Combined intervention We investigated five scenarios with different combinations of interventions for their effects on suppression; these included the administration of antiviral drugs for treatment (TAP/STAP) with/without school closure and with/without restraint (Table 3). In TAP and STAP, the necessary tracing period and the coverage were set to 4 days and 50%, respectively; for restraint, the rate was set to 30%. TAP should be terminated when the number of patients reaches ten persons for each ward per day because the “Pandemic Influenza Preparedness Action Plan” [5] showed that the administration of medicine to persons in close contact with a patient should be stopped after an influenza infection has spread widely. Table 3 Scenarios with different combinations of intervention measures Scenario TAP STAP School closure Restraint 1 ○ ○ 2 ○ ○ 3 ○ ○ 4 ○ ○ ○ 5 ○ ○ ○ TAP targeted antiviral prophylaxis, STAP school-age targeted antiviral prophylaxis