As important as tsetse mapping is the study of Trypanosomosis occurrence (prevalence) and its disease expression (i.e. anaemia: the most important symptom of Trypanosomosis). Nonetheless, there are very few known records of the systematic mapping of trypanosome distribution and prevalence rates. This is in part due to the fact that flies abundance was expected to reflect disease risk. Thus, Trypanosomosis surveys were often not carried out. Among those few studies, surveys in south-west Zambia revealed that the extent of the Trypanosomosis problem covered a wider area than expected from historical fly distribution data alone. In some cases, herds were systematically sampled to map parasite distribution and prevalence as well as average anaemia in herds. When such data sets are available, it is possible to use GIS analysis to map epidemiological patterns and show their correlation with physical features such as the drainage system.

In mapping trypanosome and anaemia distribution, it can be argued that RS gives more accurate results for the disease itself than for anaemia, since many causes other than Trypanosomosis may result in anaemia.