In 1927, W. O. Kermack y A. G. McKendrick described the first mathematical model for infectious diseases using a set of differential equations. This model is called SIR because of the three states one individual can have.

These states are:

• Susceptible: The individuals that can be infected by the disease
• Infected: The individuals that have been infected and suffer the disease.
• Recovered: The individuals that recovered from the disease and have become…