Giuseppe
Emeritus
[Source: World Health Organization, full page: (LINK). Edited.]
Influenza Update N? 172, 9 November 2012
Summary
Countries in the temperate zone of the northern hemisphere
Many countries of the temperate regions of the Northern Hemisphere reported increasing numbers of detections of influenza, however, none have yet crossed their seasonal thresholds for ILI/ARI consultations rates and numbers of influenza virus detections are still low.
North America
In Canada, the national rate of influenza-like illness remained low however there has been a slight increase in the number of influenza virus detections. In addition, two influenza outbreaks were reported in long term care facilities and five influenza associated hospitalizations in persons over 65 years. influenza A accounted for 22 of 25 influenza viruses detection and all of the type A viruses with subtype information were influenza A(H3N2).
In the United States of America, ILI consultation rates are at 1.2%, below the seasonal threshold (2.2%). Many states are yet to report any influenza activity but 33 states have reported sporadic detections. Of 3036 specimens tested in late October, 188 (6.2%) were positive for influenza virus.
Among the positive influenza samples, 58% were influenza A and 97% of those were influenza A(H3N2).
Europe
Although overall influenza circulation remained low and below thresholds, there were, reports of increasing ILI activity in Armenia, Israel, Poland, the Republic of Moldova and western Russia.
Sporadic virus detections were reported in the Czech Republic, Denmark, France, Lithuania, Norway, regions of Russia, Sweden and United Kingdom.
Northern Asia
Northern China continued to report very low influenza activity, while in Mongolia, ILI activity has increased particularly in Dornod and Selenghe provinces. However, the large majority of viruses detected in Mongolia in October were respiratory viruses other than influenza.
Countries in the tropical zone
Tropical countries of the Americas
Influenza type B transmission has been noted in some countries of Central America and the Caribbean in recent weeks but is generally at low levels.
El Salvador, Costa Rica, and Nicaragua reported continued low level transmission of influenza type B, with smaller numbers of A(H3N2), following a peak of influenza B transmission in late August.
In the Caribbean, Jamaica has reported recent transmission of influenza B whilst in Cuba, numbers of influenza A(H1N1)pdm09 detections have increased slightly over several weeks following a peak influenza B transmission in June.
In the tropical zone of South America, influenza activity continues to decline with low numbers of virus detections being reported.
Influenza activity in Brazil appears overall to be decreasing with both influenza B and influenza A(H3N2) reported at low levels. Since the beginning of 2012, influenza viruses were detected in 21% (3900/18700) of SARI cases in Brazil. Of these, 66% (2588/3900) were influenza A(H1N1)pdm09.
Peru has reported low levels of mainly influenza B virus whilst in Paraguay, both influenza B and influenza A(H3N2) viruses have been reported.
(...)
Sub-Saharan Africa
Cameroon and Ethiopia have reported increasing transmission of influenza A(H3N2) since the last report. Kenya continued to report low circulation of mainly influenza B.
(...)
Tropical Asia
In tropical Asia, India, Sri Lanka, Cambodia and Nepal continued to report a mixture of influenza B and influenza A(H1N1)pdm09 circulation.
In India, influenza activity has decreased since peaking in mid-September. Influenza A(H1N1)pdm09 has been the most common virus detected throughout the season though it has been only slightly more common than influenza type B.
Sri Lanka and Thailand experienced a similar pattern of transmission, however, influenza A(H3N2) has become increasingly detected since early October in Sri Lanka.
Nepal is reporting increasing influenza activity, with mainly influenza B in circulation.
In southern China, influenza activity is at inter-seasonal levels, with some influenza A(H3N2) being reported.
In South East Asia, Cambodia, Lao PDR and Vietnam have all reported recent transmission of influenza virus but with differences in the most commonly detected type or subtype.
Cambodia has reported influenza A(H3N2) almost exclusively since early September, while Lao PDR has reported a mixture of influenza A(H1N1)pdm09 and influenza A(H3N2) and Vietnam a predominance of type B with lesser amounts of A(H3N2).
Countries in the temperate zone of the southern hemisphere
Influenza activity has continued to decline in all temperate countries of the southern hemisphere and is now at inter-seasonal levels.
Temperate countries of southern Africa
In South Africa, influenza activity is now at inter-seasonal levels, with only influenza B in circulation at very low levels. Zambia however, has reported sporadic cases of influenza A(H3N2) and influenza B viruses.
(...)
Oceania, Melanesia and Polynesia
Australia and New Zealand have finished their reporting for the influenza 2012 season.
Source of data
The Global Influenza Programme monitors influenza activity worldwide and publishes an update every two weeks.
The updates are based on available epidemiological and virological data sources, including FluNet (reported by the Global Influenza Surveillance and Response System) and influenza reports from WHO Regional Offices and Member States.
Completeness can vary among updates due to availability and quality of data available at the time when the update is developed.
Link to web pages
-
-------
Influenza Update N? 172, 9 November 2012
Summary
- Many countries of the Northern Hemisphere temperate region reported increasing detections of influenza viruses, particularly in North America and Western Europe, however none have crossed their seasonal threshold for ILI/ARI consultation rates.
- Several countries in the tropical areas experienced active transmission of influenza virus in recent weeks. In the Americas, Nicaragua and Costa Rica reported mainly influenza B virus detections. In Asia, India, Sri Lanka, Nepal, and Cambodia are all reporting a mixture of all three virus subtypes.
- In Sub-Saharan Africa, Cameroon and Ethiopia have reported an increase in influenza virus detections.
