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Orubuloye OY, Mbewe NJ, Tchouassi DP, Yusuf AA, Pirk CWW, Torto B. An Overview of Tsetse Fly Repellents: Identification and Applications. J Chem Ecol 2024:10.1007/s10886-024-01527-5. [PMID: 38976099 DOI: 10.1007/s10886-024-01527-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Revised: 06/22/2024] [Accepted: 06/28/2024] [Indexed: 07/09/2024]
Abstract
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. Here, we present an overview of the identification of repellents and their development into control tools for tsetse flies. Both natural and synthetic repellents have been successfully tested in laboratory and field assays against specific tsetse fly species. Thus, these repellents presented as innovative mobile tools offer opportunities for their use in integrated disease management strategies.
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Affiliation(s)
- Olabimpe Y Orubuloye
- Department of Zoology and Entomology, University of Pretoria, Private Bag X20, Hatfield, 0028, Pretoria, South Africa.
| | - Njelembo J Mbewe
- Department of Zoology and Entomology, University of Pretoria, Private Bag X20, Hatfield, 0028, Pretoria, South Africa
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - David P Tchouassi
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772-00100, Nairobi, Kenya
| | - Abdullahi A Yusuf
- Department of Zoology and Entomology, University of Pretoria, Private Bag X20, Hatfield, 0028, Pretoria, South Africa
| | - Christian W W Pirk
- Department of Zoology and Entomology, University of Pretoria, Private Bag X20, Hatfield, 0028, Pretoria, South Africa
| | - Baldwyn Torto
- Department of Zoology and Entomology, University of Pretoria, Private Bag X20, Hatfield, 0028, Pretoria, South Africa
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772-00100, Nairobi, Kenya
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Feudjio Soffack S, Melachio Tanekou TT, Farikou O, Kame Ngasse GI, Tchami Mbagnia MC, Wondji M, Wondji CS, Abd-Alla AMM, Geiger A, Simo G, Njiokou F. The internal transcribed spacer 1 sequence polymorphism brings updates to tsetse species distribution in the northern Cameroon: Importance in planning efficient vector control. MEDICAL AND VETERINARY ENTOMOLOGY 2024; 38:216-226. [PMID: 38563591 DOI: 10.1111/mve.12717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Accepted: 02/02/2024] [Indexed: 04/04/2024]
Abstract
Vector control remains one of the best strategies to prevent the transmission of trypanosome infections in humans and livestock and, thus, a good way to achieve the elimination of human African trypanosomiasis and animal African trypanosomiasis. A key prerequisite for the success of any vector control strategy is the accurate identification and correct mapping of tsetse species. In this work, we updated the tsetse fly species identification and distribution in many geographical areas in Cameroon. Tsetse flies were captured from six localities in Cameroon, and their species were morphologically identified. Thereafter, DNA was extracted from legs of each tsetse fly and the length polymorphism of internal transcribed spacer-1 (ITS1) region of each fly was investigated using PCR. ITS1 DNA fragments of each tsetse species were sequenced. The sequences obtained were analysed and compared to those available in GenBank. This enabled to confirm/infirm results of the morphologic identification and then, to establish the phylogenetic relationships between tsetse species. Morphologic features allowed to clearly distinguish all the tsetse species captured in the South Region of Cameroon, that is, Glossina palpalis palpalis, G. pallicera, G. caliginea and G. nigrofusca. In the northern area, G. morsitans submorsitans could also be distinguished from G. palpalis palpalis, G. tachinoides and G. fuscipes, but these three later could not be distinguished with routine morphological characters. The ITS1 length polymorphism was high among most of the studied species and allowed to identify the following similar species with a single PCR, that is, G. palpalis palpalis with 241 or 242 bp and G. tachinoides with 221 or 222 bp, G. fuscipes with 236 or 237 bp. We also updated the old distribution of tsetse species in the areas assessed, highlighting the presence of G. palpalis palpalis instead of G. fuscipes in Mbakaou, or in sympatry with G. morsitans submorsitans in Dodeo (northern Cameroon). This study confirms the presence of G. palpalis palpalis in the Adamawa Region of Cameroon. It highlights the limits of using morphological criteria to differentiate some tsetse species. Molecular tools based on the polymorphism of ITS1 of tsetse flies can differentiate tsetse species through a simple PCR before downstream analyses or vector control planning.
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Affiliation(s)
- Steve Feudjio Soffack
- Laboratory of Parasitology and Ecology, Faculty of Science, University of Yaoundé I, Yaoundé, Cameroon
| | - Tito Tresor Melachio Tanekou
- Department of Microbiology and Parasitology, Faculty of Science, University of Bamenda, Bamenda, Cameroon
- Centre for Research in Infectious Diseases (CRID), Yaoundé, Cameroon
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Oumarou Farikou
- Faculty of Health Science, University of Bamenda, Bamenda, Cameroon
| | | | | | - Murielle Wondji
- Centre for Research in Infectious Diseases (CRID), Yaoundé, Cameroon
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Charles S Wondji
- Centre for Research in Infectious Diseases (CRID), Yaoundé, Cameroon
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Adly M M Abd-Alla
- Insect Pest Control Laboratory, Joint FAO/IAEA Centre of Nuclear Techniques in Food and Agriculture, Vienna, Austria
| | - Anne Geiger
- UMR177, Institut de Recherche pour le Développement (IRD)-CIRAD, Montpellier, France
| | - Gustave Simo
- Molecular Parasitology and Entomology Unit, Department of Biochemistry, Faculty of Science, University of Dschang, Dschang, Cameroon
| | - Flobert Njiokou
- Laboratory of Parasitology and Ecology, Faculty of Science, University of Yaoundé I, Yaoundé, Cameroon
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Chirwa KA, Francisco KR, Dube PS, Park H, Legoabe LJ, Teixeira TR, Caffrey CR, Beteck RM. Tractable Quinolone Hydrazides Exhibiting Sub-Micromolar and Broad Spectrum Antitrypanosomal Activities. ChemMedChem 2024; 19:e202300667. [PMID: 38326914 PMCID: PMC11076157 DOI: 10.1002/cmdc.202300667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Revised: 01/12/2024] [Accepted: 02/07/2024] [Indexed: 02/09/2024]
Abstract
Nagana and Human African Trypanosomiasis (HAT), caused by (sub)species of Trypanosoma, are diseases that impede human and animal health, and economic growth in Africa. The few drugs available have drawbacks including suboptimal efficacy, adverse effects, drug resistance, and difficult routes of administration. New drugs are needed. A series of 20 novel quinolone compounds with affordable synthetic routes was made and evaluated in vitro against Trypanosoma brucei and HEK293 cells. Of the 20 compounds, 12 had sub-micromolar potencies against the parasite (EC50 values=0.051-0.57 μM), and most were non-toxic to HEK293 cells (CC50 values>5 μM). Two of the most potent compounds presented sub-micromolar activities against other trypanosome (sub)species (T. cruzi and T. b. rhodesiense). Although aqueous solubility is poor, both compounds possess good logD values (2-3), and either robust or poor microsomal stability profiles. These varying attributes will be addressed in future reports.
