25 January 2016, - Update number 255, based on data up to 17 January, 2015
High levels of influenza activity continued in some countries in western Asia. And increasing influenza activity was reported in northern America, northern and eastern Europe and northern/temperate Asia. Most detected influenza viruses were influenza A(H1N1)pdm09.
- Influenza activity was slowly increasing but still below seasonal expected levels in northern America. In northern and eastern Europe increasing influenza activity was reported, with still low activity in Western and Southern Europe. An increase in severe acute respiratory infections due to influenza A(H1N1)pdm09 was reported from some eastern European countries.
- In northern/temperate Asia, influenza activity was ongoing in Mongolia and was increasing in the Republic of Korea.
- In central and western Asia, influenza activity remained at high levels where Israel, Jordan and Oman reported increased influenza activity, predominantly due to influenza A(H1N1)pdm09 and influenza B viruses. Pakistan reported also elevated influenza activity, predominantly due to influenza A(H1N1)pdm09.
- Few influenza virus detections were reported by countries in tropical Africa.
- In tropical countries of the Americas, Central America and the Caribbean, respiratory virus activity was at low levels.
- In tropical Asia, countries in southern and south east Asia overall reported ongoing low influenza activity.
- In temperate countries of the Southern Hemisphere respiratory virus activity remained low.
- National Influenza Centres (NICs) and other national influenza laboratories from 91 countries, areas or territories reported data to FluNet for the time period from 28 December 2015 to 10 January 2016 (data as of 2016-01-22 11:40:20 UTC).The WHO GISRS laboratories tested more than 65 649 specimens during that time period. 10 502 were positive for influenza viruses, of which 8481 (80.8%) were typed as influenza A and 2021 (19.2%) as influenza B. Of the sub-typed influenza A viruses, 5506 (80.2%) were influenza A(H1N1)pdm09 and 1357 (19.8%) were influenza A(H3N2). Of the characterized B viruses, 460 (49.1%) belonged to the B-Yamagata lineage and 477 (50.9%) to the B-Victoria lineage.
Detailed influenza update
For regional updates on influenza see the following links
For updates on the influenza at the human-animal interface see the following WHO web pages:
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 WHO 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.