Tweet
Weekly influenza surveillance overview - 10 December 2010 (ECDC, extract, edited): # The UK (England) also reported some severe cases, including several deaths, in young adults requiring intensive care.
Weekly influenza surveillance overview - 10 December 2010 (ECDC, extract, edited)
[Source: European Centre for Disease Prevention and Control (ECDC), full PDF document (LINK). Extract, edited.]
SURVEILLANCE REPORT
Weekly influenza surveillance overview - 10 December 2010
Main surveillance developments in week 48/2010 (29 Nov 2010 ? 05 Dec 2010)
This first page contains the main developments of this week and can be printed separately or together with the more detailed information following.
Sentinel surveillance of influenza-like illness (ILI)/ acute respiratory infection (ARI):
All reporting countries experienced influenza activity of low intensity. However, compared with the previous week, more countries reported sporadic activity and increasing trends. Local outbreaks were reported by three countries. Severe cases in young adults requiring intensive care, including some deaths, were reported in UK (England).
Virological surveillance:
In week 48/2010, an increasing percentage (10.1%) of sentinel specimens was positive for influenza compared with previous week. Of the 176 influenza viruses detected, 105 (60%) were type A and 71 (40%) were type B. Of the 52 sub-typed influenza A viruses, 48 (92.3%) were A(H1N1) 2009 and four (7.7%) were A(H3) virus.
Hospital surveillance of severe acute respiratory infection (SARI):
In addition to Romania?which has reported 43 SARI cases since week 37/2010?Slovakia has reported its first case and Belgium retroactively notified 227 cases for the current season.
Weekly analysis ? epidemiology
During week 48/2010, all 27 reporting countries experienced influenza activity of low intensity (Table 1, Map 1).
Sporadic activity was reported by 15 countries and the UK (Northern Ireland, Scotland and Wales) and local activity was reported by Norway and the UK (England). Nine countries reported no activity. (Table 1, Map 2).
The number of countries reporting a increasing trend for clinical activity increased from six in week 47/2010 to 11 in week 48/2010, including the UK (England and Wales) (Table 1, Map 2).
(...)
Table 1: Epidemiological and virological overview by country, week 48/2010
[Country - Intensity - Geographic spread - Trend - No. of sentinel swabs - Dominant type - Percentage positive* ILI per 100.000 - ARI per 100.000]
*Incidence per 100 000 is not calculated for these countries as no population denominator is provided.
Note: Liechtenstein is not reporting to the European Influenza Surveillance Network
Description of the system
This surveillance is based on nationally organized sentinel networks of physicians, mostly general practitioners (GPs), covering at least 1?5% of the population in their countries. All EU/EEA Member States (except Liechtenstein) are participating. Depending on their country?s choice, each sentinel physician reports the weekly number of patients seen with influenza-like illness (ILI), acute respiratory infection (ARI) or both to a national focal point. From the national level, both numerator and denominator data are then reported to the European Surveillance System (TESSy) database. Additional semi-quantitative indicators of intensity, geographic spread and trend of influenza activity at the national level are also reported.
Virological surveillance - Weekly analysis ? virology
In week 48/2010, 21 countries and the UK (England and Scotland) reported virological data.
Sentinel physicians collected 567 swabs with an increased percentage (10.1%) of specimens testing positive for influenza virus compared with last week. (Tables 1 and 2, Figure 3).
Belgium, Finland and the UK (England, Scotland) reported percentages for positive specimens between 19.4% and 31.3%.
In addition, 119 non-sentinel source specimens (i.e. specimens collected for diagnostic purpose in hospitals) were reported positive for influenza virus.
Of the 176 influenza viruses detected during week 48/2010, 105 (60%) were type A and 71 (40%) were type B.
Belgium, Italy, Norway, Portugal and the UK (England) reported influenza B viruses as the dominant type (Table 1).
Of the 52 influenza A viruses sub-typed, 48 (92.3%) were A(H1N1) 2009 and four (7.7%) were A(H3) (Table 2).
