Base mortality probabilities (μ i in (2)) were found using the statistics recommended by the Working Group on Pandemic Preparedness and Influenza Response [52] . This data shows the percentage of mortality for age-based high-risk cases (HRC) ( Table 3 , columns 1-3). Mortality probabilities (column 4) were estimated under the assumption that highrisk cases are expected to account for 85% of the total number of fatalities, for each age group [52] .