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Affiliation(s)
- Kgothatso A Chirwa
- Centre of Excellence for Pharmaceutical Sciences, North-West University, Potchefstroom, 2520, South Africa
| | - Karol R Francisco
- Center for Discovery and Innovation in Parasitic Diseases, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Phelelisiwe S Dube
- Centre of Excellence for Pharmaceutical Sciences, North-West University, Potchefstroom, 2520, South Africa
| | - Hayoung Park
- Center for Discovery and Innovation in Parasitic Diseases, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Lesetja J Legoabe
- Centre of Excellence for Pharmaceutical Sciences, North-West University, Potchefstroom, 2520, South Africa
| | - Thaiz Rodrigues Teixeira
- Center for Discovery and Innovation in Parasitic Diseases, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Conor R Caffrey
- Center for Discovery and Innovation in Parasitic Diseases, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Richard M Beteck
- Centre of Excellence for Pharmaceutical Sciences, North-West University, Potchefstroom, 2520, South Africa
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Ahmed AD, Kebede IA, Gebremeskel HF, Beriso TE. Epidemiological study on cattle trypanosomiasis and its vectors distributions in the Gambella regional state, southwestern Ethiopia. Res Vet Sci 2024; 171:105227. [PMID: 38513458 DOI: 10.1016/j.rvsc.2024.105227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 03/01/2024] [Accepted: 03/10/2024] [Indexed: 03/23/2024]
Abstract
African animal trypanosomosis is a parasitic disease that causes significant economic losses in livestock due to anaemia, loss of condition, emaciation, and mortality. It is a key impediment to increased cattle output and productivity in Ethiopia. Cross-sectional entomological and parasitological studies were performed in the Gambella Region state of southwestern Ethiopia to estimate the prevalence of bovine trypanosomosis, apparent fly density, and potential risk factors. Blood samples were taken from 546 cattle for the parasitological study and analyzed using the buffy coat technique and stained with Giemsa. A total of 189 biconical (89) and NGU (100) traps were deployed in the specified districts for the entomological survey. The overall prevalence of trypanosomosis at the animal level was 5.5% (95% CI: 3.86-7.75). Trypanosoma vivax (50.0%), T. congolense (30.0%), T. brucei (20.0%), and no mixed trypanosome species were found. The prevalence of trypanosomosis was significantly (p < 0.05) affected by altitude, body score conditions, age, mean packed cell volume (PCV), and peasant associations, while sex and coat color had no significant effect. According to the entomological survey results, a total of 2303 flies were captured and identified as tsetse (Glossina pallidipes (5.3%)) and G. fuscipes fuscipes (3.3%) and other biting flies (Tabanus (60.1%) and Stomoxys (31.3%)). In the current study, the overall apparent density was 4.1 flies/trap/day. This study shows that trypanosomosis remains a significant cattle disease in the Gambella regional state even during the dry season. Thus, the findings support the necessity to improve vector and parasite control measures in the area.
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Mugatha SM, Ogutu JO, Piepho HP, Maitima JM. Bird species richness and diversity responses to land use change in the Lake Victoria Basin, Kenya. Sci Rep 2024; 14:1711. [PMID: 38243068 PMCID: PMC10798997 DOI: 10.1038/s41598-024-52107-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Accepted: 01/13/2024] [Indexed: 01/21/2024] Open
Abstract
The increasing demand for cultivated lands driven by human population growth, escalating consumption and activities, combined with the vast area of uncultivated land, highlight the pressing need to better understand the biodiversity conservation implications of land use change in Sub-Saharan Africa. Land use change alters natural wildlife habitats with fundamental consequences for biodiversity. Consequently, species richness and diversity typically decline as land use changes from natural to disturbed. We assess how richness and diversity of avian species, grouped into feeding guilds, responded to land use changes, primarily expansion of settlements and cultivation at three sites in the Lake Victoria Basin in western Kenya, following tsetse control interventions. Each site consisted of a matched pair of spatially adjacent natural/semi-natural and settled/cultivated landscapes. Significant changes occurred in bird species richness and diversity in the disturbed relative to the natural landscape. Disturbed areas had fewer guilds and all guilds in disturbed areas also occurred in natural areas. Guilds had significantly more species in natural than in disturbed areas. The insectivore/granivore and insectivore/wax feeder guilds occurred only in natural areas. Whilst species diversity was far lower, a few species of estrildid finches were more common in the disturbed landscapes and were often observed on the scrubby edges of modified habitats. In contrast, the natural and less disturbed wooded areas had relatively fewer estrildid species and were completely devoid of several other species. In aggregate, land use changes significantly reduced bird species richness and diversity on the disturbed landscapes regardless of their breeding range size or foraging style (migratory or non-migratory) and posed greater risks to non-migratory species. Accordingly, land use planning should integrate conservation principles that preserve salient habitat qualities required by different bird species, such as adequate patch size and habitat connectivity, conserve viable bird populations and restore degraded habitats to alleviate adverse impacts of land use change on avian species richness and diversity.
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Affiliation(s)
- Simon M Mugatha
- International Livestock Research Institute (ILRI), P.O. Box 30709, Nairobi, 00100, Kenya
| | - Joseph O Ogutu
- International Livestock Research Institute (ILRI), P.O. Box 30709, Nairobi, 00100, Kenya.
- Biostatistics Unit, Institute of Crop Science, University of Hohenheim, Fruwirthstrasse 23, 70599, Stuttgart, Germany.
| | - Hans-Peter Piepho
- Biostatistics Unit, Institute of Crop Science, University of Hohenheim, Fruwirthstrasse 23, 70599, Stuttgart, Germany
| | - Joseph M Maitima
- International Livestock Research Institute (ILRI), P.O. Box 30709, Nairobi, 00100, Kenya
- Ecodym Africa, P.O. Box 50901, Nairobi, 00200, Kenya
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Rascón-García K, Martínez-López B, Cecchi G, Scoglio C, Matovu E, Muhanguzi D. Prevalence of African animal trypanosomiasis among livestock and domestic animals in Uganda: a systematic review and meta-regression analysis from 1980 to 2022. Sci Rep 2023; 13:20337. [PMID: 37990067 PMCID: PMC10663568 DOI: 10.1038/s41598-023-47141-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 11/09/2023] [Indexed: 11/23/2023] Open
Abstract
African animal trypanosomiasis (AAT) is one of the major constraints to animal health and production in sub-Saharan Africa. To inform AAT control in Uganda and help advance along the progressive control pathway (PCP), we characterized AAT prevalence among eight host species in Uganda and explored factors that influence the prevalence variation between studies. We retrieved AAT prevalence publications (n = 2232) for Uganda (1980-2022) from five life sciences databases, focusing on studies specifying AAT detection methods, sample size, and the number of trypanosome-positive animals. Following PRISMA guidelines, we included 56 publications, and evaluated publication bias by the Luis Furuya-Kanamori (LFK) index. National AAT prevalence under DNA diagnostic methods for cattle, sheep and goats was 22.15%, 8.51% and 13.88%, respectively. Under DNA diagnostic methods, T. vivax was the most common Trypanosoma sp. in cattle (6.15%, 95% CI: 2.91-10.45) while T. brucei was most common among small ruminants (goats: 8.78%, 95% CI: 1.90-19.88, and sheep: 8.23%, 95% CI: 4.74-12.50, respectively). Northern and Eastern regions accounted for the highest AAT prevalence. Despite the limitations of this study (i.e., quality of reviewed studies, underrepresentation of districts/regions), we provide insights that could be used for better control of AAT in Uganda and identify knowledge gaps that need to be addressed to support the progressive control of AAT at country level and other regional endemic countries with similar AAT eco-epidemiology.
