Fig. 4

Forecast of seasonal HFMD outbreaks in Tokyo between the years 2009 and 2018. In each subgraph, the left y-axis is the average number of patients in each clinic and the right y-axis is the L-DNM score that was calculated based on a 5-week sliding window scheme; the x-axis represents the period from first week of the year to last week of the year. Besides, the markers of different colors and shapes are used to identify warning signals or outbreak points. Clearly, when the actual number of clinic visits has not increased significantly, significant changes in L-DNM scores have been detected, indicating the presence of pre-outbreak signals