Part One
The third quartile values for the number of IPs detected by Days 14, 21, 28 and 35 for the 10,000 simulated outbreaks were 20, 25, 29 and 32 respectively. Based on assessing the EDR values at these same time points plus expert opinion, it was decided that 5-day EDRs >= 2.0 between days 11 – 14 inclusive indicated a large outbreak was brewing, while recording EDR >= 1.5 between days 15 – 35 inclusive also indicated a large outbreak was possible. These values were combined to create the complex EDI as shown in Table 3. If either the number of IPs or the EDR exceeded the stated thresholds during the specified time periods, the trigger fired.