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Affiliation(s)
- Karla Rascón-García
- Department of Medicine & Epidemiology, School of Veterinary Medicine, Center for Animal Disease Modeling and Surveillance (CADMS), University of California, Davis, USA.
| | - Beatriz Martínez-López
- Department of Medicine & Epidemiology, School of Veterinary Medicine, Center for Animal Disease Modeling and Surveillance (CADMS), University of California, Davis, USA
| | - Giuliano Cecchi
- Animal Production and Health Division, Food and Agriculture Organization of the United Nations, Rome, Italy
| | - Caterina Scoglio
- Department of Electrical and Computer Engineering, Kansas State University, Manhattan, USA
| | - Enock Matovu
- Department of Biotechnical & Diagnostic Sciences (BDS), College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala, Uganda
| | - Dennis Muhanguzi
- Department of Bio-Molecular Resources and Bio-Laboratory Sciences, College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala, Uganda
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Clifford Astbury C, Lee KM, Mcleod R, Aguiar R, Atique A, Balolong M, Clarke J, Demeshko A, Labonté R, Ruckert A, Sibal P, Togño KC, Viens AM, Wiktorowicz M, Yambayamba MK, Yau A, Penney TL. Policies to prevent zoonotic spillover: a systematic scoping review of evaluative evidence. Global Health 2023; 19:82. [PMID: 37940941 PMCID: PMC10634115 DOI: 10.1186/s12992-023-00986-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Accepted: 11/01/2023] [Indexed: 11/10/2023] Open
Abstract
BACKGROUND Emerging infectious diseases of zoonotic origin present a critical threat to global population health. As accelerating globalisation makes epidemics and pandemics more difficult to contain, there is a need for effective preventive interventions that reduce the risk of zoonotic spillover events. Public policies can play a key role in preventing spillover events. The aim of this review is to identify and describe evaluations of public policies that target the determinants of zoonotic spillover. Our approach is informed by a One Health perspective, acknowledging the inter-connectedness of human, animal and environmental health. METHODS In this systematic scoping review, we searched Medline, SCOPUS, Web of Science and Global Health in May 2021 using search terms combining animal health and the animal-human interface, public policy, prevention and zoonoses. We screened titles and abstracts, extracted data and reported our process in line with PRISMA-ScR guidelines. We also searched relevant organisations' websites for evaluations published in the grey literature. All evaluations of public policies aiming to prevent zoonotic spillover events were eligible for inclusion. We summarised key data from each study, mapping policies along the spillover pathway. RESULTS Our review found 95 publications evaluating 111 policies. We identified 27 unique policy options including habitat protection; trade regulations; border control and quarantine procedures; farm and market biosecurity measures; public information campaigns; and vaccination programmes, as well as multi-component programmes. These were implemented by many sectors, highlighting the cross-sectoral nature of zoonotic spillover prevention. Reports emphasised the importance of surveillance data in both guiding prevention efforts and enabling policy evaluation, as well as the importance of industry and private sector actors in implementing many of these policies. Thoughtful engagement with stakeholders ranging from subsistence hunters and farmers to industrial animal agriculture operations is key for policy success in this area. CONCLUSION This review outlines the state of the evaluative evidence around policies to prevent zoonotic spillover in order to guide policy decision-making and focus research efforts. Since we found that most of the existing policy evaluations target 'downstream' determinants, additional research could focus on evaluating policies targeting 'upstream' determinants of zoonotic spillover, such as land use change, and policies impacting infection intensity and pathogen shedding in animal populations, such as those targeting animal welfare.
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Affiliation(s)
- Chloe Clifford Astbury
- School of Global Health, York University, Toronto, ON, Canada
- Dahdaleh Institute for Global Health Research, York University, Toronto, ON, Canada
- Global Strategy Lab, York University, Toronto, ON, Canada
| | - Kirsten M Lee
- School of Global Health, York University, Toronto, ON, Canada
- Dahdaleh Institute for Global Health Research, York University, Toronto, ON, Canada
| | - Ryan Mcleod
- School of Global Health, York University, Toronto, ON, Canada
| | - Raphael Aguiar
- Dahdaleh Institute for Global Health Research, York University, Toronto, ON, Canada
| | - Asma Atique
- School of Global Health, York University, Toronto, ON, Canada
| | - Marilen Balolong
- Applied Microbiology for Health and Environment Research Group, College of Arts and Sciences, University of the Philippines Manila, Manila, Philippines
| | - Janielle Clarke
- School of Global Health, York University, Toronto, ON, Canada
| | | | - Ronald Labonté
- School of Epidemiology and Public Health, University of Ottawa, Ottawa, ON, Canada
| | - Arne Ruckert
- School of Epidemiology and Public Health, University of Ottawa, Ottawa, ON, Canada
| | - Priyanka Sibal
- School of Health Policy and Management, York University, Toronto, ON, Canada
| | - Kathleen Chelsea Togño
- Applied Microbiology for Health and Environment Research Group, College of Arts and Sciences, University of the Philippines Manila, Manila, Philippines
| | - A M Viens
- School of Global Health, York University, Toronto, ON, Canada
- Global Strategy Lab, York University, Toronto, ON, Canada
| | - Mary Wiktorowicz
- School of Global Health, York University, Toronto, ON, Canada
- Dahdaleh Institute for Global Health Research, York University, Toronto, ON, Canada
| | - Marc K Yambayamba
- School of Public Health, University of Kinshasa, Kinshasa, Democratic Republic of Congo
| | - Amy Yau
- Department of Public Health, Environments and Society, London School of Hygiene & Tropical Medicine, London, UK
| | - Tarra L Penney
- School of Global Health, York University, Toronto, ON, Canada.
- Dahdaleh Institute for Global Health Research, York University, Toronto, ON, Canada.
- Global Strategy Lab, York University, Toronto, ON, Canada.
