Sensitivity analysis: Age distribution.

<p>Age distribution was calculated as a function of duration of sterile and clinical immunity and <i>R_c</i>. Probabilities of acquiring immunity were 0.184 for sterile or clinical immunity and the duration of infant refractoriness/non-exposure was 8±6 months. Within each graph the observed distribution (black diamonds) and predicted distribution is plotted vs log age (years). <i>R_c</i> was 2, 3, 3.3, 4 and 5 for the purple, blue, green, orange and red plots, respectively.