African Trypanosomiasis causes many problems in both public health
and agricultural production in Africa. Tsetse flies transmit Trypanosomiasis;
targets for the fly are vertebrates, including humans. Humans and
animals cannot be infected through direct contact with each other,
but Tsetse flies are a vehicle for the spread of the disease. In the
north of Cameroon, cattle are infected more than humans but in the
south of Cameroon the opposite trend is observed.
We examine the different levels of disease prevalence in the two
host types in the north and the south. Because the population in Cameroon
is unevenly distributed, we hypothesize that the cause of this phenomenon
is that flies have a greater opportunity to bite a more abundant host.
We introduce two models of Trypanosomiasis in Cameroon – an SIS
model and a host preference model. We use the SIS model to determine
whether Trypanosomiasis can invade the population. The host preference
model rests on the assumption that Tsetse flies prefer more abundunt host, and borrows the concept of functional response from ecology.
Finally, we construct a new SIS model by combining our basic SIS model
and the host preference model. Further numerical work on the
model is needed to assess whether it explains the different levels
of disease prevalence observed in Cameroon.