on week 41) after the first cases were reported on week 29 in Scotland (Figure 7a ). Clearly, here it does not perform as well as it does with the simulated pandemic data. In the next section we discuss possible reasons for this poor performance. The Mov-Avg Cusum method, which was the worst performer among the three methods using simulated pandemic data, also detects the pandemic in week 41 (Figure 7b ). Both methods outperform the ILI rate threshold method by 1 week (Figure  7c ).