Sept flu surveillance report for Australia
In the year to early October, 2,317 cases of laboratory confirmed influenza have been reported to the Australian National Notifiable Diseases Surveillance System (NNDSS). This was a decrease of 44% from the number of notifications in the year to date (YTD) for 2005 (4,160 cases) However, compared to the same period in 2004 (1,064 cases), this represents an increase of 66%.
National situation
·Influenza notifications continue to decrease
·Influenza and influenza-like illness notifications in 2006 have remained below 2005 trends for the majority of the season
·Influenza notifications for 2006 peaked in late August
·The highest notification rates YTD occurred in the 0-4 year old age group (41.7 per 100,000 population).
·YTD Queensland has had the highest number of notifications (1148) followed by NSW (438), Victoria (376) and Western Australia (178).
Antigenic characteristic
The World Health Organisation (WHO) Collaborating Centre for Reference and Research on Influenza in Melbourne has analysed 448 influenza strains supplied by laboratories in Australia. Of these, 21 were A (H1) strains, 280 were A (H3) strains and 147 were B strains. The majority of B strains (134) were Malaysia-like while the remainder (13) were Shanghai-like.
International summary
Overall influenza activity remains low or has decreased in both the northern and southern hemispheres. Northern hemisphere countries are expected to resume their regular influenza season reporting over the next month.
·New Zealand: Influenza activity further decreased
·Europe: Eleven countries reported no influenza activity
·Canada: Sporadic influenza activity was reported in British Columbia and Alberta, while no activity was reported in other provinces.
The National Influenza Surveillance report is compiled from a number of sentinel schemes and updated approximately every fortnight during the winter months.