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Aminu S, Chechet GD, Alkhalil SS, Sobeh M, Daoud R, Simelane MB, Onyike E, Ibrahim MA. Therapeutic efficacy of β-sitosterol treatment on Trypanosoma congolense infection, anemia development, and trans-sialidase ( TconTS1) gene expression. Front Microbiol 2023; 14:1282257. [PMID: 37886075 PMCID: PMC10598747 DOI: 10.3389/fmicb.2023.1282257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Accepted: 09/13/2023] [Indexed: 10/28/2023] Open
Abstract
Background African animal trypanosomiasis hinders sustainable livestock productivity in sub-Saharan Africa. About 17 million infected cattle are treated with trypanocides annually but most of the drugs are associated with drawbacks, necessitating the search for a promising chemotherapeutic agent. Objectives In this study, the effects of β-sitosterol on Trypanosoma congolense infection were investigated along with its effect on the trans-sialidase gene expressions. Results Oral treatment with β-sitosterol at 15 and 30 mg/kg body weight (BW) for 14 days significantly (p < 0.05) reduced parasitemia and ameliorated the parasite-induced anemia. Also, the parasite-induced increase in serum urea level and renal histopathological damage scores in addition to renal hypertrophy was significantly (p < 0.05) reverted following treatment with 30 mg/kg BW β-sitosterol. The compound also significantly (p < 0.05) down-regulated the expression of TconTS1 but not TconTS2, TconTS3, and TconTS4. Correlation analysis between free serum sialic acid with the TconTS1 and TconTS2 gene variants revealed negative correlations in the β-sitosterol-treated groups although they were non-significant (p > 0.05) in the group treated with 15 mg/kg BW β-sitosterol. Similarly, a non-significant negative (p > 0.05) correlation between the biomolecule and the TconTS3 and TconTS4 gene variants was observed in the β-sitosterol-treated groups while positive correlations were observed in the infected untreated control group. Conclusion The observed effect of β-sitosterol on T. congolense infection could make the compound a possible template for the design of novel trypanocides.
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Affiliation(s)
- Suleiman Aminu
- Department of Biochemistry, Ahmadu Bello University, Zaria, Nigeria
- Chemical and Biochemical Sciences-Green Processing Engineering, Mohammed VI Polytechnic University, Ben Guerir, Morocco
| | - Gloria Dada Chechet
- Department of Biochemistry, Ahmadu Bello University, Zaria, Nigeria
- African Center of Excellence for Neglected Tropical Diseases and Forensic Biotechnology, Ahmadu Bello University, Zaria, Nigeria
| | - Samia S. Alkhalil
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Shaqra University, Alquwayiyah, Saudi Arabia
| | - Mansour Sobeh
- AgroBioSciences Program, College for Sustainable Agriculture and Environmental Science, Mohammed VI Polytechnic University, Ben Guerir, Morocco
| | - Rachid Daoud
- Chemical and Biochemical Sciences-Green Processing Engineering, Mohammed VI Polytechnic University, Ben Guerir, Morocco
| | | | - Elewechi Onyike
- Department of Biochemistry, Ahmadu Bello University, Zaria, Nigeria
| | - Mohammed Auwal Ibrahim
- Department of Biochemistry, Ahmadu Bello University, Zaria, Nigeria
- African Center of Excellence for Neglected Tropical Diseases and Forensic Biotechnology, Ahmadu Bello University, Zaria, Nigeria
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Iwaka C, Azando EVB, Houehanou TD, Kora S, Idrissou Y, Olounlade PA, Hounzangbe-Adote SM. Ethnoveterinary survey of trypanocidal medicinal plants of the beninese pharmacopoeia in the management of bovine trypanosomosis in North Benin (West Africa). Heliyon 2023; 9:e17697. [PMID: 37496927 PMCID: PMC10366400 DOI: 10.1016/j.heliyon.2023.e17697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Revised: 06/20/2023] [Accepted: 06/26/2023] [Indexed: 07/28/2023] Open
Abstract
Cattle breeding is of great socio-economic importance for Benin's cattle farmers in general and those of North Benin in particular. The objective of this study is to inventory the natural products of medicinal plants of the Beninese pharmacopoeia for the management of trypanosomes in cattle in North Benin. The methodology consisted of individual and semi-structured interviews with cattle farmers on the use of medicinal plants. A total of 360 cattle farmers were selected and interviewed in twelve villages in four municipalities (Tchaourou, N'dali, Bembèrèkè and Gogounou) in northern Benin. Different quantitative ethnobotanical indices were calculated to determine the level of use of plant species. The Relative Frequency of Citation (RFC), the Informant Consensus Factor (ICF = 0.918) and the Generic Coefficient (Rg = 1.04) were evaluated. The knowledge of medicinal plants was influenced by the level of education and the main activity of those who practiced animal husbandry. The results yielded 48 medicinal plants for veterinary use belonging to 46 genera and 28 families. The Leguminosae family (12.50%) was the most represented. The most cited plants with a RFC above 10% were K. senegalensis, P. africana, K. africana, M. inermis, S. latifolius, M. polyandra. The parts used were leaves (46.15%); barks (24.62%) and roots (15.38%). Decoction (53.23%), plundering (32.26%) and maceration (11.26%) were the main methods of preparation. The administration was mainly by oral route. The calculated indices show a high diversity of medicinal plants with trypanocidal properties in the control of cattle trypanosomosis in the Sudanese and Sudano-Guinean zones of northern Benin. Plant species with high citation and RFC values should be selected for comprehensive pharmacological and phytochemical research to validate this ethnomedical knowledge in the management of cattle trypanosomosis.
