Weekly influenza surveillance overview, February 8, 2013 - Week 5

Surveillance report

The weekly/bi-weekly influenza surveillance overview is a collection of timely and relevant information regarding influenza activity in Europe. It provides key statistical data on a variety of issues including the following: sentinel surveillance of influenza-like illness and acute respiratory illness; virological surveillance; hospitalised laboratory-confirmed influenza cases; mortality surveillance and qualitative reporting. An up-to-date report is available on Fridays.

Executive summary

Influenza activity continued to increase across Europe, concludes the Weekly Influenza Surveillance Overview, Week 5, 2013. The epidemics may have passed their peaks in a few countries, although some countries experienced a resurgence of influenza-like-illness rates.

During week 5, 19 of the 29 countries reporting have indicated high/medium-intensity transmission and wide geographic spread. Twenty-two countries reported increasing trends in influenza activity.Virological survellance shows that the proportion of influenza-positive cases among sentinel specimens was high (55%), representing an increase from 52% on week 4/2013.

Since week 40/2012, the proportions of influenza A and B viruses have remained similar (51% vs. 49%), but among type A viruses, the percentage of A(H1)pdm09 has continued to increase (64%), compared to 52% in week 2/2012.