Compartmental Frameworks The foundation of epidemic theory is the SIR model, formulated by Kermack and McKendrick, which divides a population into three compartments: Susceptible, Infectious, and Recovered (or Removed). Transitions between these states are governed by differential equations where the rate of new infections is proportional to the contact between susceptible and infectious individuals. Variations include the SEIR model (adding an "Exposed" latent period) and SIS model (where individuals return to susceptibility after recovery).

Deterministic vs. Stochastic Models

• Deterministic Models: Utilizing ordinary differential equations (ODEs), these models describe the average behavior of large populations. They assume fixed rates and continuous variables, predicting that if transmission conditions are met, the disease will rea ...