Influenza

Influenza update - 302

13 November 2017, - Update number 302, based on data up to 29 October 2017

Summary

Influenza activity remained at low levels in the temperate zone of the northern hemisphere. Declining levels of influenza activity were reported in the temperate zone of the southern hemisphere and in some countries of South and South East Asia. In Central America and the Caribbean, low influenza activity was reported in a few countries. Worldwide, influenza A(H3N2) and B viruses accounted for the majority of influenza detections.

  • In North America, overall influenza activity increased slightly but remained low, with detections of predominantly influenza A(H3N2) and B viruses in the past weeks.
  • In Europe, influenza activity remained low, with detections of predominantly influenza A(H3N2) and B viruses.
  • In Western Asia, influenza activity was low in general. In Qatar, influenza activity remained high with all seasonal subtypes co-circulating.
  • In Central Asia, influenza like illness (ILI) and severe acute respiratory infection (SARI) indicators appeared to increase in Kazakhstan, Tajikistan and Uzbekistan.
  • In East Asia, influenza activity remained low in general. In Northern China, influenza A(H3N2) detections increased slightly in recent weeks.
  • In South East Asia, influenza activity continued to decrease, with influenza A(H3N2) and B viruses most frequently detected.
  • In Southern Asia, influenza activity remained low in general. In India, influenza A(H1N1)pdm09 and A(H3N2) detections decreased in recent weeks.
  • In Northern Africa, there were no reports during the reporting period.
  • In Western and Middle Africa, influenza detections continued to be reported, with all seasonal influenza subtypes present in the region. In Eastern Africa, little to no influenza activity was reported.
  • In the Caribbean and Central American countries, respiratory illness indicators and influenza activity remained low in general but respiratory syncytial virus (RSV) activity remained high in several countries.
  • In the tropical countries of South America, influenza and RSV activity remained at low levels.
  • In the temperate zone of the Southern Hemisphere, influenza activity appeared to have decreased overall.
  • National Influenza Centres (NICs) and other national influenza laboratories from 101 countries, areas or territories reported data to FluNet for the time period from 16 October 2017 to 29 October 2017 (data as of 2017-11-10 04:06:39 UTC). The WHO GISRS laboratories tested influenza viruses, of which 2,954 (72.3%) were typed as influenza A and 1,134 (27.7%) as influenza B. Of the sub-typed influenza A viruses, 318 (13.8%) were influenza A(H1N1)pdm09 and 1,985 (86.2%) were influenza A(H3N2). Of the characterized B viruses, 485 (81.1%) belonged to the B-Yamagata lineage and 113 (18.9%) to the B-Victoria lineage.

Detailed influenza update

Seasonal update




Source of data