Weekly Virological Update on 19 August 2010
Trend of proportions of different type and subtype influenza viruses
Summary on week 31
Global Virological Surveillance
Overall influenza activity has remained low. Co-circulation of pandemic A(H1N1), A(H3N2) and influenza B viruses was reported from Australia, China, Mauritius, Singapore and South Africa. Globally 33.4% of the sub-typed influenza A viruses were pandemic influenza A(H1N1) with circulation as predominant strain locally in New Zealand and India. Sporadic influenza B and/or A(H3N2) activity has been observed in some countries.
For the week 1 August to 7 August 2010. National Influenza Centres (NICs) from 23 countries reported data to FluNet. Of the total 718 specimens reportedly positive for influenza viruses, 585 (81.5%) were typed as influenza A and 133 (18.5%) as influenza B.
WHO, through the GISN, continues monitoring the global circulation of influenza viruses, including pandemic, seasonal and other influenza viruses infecting, or with the potential to infect humans.*
* Some NICs report data to FluNet retrospectively and updates of previous data with new results are frequent.