# 5250
While the UK was hit hard relatively early this winter by a return of the swine flu and influenza B viruses, much of the rest of Europe has so far been spared serious outbreaks of flu.
In many of the countries reporting widespread influenza activity, the impact and intensity of this year’s flu season has thus far been low or moderate.
Geographical Spread of Influenza – Week 2
But of course, there remains several more months of potential flu season ahead, and so even slow increases in activity are worthy of our attention.
Continued slow increase in influenza activity across Europe
This issue is based on data reported in week 2/2011 by 46 Member States in the WHO European Region. Influenza activity has progressed across the Region following a west-to-east trend. 44% of sentinel specimens were positive for influenza. Pandemic influenza A(H1N1) 2009 remains the dominant virus, particularly in the western part of the Region. Countries continue to report cases of severe disease caused mainly by pandemic influenza A(H1N1) 2009 virus infections (see network comments).
Current situation - week 02/2011
Of the 38 countries reporting on consultation rates for influenza-like illness (ILI) and acute respiratory infection (ARI), 20 reported increases while 2 reported decreases. In the remaining 16 countries, consultation rates were largely unchanged.In general, the highest consultation rates were reported for children aged 0-14 years. Information on the intensity of influenza activity was available for 40 countries. Most countries reported medium (24) or low (13) activity, while 1 (Luxembourg) reported very high influenza activity and 2 others (Ireland and Norway) reported high activity.
Influenza was reported to be widespread in 15 countries, regional in 7 countries and local in 7 countries; 11 countries reported no or sporadic activity. Influenza levels were highest in the western part of the Region. Of the 23 countries reporting on the impact of influenza on health care systems, 19 described it as low overall. Ireland reported severe impact on its health care capacity, while 3 other countries (Estonia, Georgia and Israel) reported moderate impact.
Interestingly, the virological components of this year’s flu season in Europe is completely opposite of what we’ve seen in North America, where the H3N2 influenza A virus has been dominant.
A listing of the cumulative virological sampling to date (week 40/2010 – week 2/2011) show, that of 22,479 positive tests:
16,055 (71%) were influenza A, of which 9866 were subtyped.
- Of those, 9,327 (95%) as pandemic influenza A(H1)
- 537 (5%) as influenza A(H3)
- And, surprisingly, 2 (less than 1%) were identified as the old seasonal A(H1) virus.
The continued (extremely) low level detection of the old seasonal H1N1 virus is an interesting anomaly. Right now it is impossible to know if these are simply the last gasps of a dying strain, or are tiny viral embers that could once again billow.
While a return of the old H1N1 at this time seems highly doubtful - given the unpredictability of influenza - one should never bet the farm saying it couldn’t happen.
