Figure 3.5.1 is a line graph that demonstrates that from 2007 to 2011, there were marked increases in the winter seasonal peaks in influenza notifications relative to previous years with a very large peak in influenza notifications between May and September 2009 related to the H1N1 influenza pandemic. Also, there was a large peak in hospitalisations for influenza code J09 (identified H1N1) in the winter months of 2009 with smaller peaks in 2010 and 2011. Hospitalisations for other influenza (J10, J11) also had a larger than average peak in winter 2009. However, in 2010 and 2011, hospitalisations for other influenza (J10, J11) returned to levels seen in the years prior to 2007.