Figure 20: Notifications of all laboratory confirmed influenza and influenza A(H1N1)pdm09, Australia, 2009, by pandemic phase and week of diagnosis or onset* This is a figure of the epidemic curve of influenza A(H1N1)pdm09 in comparison to all laboratory confirmed influenza notifications in 2009 and provides an overlay of the pandemic phases that occurred during 2009. The duration of the main wave of the pandemic was around 18 weeks, from mid-May to late September, with notifications peaking in the week ending 24 July 2009. Although influenza testing of patients with ILI continued as part routine clinical care investigations, testing was less focussed on determining the specific type of influenza infection; this is highlighted by the divergence in the epidemic curve between notifications of all laboratory confirmed cases of influenza and the pandemic specific virus.