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Affiliation(s)
- Christophe Iwaka
- Laboratoire d’Ecologie, de Santé et de Production Animales (LESPA), Faculté d’Agronomie (FA), Université de Parakou (UP), 01 BP 123, Parakou, Benin
- Laboratoire d’Ecologie, de Botanique et de Biologie Végétale, Faculté d’Agronomie, Université de Parakou, 03 BP 125, Parakou, Benin
- Laboratoire d’Ethnopharmacologie et de Santé Animale, Faculté des Sciences Agronomiques, Université d’Abomey-Calavi, 01 BP 526, Cotonou, Benin
| | - Erick Virgile Bertrand Azando
- Laboratoire d’Ecologie, de Santé et de Production Animales (LESPA), Faculté d’Agronomie (FA), Université de Parakou (UP), 01 BP 123, Parakou, Benin
- Laboratoire de Biotechnologie et d’Amélioration Animale, Faculté des Sciences Agronomiques, Institut des Sciences Biomédicales Appliquées (ISBA), Université d’Abomey Calavi, 01 BP 526, Cotonou, Benin
- Laboratoire d’Ethnopharmacologie et de Santé Animale, Faculté des Sciences Agronomiques, Université d’Abomey-Calavi, 01 BP 526, Cotonou, Benin
| | - Thierry Dehouegnon Houehanou
- Laboratoire d’Ecologie, de Botanique et de Biologie Végétale, Faculté d’Agronomie, Université de Parakou, 03 BP 125, Parakou, Benin
- Laboratoire de Biomathématiques et d’Estimations Forestières, Faculté des Sciences Agronomiques, Université d’Abomey-Calavi, 04 BP 1525, Cotonou, Benin
| | - Sabi Kora
- Laboratoire d’Ecologie, de Santé et de Production Animales (LESPA), Faculté d’Agronomie (FA), Université de Parakou (UP), 01 BP 123, Parakou, Benin
| | - Yaya Idrissou
- Laboratoire d’Ecologie, de Santé et de Production Animales (LESPA), Faculté d’Agronomie (FA), Université de Parakou (UP), 01 BP 123, Parakou, Benin
| | - Pascal Abiodoun Olounlade
- Laboratoire de Biotechnologie et d’Amélioration Animale, Faculté des Sciences Agronomiques, Institut des Sciences Biomédicales Appliquées (ISBA), Université d’Abomey Calavi, 01 BP 526, Cotonou, Benin
- Laboratoire des Sciences Animale et Halieutique (LaSAH), Unité de Recherches Zootechnique et Système d’élevage, Ecole Doctorale des Sciences Agronomiques et de l’Eau, Université Nationale d’Agriculture, 01 BP 55, Porto Novo, Benin
- Laboratoire d’Ethnopharmacologie et de Santé Animale, Faculté des Sciences Agronomiques, Université d’Abomey-Calavi, 01 BP 526, Cotonou, Benin
| | - Sylvie Mawulé Hounzangbe-Adote
- Laboratoire d’Ethnopharmacologie et de Santé Animale, Faculté des Sciences Agronomiques, Université d’Abomey-Calavi, 01 BP 526, Cotonou, Benin
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10
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James SL, Quemada H, Benedict MQ, Dass B. Requirements for market entry of gene drive-modified mosquitoes for control of vector-borne diseases: analogies to other biologic and biotechnology products. Front Bioeng Biotechnol 2023; 11:1205865. [PMID: 37362219 PMCID: PMC10285705 DOI: 10.3389/fbioe.2023.1205865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 05/25/2023] [Indexed: 06/28/2023] Open
Abstract
Gene drive-modified mosquitoes (GDMMs) are proposed as new tools for control and elimination of malaria and other mosquito-borne diseases, and promising results have been observed from testing conducted in containment. Although still at an early stage of development, it is important to begin now to consider approval procedures and market entry strategies for the eventual implementation of GDMMs in the context of disease control programs, as these could impact future research plans. It is expected that, as for other types of new products, those seeking to bring GDMMs to market will be required to provide sufficient information to allow the regulator(s) to determine whether the product is safe and effective for its proposed use. There already has been much emphasis on developing requirements for the biosafety components of the "safe and effective" benchmark, largely concerned with their regulation as genetically modified organisms. Other potential approval requirements have received little attention, however. Although GDMMs are expected to be implemented primarily in the context of public health programs, any regulatory analogies to other public health products, such as pharmaceuticals, vaccines, or chemical pesticides, must take into account the characteristics of live mosquito products. Typical manufacturing standards related to product identity, potency or quality will need to be adapted to GDMMs. Valuable lessons can be drawn from the regulatory approval processes for other whole organism and genetically modified (GM) organism products. Supply chain requirements, such as scale of production, location and design of production facilities, and methods of distribution and delivery, will be dependent upon the characteristics of the particular GDMM product, the conditions of use, and the region to be served. Plans for fulfilling supply chain needs can build upon experience in the development of other live insect products for use in public health and agriculture. Implementation of GDMMs would benefit from additional research on enabling technologies for long-term storage of mosquito life stages, efficient mass production, and area-wide delivery of GDMMs. Early consideration of these practical requirements for market entry will help to mitigate downstream delays in the development of these promising new technologies.
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Affiliation(s)
- Stephanie L. James
- GeneConvene Global Collaborative, Foundation for the NIH, Bethesda, MD, United States
| | | | | | - Brinda Dass
- GeneConvene Global Collaborative, Foundation for the NIH, Bethesda, MD, United States
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11
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Osipov AV, Cheremnykh EG, Ziganshin RH, Starkov VG, Nguyen TTT, Nguyen KC, Le DT, Hoang AN, Tsetlin VI, Utkin YN. The Potassium Channel Blocker β-Bungarotoxin from the Krait Bungarus multicinctus Venom Manifests Antiprotozoal Activity. Biomedicines 2023; 11:biomedicines11041115. [PMID: 37189733 DOI: 10.3390/biomedicines11041115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Revised: 03/17/2023] [Accepted: 04/04/2023] [Indexed: 05/17/2023] Open
Abstract
Protozoal infections are a world-wide problem. The toxicity and somewhat low effectiveness of the existing drugs require the search for new ways of protozoa suppression. Snake venom contains structurally diverse components manifesting antiprotozoal activity; for example, those in cobra venom are cytotoxins. In this work, we aimed to characterize a novel antiprotozoal component(s) in the Bungarus multicinctus krait venom using the ciliate Tetrahymena pyriformis as a model organism. To determine the toxicity of the substances under study, surviving ciliates were registered automatically by an original BioLaT-3.2 instrument. The krait venom was separated by three-step liquid chromatography and the toxicity of the obtained fractions against T. pyriformis was analyzed. As a result, 21 kDa protein toxic to Tetrahymena was isolated and its amino acid sequence was determined by MALDI TOF MS and high-resolution mass spectrometry. It was found that antiprotozoal activity was manifested by β-bungarotoxin (β-Bgt) differing from the known toxins by two amino acid residues. Inactivation of β-Bgt phospholipolytic activity with p-bromophenacyl bromide did not change its antiprotozoal activity. Thus, this is the first demonstration of the antiprotozoal activity of β-Bgt, which is shown to be independent of its phospholipolytic activity.
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Affiliation(s)
- Alexey V Osipov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow 117997, Russia
| | | | - Rustam H Ziganshin
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow 117997, Russia
| | - Vladislav G Starkov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow 117997, Russia
| | | | - Khoa Cuu Nguyen
- Institute of Applied Materials Science, Vietnam Academy of Science and Technology, Ho Chi Minh City 700000, Vietnam
| | - Dung Tien Le
- Institute of Applied Materials Science, Vietnam Academy of Science and Technology, Ho Chi Minh City 700000, Vietnam
| | - Anh Ngoc Hoang
- Institute of Applied Materials Science, Vietnam Academy of Science and Technology, Ho Chi Minh City 700000, Vietnam
| | - Victor I Tsetlin
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow 117997, Russia
| | - Yuri N Utkin
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow 117997, Russia
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12
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James S, Santos M. The Promise and Challenge of Genetic Biocontrol Approaches for Malaria Elimination. Trop Med Infect Dis 2023; 8:201. [PMID: 37104327 PMCID: PMC10140850 DOI: 10.3390/tropicalmed8040201] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 03/15/2023] [Accepted: 03/23/2023] [Indexed: 04/03/2023] Open
Abstract
Malaria remains an ongoing public health challenge, with over 600,000 deaths in 2021, of which approximately 96% occurred in Africa. Despite concerted efforts, the goal of global malaria elimination has stalled in recent years. This has resulted in widespread calls for new control methods. Genetic biocontrol approaches, including those focused on gene-drive-modified mosquitoes (GDMMs), aim to prevent malaria transmission by either reducing the population size of malaria-transmitting mosquitoes or making the mosquitoes less competent to transmit the malaria parasite. The development of both strategies has advanced considerably in recent years, with successful field trials of several biocontrol methods employing live mosquito products and demonstration of the efficacy of GDMMs in insectary-based studies. Live mosquito biocontrol products aim to achieve area-wide control with characteristics that differ substantially from current insecticide-based vector control methods, resulting in some different considerations for approval and implementation. The successful field application of current biocontrol technologies against other pests provides evidence for the promise of these approaches and insights into the development pathway for new malaria control agents. The status of technical development as well as current thinking on the implementation requirements for genetic biocontrol approaches are reviewed, and remaining challenges for public health application in malaria prevention are discussed.
