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Ngiela, J.

Publications and source records attributed to Ngiela, J..

2 recordsLinked to original sources

Multimodal interactions in Stomoxys navigation reveals synergy between olfaction and vision.

Stomoxys flies exhibit an attraction towards objects that offer no rewards, such as traps and targets devoid of blood or nectar incentives. This behavior provides an opportunity to develop effective tools for vector control and monitoring. However, for these systems to be sustainable and eco-friendly, the visual cues used must be selective in attracting the target vector(s). In this study, we modified the existing blue Vavoua trap, originally designed to attract biting flies, to create a deceptive host attraction system specifically biased towards attracting Stomoxys. Our research reveals that Stomoxys flies are attracted to various colors, with red proving to be the most attractive and selective color for Stomoxys compared to other colors tested. Interestingly, our investigation on cattle-Stomoxys interaction demonstrates that Stomoxys flies do not have preference for a specific livestock fur color phenotype, despite variation in spectrum. To create a realistic sensory impression of the trap in the Stomoxys nervous system, we incorporated olfactory cues from livestock host odors that significantly increased trap catches. The optimized novel nanopolymer bead dispenser capable of effectively releasing the attractive odor, carvone + p-cresol, with strong plume strands, longevity. Overall, red trap baited with nano polymer beads dispenser is environmentally preferred.

ecology↗

Molecular characterization of pathogenic African trypanosomes in biting flies and camels in surra-endemic areas outside the tsetse fly belt in Kenya

BackgroundAfrican animal trypanosomosis is becoming prevalent beyond its traditionally defined geographical boundaries and is a threat to animals beyond the tsetse belts in and outside Africa. However, knowledge of infections with clinically important trypanosome species and their diversity among field-collected hematophagous biting flies and domestic animals is limited mainly to tsetse and their mammalian hosts in tsetse-infested areas. This study aimed to examine the presence of trypanosomes in both biting flies and domestic animals outside the tsetse belt in northern Kenya, potential mechanical vector species, and their host-feeding profiles. MethodsWe screened for pathogenic African trypanosomes in blood samples from domestic animals and field-trapped flies by microscopy and sequencing of internal transcribed spacer (ITS1) gene PCR products. We sequenced kinetoplast maxicircle genes to confirm Trypanosoma brucei detection and the RoTat 1.2 and kinetoplast minicircle genes to differentiate type-A and type-B Trypanosoma evansi, respectively. Further, we identified the hosts that field-trapped flies fed on by PCR-HRM and sequencing of 16S rRNA genes. ResultsHippobosca camelina, Stomoxys calcitrans, Tabanus spp., and Pangonia rueppellii are potential vectors of trypanosomes outside the tsetse belt in Marsabit County, northern Kenya. We identified Trypanosoma spp., including Trypanosoma vivax, T. evansi, T. brucei, and T. congolense in these biting flies as well as in camels (Camelus dromedarius). Trypanosomes detected varied from single up to three trypanosome species in H. camelina and camels in areas where no tsetse flies were trapped. Similar trypanosomes were detected in Glossina pallidipes collected from a tsetse-infested area in Shimba Hills, coastal Kenya, showing the wide geographic distribution of trypanosomes. Furthermore, we show that these biting flies acquired blood meals from camels, cattle, goats, and sheep. Phylogenetic analysis revealed diverse Trypanosoma spp. associated with variations in virulence and epidemiology in camels, which suggests that camel trypanosomosis may be due to mixed trypanosome infections rather than only surra (T. evansi), as previously thought.

pathology↗