This is a system model of the spread of the disease in a population. It tracks the proportion of
the population that is infected by the disease on any given day. The infection probability,
recovery rate, loss of immunity fraction, birth rate, and death rate are user-controlled
parameters. A graph depicts the change in the number of people who are susceptible, infected and
recovered over the progression of the sickness.

What can this Model be used to teach?

Understand the relationship between the proportion of the population that is healthy and the
spread of the disease

Understand the effect of each parameter on the populations over time