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Affiliation(s)
- Stephanie James
- Foundation for the National Institutes of Health, North Bethesda, MD 20852, USA
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13
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Muriithi BW, Menale K, Diiro GM, Okal MN, Masiga DK. Effect of use of tsetse repellant collar technology on the farm performance and household welfare of small-scale livestock farmers in Kenya. Food Secur 2023. [DOI: 10.1007/s12571-022-01342-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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14
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Mathewos M, Endale H, Fesseha H. Study on the prevalence and associated risk factors of bovine trypanosomiasis in Zaba Gazo Woreda, Southern Ethiopia. Res Vet Sci 2022; 152:53-57. [DOI: 10.1016/j.rvsc.2022.07.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Revised: 07/13/2022] [Accepted: 07/15/2022] [Indexed: 11/28/2022]
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15
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Clifford Astbury C, Lee KM, Aguiar R, Atique A, Balolong M, Clarke J, Labonte R, Ruckert A, Togño KC, Viens AM, Wiktorowicz M, Yau A, Penney TL. Policies to prevent zoonotic spillover: protocol for a systematic scoping review of evaluative evidence. BMJ Open 2022; 12:e058437. [PMID: 36379648 PMCID: PMC9668000 DOI: 10.1136/bmjopen-2021-058437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
INTRODUCTION The increasing incidence of pathogen transmission from animals to humans (zoonotic spillover events) has been attributed to behavioural practices and ecological and socioeconomic change. As these events sometimes involve pathogens with epidemic or pandemic potential, they pose a serious threat to population health. Public policies may play a key role in preventing these events. The aim of this review is to identify evaluations of public policies that target the determinants of zoonotic spillover, examining approaches taken to evaluation, choice of outcomes measures and evidence of effectiveness. Our approach to identifying and analysing this literature will be informed by a One Health lens, acknowledging the interconnectedness of human, animal and environmental health. METHODS AND ANALYSIS A systematic scoping review methodology will be used. To identify articles, we will search Medline, SCOPUS, Web of Science and Global Health in May 2021 using search terms combining animal health and the animal-human interface, public policy, prevention and zoonoses. We will screen titles and abstracts and extract data according to published guidelines for scoping reviews. All evaluations of public policies aiming to prevent zoonotic spillover events will be eligible for inclusion. We will summarise key data from each study, mapping policies along the spillover pathway and outlining the range of policies, approaches to evaluation and outcome measures. Review findings will provide a useful reference for researchers and practitioners, outlining the state of the evaluative evidence around policies to prevent zoonotic spillover. ETHICS AND DISSEMINATION Formal ethical approval is not required, because the study does not involve primary data collection. The findings of this study will be disseminated through a peer-reviewed publication, presentations and summaries for key stakeholders.
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Affiliation(s)
- Chloe Clifford Astbury
- School of Global Health, York University, Toronto, Ontario, Canada
- Dahdaleh Institute for Global Health Research, York University, Toronto, Ontario, Canada
| | - Kirsten M Lee
- School of Global Health, York University, Toronto, Ontario, Canada
- Dahdaleh Institute for Global Health Research, York University, Toronto, Ontario, Canada
| | - Raphael Aguiar
- Dahdaleh Institute for Global Health Research, York University, Toronto, Ontario, Canada
| | - Asma Atique
- School of Global Health, York University, Toronto, Ontario, Canada
| | | | - Janielle Clarke
- School of Global Health, York University, Toronto, Ontario, Canada
| | | | | | | | - A M Viens
- School of Global Health, York University, Toronto, Ontario, Canada
| | - M Wiktorowicz
- School of Global Health, York University, Toronto, Ontario, Canada
- Dahdaleh Institute for Global Health Research, York University, Toronto, Ontario, Canada
| | - Amy Yau
- London School of Hygiene & Tropical Medicine, London, UK
| | - Tarra L Penney
- School of Global Health, York University, Toronto, Ontario, Canada
- Dahdaleh Institute for Global Health Research, York University, Toronto, Ontario, Canada
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16
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Kizza D, Ocaido M, Mugisha A, Azuba R, Nalubwama S, Nalule S, Onyuth H, Musinguzi SP, Waiswa C. The economic cost of bovine trypanosomosis in pastoral and ago pastoral communities surrounding Murchision Falls National park, Buliisa district, Uganda. BMC Vet Res 2022; 18:372. [PMID: 36253776 PMCID: PMC9578198 DOI: 10.1186/s12917-022-03468-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Revised: 09/27/2022] [Accepted: 10/05/2022] [Indexed: 11/14/2022] Open
Abstract
Background: Animal diseases that are endemic like tsetse transmitted trypanosomosis cause the continuous expenditure of financial resources of livestock farmers and loss of productivity of livestock. Estimating the cost of controlling animal trypanosomosis can provide evidence for priority setting and targeting cost-effective control strategies. Methodology: A cross-sectional survey to estimate the economic cost of bovine trypanosomosis was conducted in cattle-keeping communities living around Murchision falls National Park, in Buliisa district Uganda. Data was collected on herd structure, the cost of treatment and control, prevalence of morbidity and mortality rates due to trypanosomosis, and salvage sales losses in cattle herds in the last year. Results: In this study, 55.4% (n = 87) of the households reported their cattle had been affected by trypanosomosis during the previous last year. There was a high economic cost of trypanosomosis (USD 653) per household in cattle-keeping communities in Buliisa district of which 83% and 9% were due to mortality and milk loss respectively/ High mortality loss was due to low investment in treatment. The study showed that prophylactic treatment 3 times a year of the whole herd of cattle using Samorin ® (Isometamidium chloride) at a cost of USD 110 could drastically reduce cattle mortality loss due to trypanosomosis due to trypanosomosis with a return on investment of USD 540 annually per herd. This could be coupled with strategic restricted insecticide spraying of cattle with deltamethrin products. Conclusion: The results show a high economic cost of trypanosomosis in cattle-keeping communities in Buliisa district, with cattle mortality contributing the largest proportion of the economic cost. The high mortality loss was due to low investment in treatment of sick cattle.