Since week 40/2010, of the 551 influenza detections in sentinel and non-sentinel specimens, 338 (61%) were influenza A and 213 (39%) were influenza B viruses. One hundred and ninety influenza A viruses have been sub-typed: 152 (80%) were 2009 pandemic A(H1N1) and 38 (20%) were A(H3) virus (Table 2).Trends of virological detections since week 40/2010 are shown in Figures 1?3.
Since week 40/2010, 55 influenza viruses from sentinel and non-sentinel specimens have been characterised antigenically (Table 3): 26 as A/California/7/2009 (H1N1)-like, eight as A/Perth/16/2009 (H3N2)-like, 20 as B/Brisbane/60/2008-like (Victoria lineage) and one as B/Florida/4/2006-like (Yamagata lineage).
More details on circulating viruses can be found in the report prepared by the Community Network of Reference Laboratories coordination team.
In week 48/2010, respiratory syncytial virus detections continued to increase for the ninth consecutive week (Figure 4).
Table 2: Weekly and cumulative influenza virus detections by type, subtype and surveillance system, weeks 40/2010?48/2010
[Virus Type/Subtype / Current Period: Sentinel - Non Sentinel / Season: Sentinel - Non Sentinel]
Note: A(pandemic H1), A(H3) and A(H1) includes both N-subtyped and not N-subtyped viruses
(...)
Table 3: Results of antigenic characterisations of sentinel and non-sentinel influenza virus isolates, weeks 40/2010?48/2010
[Strain name - Number of strains]
(...)
Country comments
Description of the system
According to the nationally defined sampling strategy, sentinel physicians take nasal or pharyngeal swabs from patients with influenza-like illness (ILI), acute respiratory infection (ARI) or both and send the specimens to influenza-specific reference laboratories for virus detection, (sub-)typing, antigenic or genetic characterisation and antiviral susceptibility testing.
For details on the current virus strains recommended by WHO for vaccine preparation click here.
Hospital surveillance ? severe acute respiratory infection (SARI) - Weekly analysis ? SARI
In addition to Romania, which has reported 43 SARI cases since week 37/2010, Slovakia has reported its first case.
Belgium retroactively notified 227 cases.
During week 48/2010, 33 SARI cases were reported: 24 in Belgium, eight in Romania and one in Slovakia. The gender ratio (male/female) was 1.5 and no information was available regarding the possible causative pathogens. Four cases were admitted to the intensive care unit and all cases needed respiratory support. The vaccination status of nine patients was known and eight of them were not vaccinated. Of the eight patients for whom information was available, three had no underlying conditions and four were infants less than two years old. No related fatalities were reported.
Table 4: Cumulative number of SARI cases, weeks 40/2010 - week 48/2010
[Country - Number of cases - Incidence of SARI cases per 100,000 population - Number of fatal cases reported - Incidence of fatal cases per 100,000 population - Estimated population covered]
(...)
Table 5: Number of SARI cases by age and gender, week 48/2010
[Age groups - Male - Female]
Table 6: Number of SARI cases by influenza type and subtype, week 48/2010
[Virus type/subtype - Number of cases during current week - Cumulative number of cases since the start of the season]
Table 7. Number of SARI cases by antiviral treatment, week 48/2010
[Antiviral treatment - Number of patients who received prophylaxis - Number of patients who received anti-viral treatment]
Table 8. Number of SARI cases by level of care and respiratory support, week 48/2010
[Respiratory support - ICU - Inpatient ward - Other - Unknown]
Table 9. Number of SARI cases by vaccination status, week 48/2010
[Vaccination Status - Number Of Cases - Percentage of cases]
Table 10. Number of underlying conditions in SARI cases by age group, week 48/2010
[Underlying condition/risk factor - Infant below 2 years - 2-17 years - 18-44 years - 45-59 years - >=60 years]
The report text was written by an editorial team at the European Centre for Disease Prevention and Control (ECDC): Eeva Broberg, Flaviu Plata, Phillip Zucs and Ren? Snacken. The bulletin text was reviewed by the Community Network of Reference Laboratories for Human Influenza in Europe (CNRL) coordination team: Adam Meijer, Rod Daniels, John McCauley and Maria Zambon. On behalf of the EISN members the bulletin text was reviewed by Bianca Snijders (RIVM Bilthoven, The Netherlands) and Thedi Ziegler (National Institute for Health and Welfare, Finland)
Maps and commentary used in this Weekly Influenza Surveillance Overview (WISO) do not imply any opinions whatsoever of ECDC or its partners on the legal status of the countries and territories shown or concerning their borders.
