Vaccination is the single most effective way to prevent serious illness.
ECDC Director Marc Sprenger says: "Every year we know that many people, especially those in risk groups, will suffer as a consequence of influenza. ECDC takes its role in monitoring and providing scientific evidence on influenza very seriously in order to help countries and citizens prepare for the upcoming influenza season. However, even where we have experiences from other parts of the world to draw from we must also recognise that influenza is always unpredictable. Anticipating the precise nature of the European influenza season is difficult.
ECDC will continue to monitor activity in Europe in order to get the best picture of the emerging season but in the meantime I would like to stress that all Europeans who are recommended to have the influenza vaccine by their national authorities should get vaccinated as soon as possible. It is not too late to get vaccinated and it is of particular importance for those in the recognised risk groups and for healthcare workers".