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Affiliation(s)
- Daniel Kizza
- Department of Livestock and Industrial Resources, College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, Kampala, Uganda.
| | - Michael Ocaido
- Department of Wildlife, Aquatic and Animal Resources, College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, Kampala, Uganda
| | - Anthony Mugisha
- Department of Livestock and Industrial Resources, College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, Kampala, Uganda
| | - Rose Azuba
- Department of Livestock and Industrial Resources, College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, Kampala, Uganda
| | - Sylvia Nalubwama
- Department of Livestock and Industrial Resources, College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, Kampala, Uganda
| | - Sarah Nalule
- Department of Wildlife, Aquatic and Animal Resources, College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, Kampala, Uganda
| | - Howard Onyuth
- Department of Wildlife, Aquatic and Animal Resources, College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, Kampala, Uganda
| | - Simon Peter Musinguzi
- Faculty of Agriculture Department of Agricultural Production, Kyambogo University, Kampala, Uganda
| | - Charles Waiswa
- Department of Veterinary Pharmacy, Clinical and Comparative Medicine, College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, Kampala, Uganda
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17
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Desquesnes M, Sazmand A, Gonzatti M, Boulangé A, Bossard G, Thévenon S, Gimonneau G, Truc P, Herder S, Ravel S, Sereno D, Waleckx E, Jamonneau V, Jacquiet P, Jittapalapong S, Berthier D, Solano P, Hébert L. Diagnosis of animal trypanosomoses: proper use of current tools and future prospects. Parasit Vectors 2022; 15:235. [PMID: 35761373 PMCID: PMC9238167 DOI: 10.1186/s13071-022-05352-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 06/05/2022] [Indexed: 12/24/2022] Open
Abstract
Reliable diagnostic tools are needed to choose the appropriate treatment and proper control measures for animal trypanosomoses, some of which are pathogenic. Trypanosoma cruzi, for example, is responsible for Chagas disease in Latin America. Similarly, pathogenic animal trypanosomoses of African origin (ATAO), including a variety of Trypanosoma species and subspecies, are currently found in Africa, Latin America and Asia. ATAO limit global livestock productivity and impact food security and the welfare of domestic animals. This review focusses on implementing previously reviewed diagnostic methods, in a complex epizootiological scenario, by critically assessing diagnostic results at the individual or herd level. In most cases, a single diagnostic method applied at a given time does not unequivocally identify the various parasitological and disease statuses of a host. These include “non-infected”, “asymptomatic carrier”, “sick infected”, “cured/not cured” and/or “multi-infected”. The diversity of hosts affected by these animal trypanosomoses and their vectors (or other routes of transmission) is such that integrative, diachronic approaches are needed that combine: (i) parasite detection, (ii) DNA, RNA or antigen detection and (iii) antibody detection, along with epizootiological information. The specificity of antibody detection tests is restricted to the genus or subgenus due to cross-reactivity with other Trypanosoma spp. and Trypanosomatidae, but sensitivity is high. The DNA-based methods implemented over the last three decades have yielded higher specificity and sensitivity for active infection detection in hosts and vectors. However, no single diagnostic method can detect all active infections and/or trypanosome species or subspecies. The proposed integrative approach will improve the prevention, surveillance and monitoring of animal trypanosomoses with the available diagnostic tools. However, further developments are required to address specific gaps in diagnostic methods and the sustainable control or elimination of these diseases.
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Affiliation(s)
- Marc Desquesnes
- UMR INTERTRYP, French Agricultural Research Centre for International Development (CIRAD), 31076, Toulouse, France.,INTERTRYP, IRD, CIRAD, University of Montpellier, Montpellier, France.,National Veterinary School of Toulouse (ENVT), 23 chemin des Capelles, 31000, Toulouse, France
| | - Alireza Sazmand
- Department of Pathobiology, Faculty of Veterinary Science, Bu-Ali Sina University, Hamedan, 6517658978, Iran.
| | - Marisa Gonzatti
- Department of Cell Biology, Simón Bolívar University, Caracas, 1080, Venezuela
| | - Alain Boulangé
- INTERTRYP, IRD, CIRAD, University of Montpellier, Montpellier, France.,UMR INTERTRYP, CIRAD, Bouaké, Côte d'Ivoire.,Pierre Richet Institute, National Public Health Institute, BP 1500, Bouaké, Côte d'Ivoire
| | - Géraldine Bossard
- INTERTRYP, IRD, CIRAD, University of Montpellier, Montpellier, France.,UMR INTERTRYP, CIRAD, 34398, Montpellier, France
| | - Sophie Thévenon
- INTERTRYP, IRD, CIRAD, University of Montpellier, Montpellier, France.,UMR INTERTRYP, CIRAD, 34398, Montpellier, France
| | - Geoffrey Gimonneau
- INTERTRYP, IRD, CIRAD, University of Montpellier, Montpellier, France.,UMR INTERTRYP, CIRAD , Dakar, Senegal.,National Laboratory for Livestock and Veterinary Research, Senegalese Institute on Agricultural Research (ISRA), BP 2057, Dakar, Hann, Senegal
| | - Philippe Truc
- IRD, UMR INTERTRYP, University of Montpellier, Montpellier, France
| | - Stéphane Herder
- IRD, UMR INTERTRYP, University of Montpellier, Montpellier, France
| | - Sophie Ravel
- IRD, UMR INTERTRYP, University of Montpellier, Montpellier, France
| | - Denis Sereno
- IRD, UMR INTERTRYP, University of Montpellier, Montpellier, France
| | - Etienne Waleckx
- IRD, UMR INTERTRYP, University of Montpellier, Montpellier, France.,Regional Research Centre Dr. Hideyo Noguchi, Autonomous University of Yucatán, Mérida, Yucatán, Mexico
| | | | - Philippe Jacquiet
- National Veterinary School of Toulouse (ENVT), 23 chemin des Capelles, 31000, Toulouse, France
| | | | - David Berthier
- INTERTRYP, IRD, CIRAD, University of Montpellier, Montpellier, France.,UMR INTERTRYP, CIRAD, 34398, Montpellier, France
| | - Philippe Solano
- IRD, UMR INTERTRYP, University of Montpellier, Montpellier, France
| | - Laurent Hébert
- Physiopathology & Epidemiology of Equine Diseases Unit (PhEED), Laboratory of Animal Health, Normandy Site, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Rd 675 Les Places, 14430, Goustranville, France
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18
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Aminu S, Ibrahim MA, Dada Chechet G, Onyike E. Chemotherapeutic potentials of β-ionone against Trypanosoma congolense infection: Inhibition of parasite proliferation, anemia development, trans-sialidase (TconTS3 and TconTS4) gene expressions, and phospholipase A 2. Chem Biol Drug Des 2022; 99:908-922. [PMID: 35353953 DOI: 10.1111/cbdd.14048] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 03/19/2022] [Accepted: 03/26/2022] [Indexed: 11/26/2022]
Abstract
Trypanosoma congolense is a pathogenic African animal trypanosome species causing devastating conditions leading to death of an infected host. The drawbacks of the existing trypanocidal drugs have led to the search for new drug candidates. In this study, β-ionone at 15 and 30 mg/kg body weight (BW) was orally administered to T. congolense infected rats for 14 days followed by an assessment of anemia, organ damages, and the expression of T. congolense trans-sialidase gene variants. A significant decrease in parasitemia (p < .05) was observed in the animals treated with 15 mg/kg BW β-ionone besides increased animal survival rate. A trypanosome-induced decrease in packed cell volume (PCV) and histopathological changes across tissues was significantly (p < .05) ameliorated following treatment with both doses of β-ionone. This is in addition to reversing the parasite-induced upsurge in free serum sialic acid (FSA) and expression of T. congolense trans-sialidase gene variants (TconTS1, TconTS3, and TconTS4). Correlation analysis revealed a positive correlation (p > .05) between FSA with the TconTS gene expressions. In addition, the compound inhibited partially purified T. congolense sialidase and phospholipase A2 via mixed inhibition pattern with inhibition binding constants of 25.325 and 4.550 µM, respectively, while molecular docking predicted binding energies of -5.6 kcal/mol for both enzymes. In conclusion, treatment with β-ionone suppressed T. congolense proliferation and protected the animals against some of the parasite-induced pathologies whilst the effect on anemia development might be due to inhibition of sialidase and PLA2 activities as well as the expression levels of TconTS3 and TconTS4.