All data published in the WISO are up-to-date on the day of publication. Past this date, however, published data should not be used for longitudinal comparisons as countries tend to retrospectively update their numbers in the database.
? European Centre for Disease Prevention and Control, Stockholm, 2010
-
-----
[Source: European Centre for Disease Prevention and Control (ECDC), full PDF document (LINK). Extract, edited.]
SURVEILLANCE REPORT
Weekly influenza surveillance overview - 10 December 2010
Main surveillance developments in week 48/2010 (29 Nov 2010 ? 05 Dec 2010)
This first page contains the main developments of this week and can be printed separately or together with the more detailed information following.
- During week 48/2010, although all reporting countries experienced low intensity influenza activity, an increasing trend was notified by 11 countries including the UK (England). Finland, Norway and UK (England) reported local outbreaks.
- The UK (England) also reported some severe cases, including several deaths, in young adults requiring intensive care.
- An increasing percentage (10.1%) of positive influenza sentinel specimens was reported compared to last week.
- From positive sentinel and non-sentinel specimens, 60% were type A and 40% were type B.
- Of the 52 sub-typed influenza A viruses, 48 (92.3%) were A(H1N1) 2009 and four (7.7%) were A(H3).
- The influenza B virus was dominant in five countries.
- So far, circulating strains matched the vaccine strains.
- Thirty-three SARI cases were reported by three countries (Belgium, Romania and Slovakia). No cases were related to influenza infection.
Sentinel surveillance of influenza-like illness (ILI)/ acute respiratory infection (ARI):
All reporting countries experienced influenza activity of low intensity. However, compared with the previous week, more countries reported sporadic activity and increasing trends. Local outbreaks were reported by three countries. Severe cases in young adults requiring intensive care, including some deaths, were reported in UK (England).
Virological surveillance:
In week 48/2010, an increasing percentage (10.1%) of sentinel specimens was positive for influenza compared with previous week. Of the 176 influenza viruses detected, 105 (60%) were type A and 71 (40%) were type B. Of the 52 sub-typed influenza A viruses, 48 (92.3%) were A(H1N1) 2009 and four (7.7%) were A(H3) virus.
Hospital surveillance of severe acute respiratory infection (SARI):
In addition to Romania?which has reported 43 SARI cases since week 37/2010?Slovakia has reported its first case and Belgium retroactively notified 227 cases for the current season.
Weekly analysis ? epidemiology
During week 48/2010, all 27 reporting countries experienced influenza activity of low intensity (Table 1, Map 1).
Sporadic activity was reported by 15 countries and the UK (Northern Ireland, Scotland and Wales) and local activity was reported by Norway and the UK (England). Nine countries reported no activity. (Table 1, Map 2).
The number of countries reporting a increasing trend for clinical activity increased from six in week 47/2010 to 11 in week 48/2010, including the UK (England and Wales) (Table 1, Map 2).
(...)
Table 1: Epidemiological and virological overview by country, week 48/2010
[Country - Intensity - Geographic spread - Trend - No. of sentinel swabs - Dominant type - Percentage positive* ILI per 100.000 - ARI per 100.000]
- Austria - Low - No activity - Unknown (no information available) - 7 - None - 0.0 - ... - 30.2
- Belgium - Low - Sporadic - Stable - 19 - B - 26.3 - 34.2 - 854.3
- Bulgaria - Low - No activity - Stable - 40 - None - 0.0 - ... - 864.0
- Cyprus - Low - Sporadic - Stable - ... - ... - 0.0 - ...* - ...*
- Czech Republic - Low - Sporadic - Stable - ... - ... - 0.0 - 28.3 - 985.8
- Denmark - Low - No activity - Stable - 13 - None - 0.0 - 72.6 - ...
