Influenza

Influenza update

29 June 2015, - Update number 240, based on data up to 14 June 2015

Summary

Globally, influenza activity has decreased from its peak of influenza activity in early 2015 to low levels in the Northern Hemisphere while there were increases in activity in the Southern Hemisphere.

  • In North America, influenza activity was at low, inter-seasonal levels. Influenza type B continued to be the predominant strain in circulation in recent weeks.
  • In Europe, influenza activity remained low with influenza B predominant in recent weeks
  • In northern Africa, influenza activity remained at low levels in most countries with influenza A activity being predominant throughout the whole season.
  • In western Asia, most countries reported decreasing influenza activity remaining at low levels in recent weeks.
  • In the temperate countries of Asia, influenza activity remained at low levels.
  • In tropical countries of the Americas, low inter-seasonal levels of influenza activity were reported in most countries except Peru where low levels of influenza type A circulation was detected.
  • In tropical Asia, increased influenza activity was reported from Hong Kong(Special Administrative Region, China), Singapore, southern China, Viet Nam, and Sri Lanka with influenza type A viruses predominating in recent weeks.
  • In the Southern Hemisphere, influenza activity increased in most of the regions but remained at low levels. However, South Africa reported high influenza activity with influenza A(H1N1)pdm09 and A(H3N2) co-circulation in recent weeks.
  • National Influenza Centres (NICs) and other national influenza laboratories from 53 countries, areas or territories reported data to FluNet for the time period from 31 May 2015 to 13 June 2015 (data as of 25/06/2015 12:05 UTC). The WHO GISRS laboratories tested more than 23 577 specimens during that time period. 1620 were positive for influenza viruses, of which 1117 (69%) were typed as influenza A and 503 (31%) as influenza B. Of the sub-typed influenza A viruses, 172 (22.8%) were influenza A(H1N1)pdm09 and 582 (77.2%) were influenza A(H3N2). Of the characterized B viruses, 69 (83.1%) belonged to the B-Yamagata lineage and 14 (16.9%) to the B-Victoria lineage.

Detailed influenza update

Influenza surveillance outputs

Seasonal 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.

Share

If you wish to be notified when this page is updated send an e-mail to fluupdate@who.int