Yellow Fever: Advanced Exercises

The following exercises are designed for the student with advanced interest in epidemiology.

1. Expand the Model to Simulate Mosquito Control Programs

Expand the model to simulate the impact of a program to reduce the size of the mosquito population by the application of larvacide. You may assume that the larvacide will reduce the number of emerging mosquitoes, but it will not directly affect the adult population. Include the start date and the percent reduction in emerging mosquitoes as program parameters that may be specified by the model user.

2. Summary of Mosquito Control Programs

Use the expanded model from the 1st exercise to experiment with varying start dates and varying magnitudes. Summarize your results with a parameter space diagram like the diagram in Figure 17.10. Place the start date on the horizontal axis and the magnitude of the mosquito reduction on the vertical axis. Label the space according to whether the control programs would be successful or unsuccessful. Define success as limiting the number of people impacted by the epidemic to 500 or less.

3. Simulate Detection and Isolation Programs

Assume that it is possible to detect the disease during the 4.5 day incubation period and that it is possible to isolate the infected people before they reach the contagious stage. Add the new stocks and flows needed to move a fraction of these people into a separate category that is isolated from the mosquito population. As in the previous exercise, allow the start date and the magnitude of isolation to be specified by the model user. Experiment with the new model to learn the program parameters necessary to limit the number of people impacted by the epidemic to 500 or less.