Pandemic cost per capita, attack rate, and reproduction number for different severities of pandemic influenza in the base case scenario of no vaccine intervention.

Pandemic cost per capita is the average cost of influenza related health outcomes among infected individuals for death, hospitalization, outpatient visit, and ill but not seeking medical care. The attack rate is the proportion of population infected by influenza during the influenza pandemic. Reproduction number is the number of secondary cases caused by the index case in a susceptible population.