Table 2. Number of seasons detected from 2009 to 2015 using the median value from all weeks as the seasonal threshold, with either the first-week-declaration rule or two-consecutive-week-declaration rule for the three parameters: proportion ILI, proportion positive and composite.
| Season* | Proportion ILI | Proportion positive | Composite | |||
|---|---|---|---|---|---|---|
| 1st week** | 2nd week*** | 1st week** | 2nd week*** | 1st week** | 2nd week*** | |
| 2009/2010 | 5 | 2 | 3 | 1 | 2 | 1 |
| 2010/2011 | 7 | 3 | 1 | 1 | 1 | 1 |
| 2011/2012 | 6 | 2 | 4 | 1 | 1 | 1 |
| 2012/2013 | 7 | 2 | 3 | 3 | 3 | 1 |
| 2013/2014 | 9 | 4 | 6 | 1 | 6 | 1 |
| 2014/2015 | 10 | 5 | 3 | 1 | 4 | 1 |
* Starts on week 18 and ends on week 17 of the following year.
** Start or end of season declared on the first week threshold was crossed.
*** Start or end of season declared when threshold is crossed for two consecutive weeks.