Here are the specifications for the Epidemic model:
Create 300 healthy turtles and set their color to blue
Create 3 sick turtles and set their color to red.
Create a transmission rate slider with range from 0 to 100
Use the value in the transmission rate slider as the probability of passing on the disease when a sick and a healthy turtle collide.
Next, add a recovery slider. Use the value in the recovery slider as the probability that recovering from the disease at each step. Then create a recovery procedure that can make a turtle healthy (or blue).