Influenza update - 285
20 March 2017, - Update number 285, based on data up to 05 March, 2017
Influenza activity in the temperate zone of the northern hemisphere appeared to decrease. Influenza activity in many countries especially in East Asia and Europe already peaked. Worldwide, influenza A(H3N2) virus was predominant. In South Asia influenza activity with mainly H1N1 has been increasing. The majority of influenza viruses characterized so far were similar antigenically to the reference viruses contained in vaccines for use in the 2016-2017 northern hemisphere influenza season. Nearly all tested viruses collected recently for antiviral sensitivity were susceptible to the neuraminidase inhibitor antiviral medications.
- In North America, overall influenza and other respiratory virus activity decreased in Canada and United States of America. Influenza activity slightly increased in Mexico with influenza A(H1N1)pdm09 virus predominating.
- In Europe, influenza activity appeared to decrease with influenza A (H3N2) and influenza B viruses predominant in the region. Detections of influenza B virus increased in the recent weeks. Persons aged over 65 years continued to be reported as most frequently associated with severe disease from influenza infection.
- In East Asia, influenza activity continued to decrease with influenza A(H3N2) virus predominant.
- In Western Asia, influenza activity continued to decrease with influenza A(H3N2) and B viruses co-circulating in the region.
- In Southern Asia, influenza activity continued to increase in India, the Maldives and Sri Lanka, with mainly influenza A(H1N1)pdm09 virus reported followed by influenza B virus.
- In South East Asia, influenza activity remained low.
- In Northern Africa, low influenza activity was reported in Tunisia, with influenza A(H3N2) and influenza B virus co-circulating.
- In West Africa, influenza activity continued to be reported in Ghana and Mali, with influenza B being the main virus detected. In Eastern Africa, influenza activity was reported in Ethiopia and Mauritius with influenza A(H3N2) virus predominant.
- In the Caribbean countries and Central America, influenza and other respiratory virus activity remained low in general.
- In tropical South America, influenza and other respiratory virus activity remained low, although RSV activity remained elevated in Colombia.
- In the temperate zone of the Southern Hemisphere, influenza activity was at inter-seasonal levels. National Influenza Centres (NICs) and other national influenza laboratories from 94 countries, areas or territories reported data to FluNet for the time period from 20 February 2017 to 05 March 2017 (data as of 2017-03-17 09:50:51 UTC).The WHO GISRS laboratories tested more than 156226 specimens during that time period. 34376 were positive for influenza viruses, of which 26581 (77.3%) were typed as influenza A and 7795 (22.7%) as influenza B. Of the sub-typed influenza A viruses, 651 (8.1%) were influenza A(H1N1)pdm09 and 7392 (91.9%) were influenza A(H3N2). Of the characterized B viruses, 614 (71.4%) belonged to the B-Yamagata lineage and 246 (28.6%) to the B-Victoria lineage.
- The vaccine recommendation for the 2017-2018 northern hemisphere influenza season was made and can be consulted at this link below:
Recommended composition of influenza virus vaccines for use in the 2017-2018 northern hemisphere influenza season
Detailed influenza update
Source of data