Publications by authors named "Torto B"

Background: Surveillance of the host-anopheline mosquitoes' interaction is important for assessing malaria transmission risk and guiding vector control. We assume that changes in malaria vector species' feeding habits, as well as the surrounding environment, have a substantial impact on varied malaria transmission. In this study, we determined the vertebrate host feeding patterns of anopheline mosquitoes to characterize entomologic risk factors for malaria in Jabi Tehnan, Northwestern Ethiopia.

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Phlebotomine sand flies are vectors of multiple human pathogens but are well known for enabling transmission of Leishmania parasites, which cause leishmaniasis, the visceral form constituting a serious public health disease and a second parasitic killer in the world after malaria. Sensory ecology shapes sand fly behavior, including host seeking for a blood meal, nectar foraging, oviposition, and reproduction, which directly impacts on disease transmission. As such, knowledge of sand fly sensory ecology, including olfactory and physical (visual, tactile, thermal, and acoustic) cues, is essential to enable their exploitation in the development of novel tools for sand fly surveillance and control.

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Article Synopsis
  • - Improved tools like DNA barcoding reveal that mosquitoes, specifically malaria vectors in Kenya, feed on plants much more than previously thought, with a 41% feeding rate versus a low 2.8% through traditional methods.
  • - The study found that the presence of the malaria parasite Plasmodium falciparum affects the sugar levels in mosquitoes, and that these insects primarily feed on acacia plants, particularly Vachellia tortilis.
  • - The findings point to the important role of nutrient content and scent from plants in attracting mosquitoes, and these insights could help develop effective strategies for controlling malaria through odor-based traps and bait.
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Tsetse flies are vectors of the parasite trypanosoma that cause the neglected tropical diseases human and animal African trypanosomosis. Semiochemicals play important roles in the biology and ecology of tsetse flies. Previous reviews have focused on olfactory-based attractants of tsetse flies.

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Among the factors affecting the effectiveness of malaria control is poor knowledge of the entomologic drivers of the disease. We investigated anopheline populations as part of a baseline study to implement house screening of windows and doors as a supplementary malaria control tool towards elimination in Jabi Tehnan district, Amhara Regional State of Ethiopia. The samples were surveyed monthly using CDC light traps between June 2020 and May 2021.

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Accurate knowledge of blood meal hosts of different mosquito species is critical for identifying potential vectors and establishing the risk of pathogen transmission. We compared the performance of Miseq next generation sequencing approach relative to conventional Sanger sequencing approach in identification of mosquito blood meals using genetic markers targeting the 12S rRNA and cytochrome oxidase I (COI) genes. We analysed the blood meals of three mosquito vector species (Aedes aegypti, Aedes simpsoni s.

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The zoophytophagous mirid predator Nesidiocoris tenuis and the ectoparasitoid Stenomesius japonicus are important biological control agents for several agricultural pests including the invasive leafminer, Phthorimaea absoluta, a destructive pest of Solanaceous crops especially tomato in sub-Saharan Africa. However, little is known about how feeding by N. tenuis can influence the tritrophic interactions in the tomato plant.

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Introduction: In sub-Saharan Africa, the invasive South American leafminer Phthorimaea absoluta is the most damaging tomato pest. Females of the pest can reproduce both sexually and through parthenogenesis and lay their eggs on all tomato plant parts. The mirid predator Nesidiocoris tenuis, a biological control agent for the pest, is also a tomato pest when prey population is low.

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This study investigates the efficacy of three different olfactory cues - cyclohexanone, linalool oxide (LO), and 6-methyl-5-heptan-2-one (sulcatone) - in attracting Aedes aegypti, the primary vector of dengue, using BG sentinel traps in a dengue-endemic area (urban Ukunda) in coastal Kenya. Two experiments were conducted. Experiment 1 compared solid formulations of the compounds in polymer beads against liquid formulations with hexane as the solvent.

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In the Americas, the fall armyworm (Spodoptera frugiperda) exists in two genetically distinct strains, the corn (C) and rice (R) strains. Despite their names, these strains are not associated with host plant preferences but have been shown to vary in pheromone composition and male responses. Recently, S.

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Introduction: biting midges (Diptera: Ceratopogonidae) are vectors of arboviral pathogens that primarily affect livestock represented by Schmallenberg virus (SBV), epizootic hemorrhagic disease virus (EHDV) and bluetongue virus (BTV). In Kenya, studies examining the bionomic features of including species diversity, blood-feeding habits, and association with viruses are limited.

Methods: Adult were surveyed using CDC light traps in two semi-arid ecologies, Baringo and Kajiado counties, in Kenya.

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Crimean-Congo haemorrhagic fever virus (CCHFV) is the causative agent of CCHF, a fatal viral haemorrhagic fever disease in humans. The maintenance of CCHFV in the ecosystem remains poorly understood. Certain tick species are considered as vectors and reservoirs of the virus.

