Population Dynamics of Sleeping Sickness: A Microsimulation

Abstract

A microsimulation model of the spread of Gambian sleeping sickness is described. The model focuses on the randomness of epidemic trajectories brought about merely by the random nature of fly bites on humans. There is a high level of variability in the trajectories, primarily due to the small sizes of the populations involved. There is an inverse relationship between the probability of initial extinction and the size of an epidemic flare-up when the disease takes hold. When a stream of one infected fly enters the focus every 3 days, a low-level endemic can be sustained with less variability. Implications and further subjects of study are briefly discussed.