05 October 2015, - Update number 247, based on data up to 20 September 2015
Globally, influenza activity generally decreased or remained low, with only a few countries reporting elevated respiratory illness levels.
- In the Northern Hemisphere, influenza activity continued at low, inter-seasonal levels with sporadic detections. Increased respiratory syncytial virus (RSV) activity was reported in the United States of America (USA).
- Few influenza detections were reported by countries in Africa. In Eastern Africa, in countries with reported influenza activity, influenza type A viruses predominated. In Western Africa, influenza activity decreased overall.
- In tropical countries of the Americas, Central America and the Caribbean, influenza activity remained at low levels, with the exception of Cuba, where high numbers of severe acute respiratory infections (SARI) were still reported, associated with influenza A(H1N1)pdm09 virus and RSV. Colombia experienced slightly elevated acute respiratory activity (ARI) in recent weeks with elevated RSV activity.
- In tropical Asia, countries in Southern and South East Asia reported low influenza activity overall except in India and Lao People’s Democratic Republic where increased activity mainly due to A(H1N1)pdm09 virus in India and A(H3N2) virus in Lao PDR continued to be reported. Influenza activity declined in southern China.
- In temperate South America, respiratory virus activity decreased or remained low in general. However, ILI activity remained elevated in Chile with increasing influenza A(H1N1)pdm09 detections.
- In South Africa, influenza activity remained at low levels with influenza type B viruses predominating in recent weeks.
- In Australia, influenza activity in general seemed to be past the peak except in South Australia where it continued to rise with predominantly influenza B virus followed by influenza A(H3N2) virus detections. In New Zealand, influenza activity may have peaked in the second week of August with influenza A(H3N2) and B viruses predominating during the season. ILI activity was still above the seasonal threshold but below the alert threshold.
- The vaccine recommendation for the 2016 southern hemisphere winter season was made and can be consulted at this link below:
- National Influenza Centres (NICs) and other national influenza laboratories from 71 countries, areas or territories reported data to FluNet for the time period from 07 September 2015 to 20 September 2015* (data as of 2015-10-01 12:17:00 UTC).The WHO GISRS laboratories tested more than 35084 specimens during that time period. 2096 were positive for influenza viruses, of which 1722 (82.2%) were typed as influenza A and 374 (17.8%) as influenza B. Of the sub-typed influenza A viruses, 305 (21.3%) were influenza A(H1N1)pdm09 and 1124 (78.7%) were influenza A(H3N2). Of the characterized B viruses, 110 (92.4%) belonged to the B-Yamagata lineage and 9 (7.6%) to the B-Victoria lineage.
Detailed influenza update
Recommended composition of influenza virus vaccines for use in the 2016 southern hemisphere winter season
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.