Figure 2.

Disease burdens of a simulated population over time. Patients whose infections exceed the “symptom threshold” (a mathematical benchmark) are tracked until death (when the bacillary burden exceeds a mathematical “death threshold”, colored in red) or self-resolution (when the burden falls below the “symptom threshold”, colored in green). Patients who continue to experience active tuberculosis (ie, without exceeding the death threshold or experiencing self-resolution) after 5 years are colored in blue. Patients who never develop symptomatic disease (ie, never surpass the symptom threshold) are plotted in grey. All disease burdens depicted were generated using the same model parameters and represent the population variability in progression/recovery rates as well as stochastic transitions between phases of infection. The disease burden of an arbitrary Patient A quantitatively depicts the progression of disease diagrammed graphically in Figure 1C; note that the rate (slope) of progression for Patient A is the same throughout her life (ie, both before and after recovery).