- Estonia - Low - Sporadic - Increasing - 16 - None - 6.3 - 5.7 - 340.6
- Finland - Low - Sporadic - Increasing - 31 - swoAH1N1 - 19.4 - ... - ...
- France - Low - Sporadic - Increasing - 50 - None - 4.0 - ... - 1765.9
- Germany - Low - No activity - Stable - 44 - None - 0.0 - ... - 1054.0
- Greece - Low - No activity - Stable - 3 - None - 0.0 - 61.8 - ...
- Hungary - Low - No activity - Increasing - ... - ... - 0.0 - 99.6 - ...
- Iceland - ... - ... - 0.0 - ... - ...
- Ireland - Low - No activity - Stable - 9 - None - 0.0 - 6.6 - ...
- Italy - ... - ... - ... - 17 - B - 5.9 - ... - ...
- Latvia - Low - Sporadic - Stable - 0 - None - 0.0 - 0.9 - 950.3
- Lithuania - Low - No activity - Increasing - ... - ... - 0.0 - 1.1 - 507.1
- Luxembourg - Low - Sporadic - Increasing - 10 - None - 10.0 - ...* - ...*
- Malta - Low - Sporadic - Stable - ... - ... - 0.0 - ...* - ...*
- Netherlands - Low - No activity - Stable - 10 - None - 10.0 - 33.5 - ...
- Norway - Low - Local - Increasing - 4 - B - 0.0 - 34.9 - ...
- Poland - Low - Sporadic - Increasing - 12 - None - 0.0 - 59.6 - ...
- Portugal - Low - Sporadic - Stable - 1 - B - 100.0 - 23.4 - ...
- Romania - Low - No activity - Decreasing - 44 - None - 0.0 - 15.6 - 721.9
- Slovakia - Low - Sporadic - Increasing - ... - 0.0 - 194.7 - 1719.1
- Slovenia - Low - Sporadic - Stable - 14 - None - 7.1 - 1.3 - 1041.1
- Spain - Low - Sporadic - Stable - 72 - swoAH1N1 - 11.1 - 22.6 - ...
- Sweden - Low - Sporadic - Increasing - 18 - B & swoAH1N1 - 5.6 - 3.6 - ...
- UK - England - Low - Local - Increasing - 109 - B - 22.0 - 13.3 - 492.5
- UK - Northern Ireland - Low - Sporadic - Stable - 8 - ... - 0.0 - 21.0 - 382.2
- UK - Scotland - Low - Sporadic - Decreasing - 16 - None - 31.3 - 4.3 - 222.7
- UK - Wales - Low - Sporadic - Increasing - ... - ... - 0.0 - 11.7 - ...
- Europe - ... - ... - ... - 567 - ... - 10.1 - ... - ...
*Incidence per 100 000 is not calculated for these countries as no population denominator is provided.
Note: Liechtenstein is not reporting to the European Influenza Surveillance Network
Description of the system
This surveillance is based on nationally organized sentinel networks of physicians, mostly general practitioners (GPs), covering at least 1?5% of the population in their countries. All EU/EEA Member States (except Liechtenstein) are participating. Depending on their country?s choice, each sentinel physician reports the weekly number of patients seen with influenza-like illness (ILI), acute respiratory infection (ARI) or both to a national focal point. From the national level, both numerator and denominator data are then reported to the European Surveillance System (TESSy) database. Additional semi-quantitative indicators of intensity, geographic spread and trend of influenza activity at the national level are also reported.
Virological surveillance - Weekly analysis ? virology
In week 48/2010, 21 countries and the UK (England and Scotland) reported virological data.
Sentinel physicians collected 567 swabs with an increased percentage (10.1%) of specimens testing positive for influenza virus compared with last week. (Tables 1 and 2, Figure 3).
Belgium, Finland and the UK (England, Scotland) reported percentages for positive specimens between 19.4% and 31.3%.
In addition, 119 non-sentinel source specimens (i.e. specimens collected for diagnostic purpose in hospitals) were reported positive for influenza virus.
Of the 176 influenza viruses detected during week 48/2010, 105 (60%) were type A and 71 (40%) were type B.
Belgium, Italy, Norway, Portugal and the UK (England) reported influenza B viruses as the dominant type (Table 1).
