Increased sensitivity to a natural pyrethrum extract of Trypanosoma-infected Glossina morsitans

Topical application of a natural pyrethrum extract on male and pregnant female Glossina morsitans morsitans resulted in higher mortality for flies infected with Trypanosoma brucei brucei than for uninfected control flies. Infected males showed a significantly higher mortality while infected pregnant females showed a marginally significant increase in mortality. Results support the hypothesis that infected flies are less healthy than uninfected flies. Results also parallel previous findings using endosulfan as the topical applicant and exclude the likelihood that the results were because of a peculiar effect of endosulfan.