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Dengue, caused by the dengue virus, is the most widespread arboviral infectious disease of public health significance globally. This review explores the communicative function of olfactory cues that mediate host-seeking, egg-laying, plant-feeding, and mating behaviors in and , two mosquito vectors that drive dengue virus transmission. has adapted to live in close association with humans, preferentially feeding on them and laying eggs in human-fabricated water containers and natural habitats.

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Insect-specific flaviviruses (ISFs), although not known to be pathogenic to humans and animals, can modulate the transmission of arboviruses by mosquitoes. In this study, we screened 6665 host-seeking, gravid and blood-fed mosquitoes for infection with flaviviruses and assessed the vertebrate hosts of the blood-fed mosquitoes sampled in Baringo and Kajiado counties; both dryland ecosystem counties in the Kenyan Rift Valley. Sequence fragments of two ISFs were detected.

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Hantaviruses are zoonotic rodent-borne viruses that are known to infect humans and cause various symptoms of disease, including hemorrhagic fever with renal and cardiopulmonary syndromes. They have a segmented single-stranded, enveloped, negative-sense RNA genome and are widely distributed. This study aimed to investigate the circulation of rodent-borne hantaviruses in peridomestic rodents and shrews in two semi-arid ecologies within the Kenyan Rift Valley.

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The tomato leafminer, is a destructive invasive pest of cultivated tomato and other Solanaceae plants, with yield losses of 80-100%. Mirid predators are key natural enemies of , but they also feed on host plants in the absence of their prey. Management of is a challenge due to its high biotic potential, resistance to many insecticides and the absence of sufficiently adapted auxiliary fauna in its new dispersion zones.

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Arboviruses are among emerging pathogens of public and veterinary health significance. However, in most of sub-Saharan Africa, their role in the aetiologies of diseases in farm animals is poorly described due to paucity of active surveillance and appropriate diagnosis. Here, we report the discovery of a previously unknown orbivirus in cattle collected in the Kenyan Rift Valley in 2020 and 2021.

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Background: Tephritid fruit flies are a major constraint to the global production of horticultural crops. In Africa, an array of native and alien invasive fruit fly species represents a key challenge to the horticultural industry. In an effort to develop a safer management tool for these pests, we previously identified glutathione (GSH) and glutamic acid (GA), as the host marking pheromones (HMPs) of Ceratitis cosyra and Ceratitis rosa, respectively.

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Ngari virus (NRIV) is a mosquito-borne reassortant orthobunyavirus that causes severe febrile illness and hemorrhagic fever in humans and small ruminants. Due to limited diagnostics and surveillance, NRIV has only been detected sporadically during Rift Valley fever virus outbreaks. Little is known on its interepidemic maintenance and geographic distribution.

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Article Synopsis
  • Infestation by insect pests like the Oriental fruit fly leads to major economic and food safety issues for growers and consumers.
  • Bactrocera dorsalis is a highly invasive pest that damages fruits and vegetables through its larvae, and early detection is crucial for managing these infestations.
  • A study identified unique odors from mangoes infested with B. dorsalis, differentiating them from non-infested and mechanically damaged mangoes, which could help improve detection methods in agriculture.
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Article Synopsis
  • Phleboviruses are emerging pathogens that are becoming more important for public health, but little is known about their link to ticks, especially in Africa.
  • Adult ticks from cattle, goats, and sheep were collected in two counties of Kenya and tested for phlebovirus infection, revealing distinct viral sequences related to tick-borne phleboviruses.
  • A total of thirty potential virus sequences were found in the ticks, indicating the presence of possibly three new viruses, highlighting the need for further research to understand their transmission and potential impact on animals and humans.
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Background: The selection of suitable host plants for oviposition is critical for herbivorous insects to maximise survival of their offspring. Olfaction plays an important role in this process. However, little is known about how olfaction shapes the interaction between the fall armyworm (Spodoptera frugiperda) and host plants.

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Aedes aegypti is the primary vector of dengue, chikungunya, and Zika viruses of medical importance. Behavioral and biological attributes contribute to its vectorial capacity. The mosquito domestic form, which resides outside Africa (Ae.

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Background: Thymol as a natural biological template can be modified chemically since the hydroxyl group makes it a candidate for structural modification. Thus, this study incorporated the triazole moiety on thymol and the chlorination of thymol moiety to help improve its biological potency.

Materials And Methods: A series of ten 1,2,3-triazole-thymol derivatives were synthesized from thymol, by a click reaction between O-propargyl terminal alkyne of thymol and its chlorothymol with benzyl azide and substituted benzyl azides.

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Trypanosomes are important global livestock and human pathogens of public health importance. Elucidating the chemical mechanisms of trypanosome-relevant host interactions can enhance the design and development of a novel, next-generation trypanosomosis diagnostics. However, it is unknown how trypanosome infection affects livestock volatile odors.

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