Of the 52 influenza A viruses sub-typed, 48 (92.3%) were A(H1N1) 2009 and four (7.7%) were A(H3) (Table 2).
Since week 40/2010, of the 551 influenza detections in sentinel and non-sentinel specimens, 338 (61%) were influenza A and 213 (39%) were influenza B viruses. One hundred and ninety influenza A viruses have been sub-typed: 152 (80%) were 2009 pandemic A(H1N1) and 38 (20%) were A(H3) virus (Table 2).Trends of virological detections since week 40/2010 are shown in Figures 1?3.
Since week 40/2010, 55 influenza viruses from sentinel and non-sentinel specimens have been characterised antigenically (Table 3): 26 as A/California/7/2009 (H1N1)-like, eight as A/Perth/16/2009 (H3N2)-like, 20 as B/Brisbane/60/2008-like (Victoria lineage) and one as B/Florida/4/2006-like (Yamagata lineage).
More details on circulating viruses can be found in the report prepared by the Community Network of Reference Laboratories coordination team.
In week 48/2010, respiratory syncytial virus detections continued to increase for the ninth consecutive week (Figure 4).
Table 2: Weekly and cumulative influenza virus detections by type, subtype and surveillance system, weeks 40/2010?48/2010
[Virus Type/Subtype / Current Period: Sentinel - Non Sentinel / Season: Sentinel - Non Sentinel]
- Influenza A / 34 - 71 / 113 - 225
- A (pandemic H1N1) / 31 - 17 / 88 - 64
- A (subtyping not performed) / 1 - 52 / 7 - 141
- A (not subtypable) / 0 - 0 / 0 - 0
- A (H3) / 2 -2 / 18 - 20
- A (H1) / 0 - 0 / 0 - 0
- Influenza B / 23 - 48 / 82 - 131
- Total Influenza / 57 - 119 / 195 - 356
Note: A(pandemic H1), A(H3) and A(H1) includes both N-subtyped and not N-subtyped viruses
(...)
Table 3: Results of antigenic characterisations of sentinel and non-sentinel influenza virus isolates, weeks 40/2010?48/2010
[Strain name - Number of strains]
- A(H1)v California/7/2009-like - 26
- A(H3) A/Brisbane/10/2007 (H3N2)-like - 0
- A(H3) A/Perth/16/2009 (H3N2)-like - 8
- B/Brisbane/60/2008-like (B/Victoria/2/87 lineage) - 20
- B/Florida/4/2006-like (B/Yamagata/16/88 lineage) - 1
(...)
Country comments
- Norway:
- Thirteen of the 17 influenza B detections in week 48 were from a single county in south-eastern Norway suggesting a local outbreak.
- Finland:
- Six 2009 pandemic A(H1N1) viruses were detected in one army training center.
- UK (England):
- Although general practitioner consultation rates remain low, several outbreaks and severe hospitalised cases have been reported indicating influenza transmission in the community.
- Several severe cases of influenza have been reported in the last two weeks resulting in an increase in ICU bed occupancy and in the provision of beds used for extracorporeal membrane oxygenation (ECMO) and some related deaths were reported.
- The majority of these patients are under 65 years of age.
- Further information can be found on the Health Protection Agency website.
Description of the system
According to the nationally defined sampling strategy, sentinel physicians take nasal or pharyngeal swabs from patients with influenza-like illness (ILI), acute respiratory infection (ARI) or both and send the specimens to influenza-specific reference laboratories for virus detection, (sub-)typing, antigenic or genetic characterisation and antiviral susceptibility testing.
For details on the current virus strains recommended by WHO for vaccine preparation click here.
Hospital surveillance ? severe acute respiratory infection (SARI) - Weekly analysis ? SARI
In addition to Romania, which has reported 43 SARI cases since week 37/2010, Slovakia has reported its first case.
Belgium retroactively notified 227 cases.
