Abstract

Nurhan Albayrak*, Meral A. Ciblak , Ayse Basak Altas, Melis Kanturvardar, Yavuz Odabas, Bahadir Sucakli, Gulay Korukluoglu , Selim Badur and Mustafa Ertek

National influenza surveillance was performed by two institutions in Turkey, Refik Saydam National Public Health Agency (RSNPHA) and Istanbul Faculty of Medicine (IFM), which both are National Influenza Reference Laboratories. RSNPHA received samples from 9 sentinel Provinces and IFM received samples from 5 sentinel Provinces. We report the 2008 to 2009 surveillance results from October 2008 - May 2009. As many as 1,980 clinical specimens received from 14 sentinel and non-sentinel Provinces of which 257 nasal-nasopharyngeal samples were positive for influenza viruses. The predominant virus type was influenza B (67.5% of total detections), and the dominant sub- type among Influenza A viruses was H3 (98.8%). Influenza-like illness (ILI) activity started around the 42nd week, decreased around the 23nd week and the laboratory confirmed seasonal Influenza activity started around 48th week and ended around 22nd week. The 2008 - 2009 influenza seasons in Turkey was characterized by moderate clinical activity and a dominance of influenza B. In Hemagglutination inhibition (HI) test, the majority of influenza A/H3 viruses were closely related to the vaccine virus strain of the 2008 to 2009 season, Influenza A Brisbane/10/2007 (H3N2) like virus. However, Influenza B viruses were antigenically different from the vaccine strain and more closely related to Influenza B Malaysia/2560/2004 (Victoria lineage). It is concluded that knowledge about the influenza activity in Turkey, which is at the crossroads of Europe and Asia, contributed to monitoring the movement of influenza virus epidemiology.