WHO : Influenza update - 8 November 2010

From WHO, the latest influenza update. Thanks to Mike Coston at Avian Flu Diary for this.

" Influenza - Update 120

8 November 2010 - Summary:

Worldwide, overall influenza activity remained low, except in parts of the tropics, most notably in Southeast Asia, and to a lesser extent in the tropical areas of the Americas. After late winter and springtime influenza epidemics in several countries of the temperate southern hemisphere, influenza activity has returned to near or below baseline in most places. Notably, however, a recent post-season rise in cases has been noted across parts of southern Africa associated with localized outbreaks of influenza H1N1 (2009) virus. Seasonal influenza A(H3N2) viruses continued to be the predominant circulating type or subtype of influenza viruses worldwide, however, in addition, in many countries there has been co-circulation of seasonal influenza B viruses and to a lesser extent, influenza H1N1 (2009) viruses. The latter has been recently predominant in a limited number of countries, including in India.

Countries in the temperate zone of the Southern Hemisphere

In Chile, an unusually late winter and springtime influenza epidemic, characterized by predominance of circulating seasonal influenza A (H3N2) viruses, and to a lesser extent seasonal influenza B and H1N1 (2009) viruses, appears to have largely subsided. A similarly timed influenza epidemic was also observed in Paraguay and Uruguay. In Argentina, however, little winter and springtime influenza activity was observed during 2010, with influenza B viruses accounting for the majority of sporadic influenza virus detections.

In South Africa, the 2010 winter influenza season, characterized by a predominance of seasonal influenza B viruses, and to lesser seasonal A(H3N2) viruses, had largely concluded by the end of September 2010 but was followed by a mild resurgence of influenza activity (with a similar distribution of influenza viruses) during October 2010. In neighboring Namibia, there have been reports of school and community outbreaks of influenza H1N1 (2009) during October 2010."