25 August 2014 - Update number 218
Globally influenza activity continued to increase in the southern hemisphere, and remained low elsewhere.
- In Europe and North America, overall influenza activity remained at inter-seasonal levels.
- In Africa and western Asia, influenza activity was low.
- In eastern Asia, influenza activity reached inter-seasonal levels in most countries with influenza A(H3N2) and influenza B virus predominating. Influenza A(H3N2) activity continued in south China.
- In the southern hemisphere, influenza activity continued to increase in most countries. In the temperate zone of South America, influenza activity mainly associated with A(H3N2) virus continued to increase, while respiratory syncytial virus activity declined. In Australia and New Zealand, the influenza season appeared to have started with ILI and the number of influenza virus detections increased. Influenza A(H1N1)pdm09 was the most common detected virus. In South Africa the influenza detection rate increased with A(H3N2) the most frequently detected.
- Based on FluNet reporting (as of 25 August 2014, 11:25 UTC), during weeks 31 to 32 (27 July 2014 to 9 August 2014), National Influenza Centres (NICs) and other national influenza laboratories from 51 countries, areas or territories reported data. The WHO GISRS laboratories tested more than 26 644 specimens. 4014 were positive for influenza viruses, of which 3645 (90.8%) were typed as influenza A and 368 (9.2%) as influenza B. Of the sub-typed influenza A viruses, 534 (16.8%) were influenza A(H1N1)pdm09 and 2636 (83.2%) were influenza A(H3N2). Of the characterized B viruses, 37 (94.9%) belonged to the B-Yamagata lineage and 2 (5.1%) to the B-Victoria lineage.
Full 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.