EISS Weekly Report: Week 46, 2005
The intensity of influenza activity in Europe remains low
Summary: Influenza activity in Europe remains at baseline levels. Sporadic laboratory confirmed cases of influenza were detected in the Czech Republic, Portugal, Scotland and Sweden in week 46/2005. Six influenza virus isolates were reported of which five were influenza A and one was influenza B. No human cases of influenza A(H5N1) virus have been reported in Europe. Laboratory reports of respiratory syncytial virus are increasing in various countries.
Epidemiological situation – week 46/2005: All countries reported a low intensity of influenza activity in week 46/2005. Two countries (Latvia, Lithuania) and three regions (England North, France North East and France South West) reported an increase in clinical activity compared to week 45/2005, but the incidence of influenza-like illness was low and at baseline levels.
For the geographical spread of influenza, France, Scotland and Switzerland reported sporadic influenza activity, which means that isolated cases of laboratory confirmed influenza infection have been detected. All other countries reported no influenza activity, meaning that the overall level of clinical activity remained at baseline levels and influenza virus infections are not being laboratory confirmed.
Definitions for the epidemiological indicators can be found here.
Virological situation - week 46/2005: The total number of respiratory specimens collected by sentinel physicians in week 46/2005 was 282, of which one was positive for influenza A virus in the Czech Republic. In addition, 1181 non-sentinel specimens (e.g. specimens collected in hospitals) were analysed and six tested positive for influenza virus: three influenza A(H3N2) in Sweden, two A unsubtyped in Scotland and one B in Portugal. Two countries reported dominant subtypes: influenza B in Switzerland and influenza A(H3N2) in Sweden.
Virological situation - 2005-2006 season (week 40-46/2005): Based on (sub)typing data of all influenza virus detections up to week 46/2005 (N=38; sentinel and non-sentinel data), 15 (39%) were influenza A (not subtyped), nine (24%) were A(H3) of which five were A(H3N2), one (3%) was A(H1N1) and 13 (34%) were influenza B. Based on the characterisation data of all influenza virus detections up to week 46/2005, six have been antigenically and/or genetically characterized: four A(H3) A/Califormia/7/2004 (H3N2)-like, one B/Shanghai/10/2003-like and one A/New Caledonia/20/99 (H1N1)-like. (click here).
Up to week 46/2005 no human cases of A(H5N1) influenza have been reported in Europe.
Comment: Influenza activity in Europe remains at baseline levels. Laboratory confirmed cases of influenza have been found sporadically throughout Europe so far this season: in the Czech Republic, England, Estonia, France, Poland, Portugal, Scotland, Slovenia, Sweden, Switzerland and Wales. As all the types and subtypes of influenza viruses that circulated last season have been detected (click here) it remains to be seen which virus will become dominant. While the influenza activity in Europe remains low, increases of respiratory syncytial virus (RSV) detections were reported by various countries (England, Estonia, France (click here), Ireland, Latvia, Luxembourg and Sweden).
Background: The Weekly Electronic Bulletin presents and comments influenza activity in 28 European countries. In week 46/2005, 24 countries reported clinical data and 23 countries reported virological data to EISS. The spread of influenza virus strains and their epidemiological impact in Europe is being carefully monitored by EISS in collaboration with the WHO Collaborating Centre in London, UK.
Other bulletins: To view national/regional bulletins in Europe and other bulletins from around the world, please click here. For a global update on the influenza A(H5N1) situation, please click here.
 | | | |
|
|
|
|
|
|
|
Map
The map presents the intensity of influenza activity and the geographical spread as assessed by each of the networks in EISS.
Clicking on the map will, if available, take you through to the national web site. If ´regional´ activity is reported, a pop-up text box will appear which describes the activity in greater detail.
Clicking on England and France will provide you with regional data.
A = Dominant virus A
H1N1 = Dominant virus A(H1N1)
H3N2 = Dominant virus A(H3N2)
H1N2 = Dominant virus A(H1N2)
B = Dominant virus B
A & B = Dominant virus A & B
= : stable clinical activity
+ : increasing clinical activity
- : decreasing clinical activity
|
|
Low = no influenza activity or influenza at baseline levels
Medium = usual levels of influenza activity
High = higher than usual levels of influenza activity
Very high = particularly severe levels of influenza activity
No activity = no evidence of influenza virus activity (clinical activity remains at baseline levels)
Sporadic = isolated cases of laboratory confirmed influenza infection
Local outbreak = increased influenza activity in local areas (e.g. a city) within a region,
or outbreaks in two or more institutions (e.g. schools) within a region. Laboratory confirmed.
Regional activity = influenza activity above baseline levels in one or more regions with
a population comprising less than 50% of the country´s total population. Laboratory confirmed.
Widespread = influenza activity above baseline levels in one or more regions with a population
comprising 50% or more of the country´s population. Laboratory confirmed.
| | |
|
|
|
|
|
|
|
|
|
|
|
Network comments (where available)
| |
France
First detection of influenza B on an hospitalised child in Ile de France region.
Italy
Milano and Parma Universities (Northern Italy) received the first samples of the new surveillance season, collected from patients with influenza-like illness. Analysis are in progress. One RSV virus was identified from a patient (7 months old) in Milano.
Slovenia
Sequencing of hemaglutinin gen of the imported A/H3N2 case that we reported in week 45 ranged the virus in the group of strains similar to A/Hong Kong/4355/05 that are probably still A/California/7/04-like. Sequencing was kindly provided by Dr. Olav Hungnes from the Norwegian Institute of Public Health. Occurrence of this imported case didn´t influenced the epidemiological situation of influenza like illness in Slovenia.
Sweden
Imported cases
Switzerland
2 influenza B viruses have been detected in the country : one in the Central part and one in the southern part of Switzerland. Samples have been detected during week 44 and 45.
| | |
|
|
|
|
|
|
|
|
|
|
|
Table and graphs (where available)
| |