- Influenza activity in the temperate countries of the Southern Hemisphere is at inter-seasonal levels. A review of the 2012 southern hemisphere influenza season was published in the Weekly Epidemiological Record (WER) 2 November 2012, vol. 87, 44 (pp. 421?436)
Countries in the temperate zone of the northern hemisphere
Many countries of the temperate regions of the Northern Hemisphere reported increasing numbers of detections of influenza, however, none have yet crossed their seasonal thresholds for ILI/ARI consultations rates and numbers of influenza virus detections are still low.
North America
In Canada, the national rate of influenza-like illness remained low however there has been a slight increase in the number of influenza virus detections. In addition, two influenza outbreaks were reported in long term care facilities and five influenza associated hospitalizations in persons over 65 years. influenza A accounted for 22 of 25 influenza viruses detection and all of the type A viruses with subtype information were influenza A(H3N2).
In the United States of America, ILI consultation rates are at 1.2%, below the seasonal threshold (2.2%). Many states are yet to report any influenza activity but 33 states have reported sporadic detections. Of 3036 specimens tested in late October, 188 (6.2%) were positive for influenza virus.
Among the positive influenza samples, 58% were influenza A and 97% of those were influenza A(H3N2).
Europe
Although overall influenza circulation remained low and below thresholds, there were, reports of increasing ILI activity in Armenia, Israel, Poland, the Republic of Moldova and western Russia.
Sporadic virus detections were reported in the Czech Republic, Denmark, France, Lithuania, Norway, regions of Russia, Sweden and United Kingdom.
Northern Asia
Northern China continued to report very low influenza activity, while in Mongolia, ILI activity has increased particularly in Dornod and Selenghe provinces. However, the large majority of viruses detected in Mongolia in October were respiratory viruses other than influenza.
Countries in the tropical zone
Tropical countries of the Americas
Influenza type B transmission has been noted in some countries of Central America and the Caribbean in recent weeks but is generally at low levels.
El Salvador, Costa Rica, and Nicaragua reported continued low level transmission of influenza type B, with smaller numbers of A(H3N2), following a peak of influenza B transmission in late August.
In the Caribbean, Jamaica has reported recent transmission of influenza B whilst in Cuba, numbers of influenza A(H1N1)pdm09 detections have increased slightly over several weeks following a peak influenza B transmission in June.
In the tropical zone of South America, influenza activity continues to decline with low numbers of virus detections being reported.
Influenza activity in Brazil appears overall to be decreasing with both influenza B and influenza A(H3N2) reported at low levels. Since the beginning of 2012, influenza viruses were detected in 21% (3900/18700) of SARI cases in Brazil. Of these, 66% (2588/3900) were influenza A(H1N1)pdm09.
Peru has reported low levels of mainly influenza B virus whilst in Paraguay, both influenza B and influenza A(H3N2) viruses have been reported.
(...)
Sub-Saharan Africa
Cameroon and Ethiopia have reported increasing transmission of influenza A(H3N2) since the last report. Kenya continued to report low circulation of mainly influenza B.
(...)
Tropical Asia
In tropical Asia, India, Sri Lanka, Cambodia and Nepal continued to report a mixture of influenza B and influenza A(H1N1)pdm09 circulation.
In India, influenza activity has decreased since peaking in mid-September. Influenza A(H1N1)pdm09 has been the most common virus detected throughout the season though it has been only slightly more common than influenza type B.
Sri Lanka and Thailand experienced a similar pattern of transmission, however, influenza A(H3N2) has become increasingly detected since early October in Sri Lanka.
Nepal is reporting increasing influenza activity, with mainly influenza B in circulation.
In southern China, influenza activity is at inter-seasonal levels, with some influenza A(H3N2) being reported.
In South East Asia, Cambodia, Lao PDR and Vietnam have all reported recent transmission of influenza virus but with differences in the most commonly detected type or subtype.
Cambodia has reported influenza A(H3N2) almost exclusively since early September, while Lao PDR has reported a mixture of influenza A(H1N1)pdm09 and influenza A(H3N2) and Vietnam a predominance of type B with lesser amounts of A(H3N2).
Countries in the temperate zone of the southern hemisphere
Influenza activity has continued to decline in all temperate countries of the southern hemisphere and is now at inter-seasonal levels.
Temperate countries of southern Africa
In South Africa, influenza activity is now at inter-seasonal levels, with only influenza B in circulation at very low levels. Zambia however, has reported sporadic cases of influenza A(H3N2) and influenza B viruses.
(...)
Oceania, Melanesia and Polynesia
Australia and New Zealand have finished their reporting for the influenza 2012 season.
Source of data
The Global Influenza Programme monitors influenza activity worldwide and publishes an update every two weeks.
The updates are based on available epidemiological and virological data sources, including FluNet (reported by the Global Influenza Surveillance and Response System) and influenza reports from WHO Regional Offices and Member States.
Completeness can vary among updates due to availability and quality of data available at the time when the update is developed.
Link to web pages
- Epidemiological Influenza updates: http://www.who.int/influenza/surveillance_monitoring/updates/latest_update_GIP_surveillance
- Epidemiological Influenza updates archives 2012: http://www.who.int/influenza/surveillance_monitoring/updates/GIP_surveillance_2012_archives
- Virological surveillance updates : http://www.who.int/influenza/gisrs_laboratory/updates/summaryreport
- Virological surveillance updates archives : http://www.who.int/influenza/gisrs_laboratory/updates/en/index.html
-
-------