(A) Snapshot of a numerical simulation of the model. Spheres represent agents moving in a square section of 250 m × 250 m. The color of each agent represents the class to which its belong: white for susceptible and immunized, green for infected, orange for symptomatic, and yellow for quarantined. The concentration of stable SARS-CoV-2 on hard surfaces is represented using the gradient of the green color. (B) The clinical course of COVID-19 patients in the model.