Figure 1
Visualization of simulated epidemic dynamics from year 4, generated using set.seed(656) as specified in Section ‘Population Simulation’. The top panel shows the number of new infections over time, demonstrating the characteristic epidemic curve with a peak of approximately 1500 daily cases around day 150. The bottom panel shows the corresponding reported cases after applying the 2% reporting rate and 7-day reporting delay, resulting in more variable daily counts with a maximum of 44 reported cases. The epidemic starts on day 38, showing an initial slow growth phase followed by exponential growth and eventual decline.
Figure 2
Comparison of epidemic indicators and alert timings for year 4, generated using set.seed(656) as specified in Section ‘Population Simulation’. The grey area shows daily school absenteeism percentage, while the black area represents laboratory confirmed cases (2% of true cases). The vertical dashed line indicates the reference date (epidemic start), and coloured squares below show the timing of alerts generated by different metrics. The clustering of alerts from different metrics shortly before the reference date suggests good agreement between methods, while their placement before the major increase in cases demonstrates the system’s early warning capability. Notably, both weighted metrics (WAATQ, WFATQ) generate alerts at similar times to their unweighted counterparts, indicating robust detection regardless of weighting scheme.