Responses of Glossina fuscipes fuscipes to visually attractive stationary devices baited with 4-methylguaiacol and certain repellent compounds in waterbuck odour

Author summary Tsetse flies are divided into three taxonomic groups: morsitans, palpalis and fusca. Flies from the morsitans and palpalis groups are the main vectors of trypanosoma parasites that cause human and animal African trypanosomiasis. The chemical 4-methylguaiacol and waterbuck (Kobus defassa), a known non-preferred host of tsetse, body odour blend (pentanoic acid, guaiacol, δ-octalactone and geranylacetone), have been shown to repel morsitans group species G. pallidipes and significantly reduce levels of animal African trypanosomiasis. However, these repellents have not been evaluated against other groups of tsetse, for example, those in the palpalis group. Here, we show that visually attractive stationary devices (biconical traps and sticky small targets) when baited with these repellent compounds and some of their blends significantly repel G. f. fuscipes, one of the important vectors of human sleeping sickness belonging to the palpalis group. The results provide the foundation for future studies of these compounds on their repellency of other Glossina species and their use in ‘push-pull’ strategies for manipulation of attraction to human and animal hosts and also in disease reduction strategies especially for riverine tsetse flies which are major vectors of parasites that cause sleeping sickness.