Figure 1.

Model structure and transitions through the model compartments. Susceptible individuals (S) become exposed by effective contact with any infectious (red compartments). Exposed individuals progress through three stages, E₁, E₂, and E₃, before illness onset. By testing and clinical diagnosis, both pre‐symptomatic (E₃) and unknown (U) infectious individuals can be detected and thereby enter compartment I. Severe cases requiring hospitalization (H) or intensive care (C) are included. Infectious individuals are removed from the chain of transmission when they recover (R) or die (D) from the disease. Compartments covered by the green shadow are detected and reported in data. Unknown cases (U) lead to unknown recoveries