Pandemic (H1N1) 2009 - update 66
Weekly update (Virological surveillance data)
18 September 2009 -
Since the beginning of the pandemic (from 19 April to 5th September 2009), a total of 80 countries reported to FluNet . Total number of specimens reported positive for influenza viruses by National Influenza Centres (NICs) was 105,002. Of these, 62,719 (59.7%) were pandemic H1N1, 5899 (5.6%) were seasonal A (H1), 15,284 (14.6%) were A (H3), 17,313 (16.5%) were A (Not subtyped) and 3782 (3.6%) were influenza B.
For this reporting week (30 August to 5 September 2009), a total of 31 countries reported to FluNet. Total number of specimens reported positive for influenza viruses by NICs was 7495. Of these, 4317(57.6%) were pandemic H1N1, 283 (3.8%) were seasonal A (H1), 1612 (21.5%) were A (H3), 1167(15.6%) were A (Not subtyped), 116 (1.5%) were influenza B. On average, the pandemic A (H1N1) accounted for 58% of all flu detections (57% in northern hemisphere and 94% in southern hemisphere).
All pandemic (H1N1) 2009 influenza viruses analysed to date have been antigenically and genetically similar to A/California/7/2009-like pandemic (H1N1) 2009 virus.