During week 48/2010, 33 SARI cases were reported: 24 in Belgium, eight in Romania and one in Slovakia. The gender ratio (male/female) was 1.5 and no information was available regarding the possible causative pathogens. Four cases were admitted to the intensive care unit and all cases needed respiratory support. The vaccination status of nine patients was known and eight of them were not vaccinated. Of the eight patients for whom information was available, three had no underlying conditions and four were infants less than two years old. No related fatalities were reported.
Table 4: Cumulative number of SARI cases, weeks 40/2010 - week 48/2010
[Country - Number of cases - Incidence of SARI cases per 100,000 population - Number of fatal cases reported - Incidence of fatal cases per 100,000 population - Estimated population covered]
- Belgium - 227 - ... - ... - ... - ...
- Romania - 43 - 0.67 - ... - ... - 6.413.821
- Slovakia - 1 - ... - ... - ... - ...
- Total - 271 - ... - ... - ... - ...
(...)
Table 5: Number of SARI cases by age and gender, week 48/2010
[Age groups - Male - Female]
- Under 2 - 13 - 6
- 2-17 - 5 - 4
- >=60 - 2 - 3
- Total - 20 - 13
Table 6: Number of SARI cases by influenza type and subtype, week 48/2010
[Virus type/subtype - Number of cases during current week - Cumulative number of cases since the start of the season]
- Influenza A - ... - ...
- A (pandemic H1N1) - ... - ...
- A(subtyping not performed) - ... - ...
- A(H3) - ... - ...
- A(H1) - ... - ...
- A(H5) - ... - ...
- Influenza B - ... - ...
- Unknown 33 - 268
- Total 33 - 268
Table 7. Number of SARI cases by antiviral treatment, week 48/2010
[Antiviral treatment - Number of patients who received prophylaxis - Number of patients who received anti-viral treatment]
- Oseltamivir - ... - 1
- Other (or combinations with other) - 1 - 1
- Unknown - 24 - 24
- None - 8 - 7
- Total - 33 - 33
Table 8. Number of SARI cases by level of care and respiratory support, week 48/2010
[Respiratory support - ICU - Inpatient ward - Other - Unknown]
- No respiratory support necessary - ... - 2 - ... - ...
- Oxygen therapy - 3 - 3 - ... - ...
- Respiratory support given unknown - 1 - ... - 24 - ...
Table 9. Number of SARI cases by vaccination status, week 48/2010
[Vaccination Status - Number Of Cases - Percentage of cases]
- Not full pandemic vaccination - 0 - 0
- Not vaccinated - 8 - 24
- Seasonal vaccination - 1 - 3
- Unknown - 24 - 73
- TOTAL - 33 - ...
Table 10. Number of underlying conditions in SARI cases by age group, week 48/2010
[Underlying condition/risk factor - Infant below 2 years - 2-17 years - 18-44 years - 45-59 years - >=60 years]
- Asthma - 1 - 1 - ... - ... - ...
- Chronic heart disease - ... - ... - ... - ... - 1
- Chronic lung disease - 1 - ... - ... - ... - ...
- Neuromuscular disorder - ... - ... - ... - ... - 1
- No underlying condition - 2 - ... - ... - ... - 1
- Other (please specify separately) - ... - 1 - ... - ... - ...
- Underlying condition unknown - 15 - 7 - ... - ... - 2
The report text was written by an editorial team at the European Centre for Disease Prevention and Control (ECDC): Eeva Broberg, Flaviu Plata, Phillip Zucs and Ren? Snacken. The bulletin text was reviewed by the Community Network of Reference Laboratories for Human Influenza in Europe (CNRL) coordination team: Adam Meijer, Rod Daniels, John McCauley and Maria Zambon. On behalf of the EISN members the bulletin text was reviewed by Bianca Snijders (RIVM Bilthoven, The Netherlands) and Thedi Ziegler (National Institute for Health and Welfare, Finland)
Maps and commentary used in this Weekly Influenza Surveillance Overview (WISO) do not imply any opinions whatsoever of ECDC or its partners on the legal status of the countries and territories shown or concerning their borders.
All data published in the WISO are up-to-date on the day of publication. Past this date, however, published data should not be used for longitudinal comparisons as countries tend to retrospectively update their numbers in the database.
? European Centre for Disease Prevention and Control, Stockholm, 2010
-
-----