The distribution of bovine trypanosomosis in Zimbabwe and an evaluation ofthe value of an anti-trypanosomal antibody detection ELISA as a tool for monitoring the effectiveness of tsetse control operations

Tsetse have been cleared from large areas of Zimbabwe during the past 65 ye ars. In most areas, they are prevented from re-invading cleared areas by ba rriers of odour-baited, insecticide-treated targets. A trypanosomosis surve y was conducted to determine the effectiveness of such barriers against re- invasion and to confirm the absence of tsetse in areas where they had previ ously been eradicated. Parasitological diagnostic methods and an anti-trypa nosomal antibody detection enzyme-linked immunosorbent assay (antibody ELIS A) were used. The prevalence of trypanosomal infections in the tsetse-clear ed areas was generally low. However, the prevalence of anti-trypanosomal an tibodies was unexpectedly high in some areas. This high proportion of cattl e with antibodies could, in most cases, be explained by recent or historic information on the distribution and density of tsetse. The results from the survey demonstrated the value of anti-trypanosomal antibody detection as a n additional sensitive tool for monitoring the effectiveness of tsetse cont rol operations.