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Affiliation(s)
- Suleiman Aminu
- Department of Biochemistry, Faculty of Life Sciences, Ahmadu Bello University, Zaria, Nigeria
| | - Mohammed Auwal Ibrahim
- Department of Biochemistry, Faculty of Life Sciences, Ahmadu Bello University, Zaria, Nigeria
| | - Gloria Dada Chechet
- Department of Biochemistry, Faculty of Life Sciences, Ahmadu Bello University, Zaria, Nigeria
| | - Elewechi Onyike
- Department of Biochemistry, Faculty of Life Sciences, Ahmadu Bello University, Zaria, Nigeria
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19
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Cheremnykh EG, Osipov AV, Starkov VG, Trang NTT, Khoa NC, Anh HN, Dung LT, Tsetlin VI, Utkin YN. Comparative Study of the Effect of Snake Venoms on the Growth of Ciliates Tetrahymena pyriformis: Identification of Venoms with High Antiprotozoal Activity. DOKL BIOCHEM BIOPHYS 2022; 503:98-103. [PMID: 35538287 DOI: 10.1134/s1607672922020041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 12/25/2021] [Accepted: 12/25/2021] [Indexed: 11/23/2022]
Abstract
To search for compounds with antiprotozoal activity, effects of snake venoms on the ciliates Tetrahymena pyriformis was studied. T. pyriformis from subkingdom of Protozoa, including the protozoal pathogens, was used as a model organism to select the venoms that are the most active against parasitic protozoans. Various concentrations of venoms were added to the cells, and the cells that survived after 24 h were counted. Among the six snake species from the Viperidae family, the venom of the viper Vipera berus, which completely killed the cells at 49 μg/mL, was the most active. Among four species from the Elapidae family, the previously studied cobra venoms containing cytotoxins with strong antiprotozoal activity as well as the venom of krait Bungarus multicinctus (10 μg/mL) were the most active. The venoms of the pit vipers and Nikolsky's viper did not show any activity at 12.5 mg/mL. Thus, the venoms of V. berus and B. multicinctus are promising for the isolation of new antiprotozoal compounds.
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Affiliation(s)
| | - A V Osipov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - V G Starkov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | | | - Nguyen Cuu Khoa
- Institute of Applied Materials Science, Vietnam Academy of Science and Technology, Ho Chi Minh, Vietnam
| | - Hoang Ngoc Anh
- Institute of Applied Materials Science, Vietnam Academy of Science and Technology, Ho Chi Minh, Vietnam
| | - Le Tien Dung
- Institute of Applied Materials Science, Vietnam Academy of Science and Technology, Ho Chi Minh, Vietnam
| | - V I Tsetlin
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Yu N Utkin
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia.
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Soudah B, Essodina T, Toï N, Balabadi D, Yao L, Martin Bienvenu S, Wendemanegde Ernest S. Assessment of α-Cypermethrin Pour-On Application and Diminazene Aceturate for Treating Trypanosome-Related Diseases Caused by Tsetse Flies on Cattle in Mô, Togo. JOURNAL OF MEDICAL ENTOMOLOGY 2022; 59:598-606. [PMID: 34935041 DOI: 10.1093/jme/tjab201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Indexed: 06/14/2023]
Abstract
The effects of tsetse-transmitted trypanosomosis control in high tsetse flies (Glossina spp.) challenge and trypanocidal drug resistance settings remain poorly understood in Togo owing to poor data coverage on the current disease impact. From March 2014 to November 2017, a database of zoo-sanitary surveys integrating the evolution of disease incidence and intervention coverage made it possible to quantify the apparent effects attributable to the control effort, focused on all sedentary cattle breeds in the 1,000 km² area of Mô in Togo. The strategy involved an initial phase with cross-sectional entomological and parasitological. Then, three times a year, 20% of the bovine animals of the study area received α-cypermethrin pour-on, and infected cattle with poor health (798 cattle in 2014 and 358 in 2017) were individually given diminazene aceturate at 7 mg/kg of body weight. The tsetse density in the area decreased significantly, from 1.78 ± 0.37 in March 2014 before the α-cypermethrin application to 0.48 ± 0.07 in February 2017. The α-cypermethrin pour-on application and diminazene aceturate treatment of cattle led to the largest reduction in disease incidence, from 28.1% in 2014 to 7.8% in 2017, an improvement in hematocrit from 24.27 ± 4.9% to 27.5 ± 4.6%, and a reduction in calf mortality from 15.9 ± 11% to 5.9%. Improved access to these interventions for different types of livestock and maintaining their effectiveness, despite high tsetse (Diptera: Glossinidae) challenges, should be the primary focus of control strategies in many areas of Togo.
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Affiliation(s)
- Boma Soudah
- Centre International de Recherche-Développement sur l'Elevage en zone Subhumide (CIRDES), rue 5-31 Avenu du Gouverneur Louveau, 01BP 454 Bobo-Dioulasso 01, Bobo Dioulasso, Burkina Faso/Institut Togolais de Recherche Agronomique (ITRA-Togo)
| | - Talaki Essodina
- Université de Lomé, Ecole Supérieure d'Agronomie (ESA), rue N°1, Bd Gnassingbe, 01 BP: 1515 Lomé, Togo
| | - N'feide Toï
- Institut Togolais de Recherche Agronomique (ITRA-Togo), rue N°1, Bd Gnassingbe, BP: 1163 Cacaveli, Lomé, Togo
| | - Dao Balabadi
- Institut Togolais de Recherche Agronomique (ITRA-Togo), rue N°1, Bd Gnassingbe, BP: 1163 Cacaveli, Lomé, Togo
| | - Lombo Yao
- Institut Togolais de Recherche Agronomique (ITRA-Togo), rue N°1, Bd Gnassingbe, BP: 1163 Cacaveli, Lomé, Togo
| | - Somda Martin Bienvenu
- Université Nazi Boni (UNB), Département de Sciences biologiques/UFR-ST (UNB), BP 1091 Bobo-Dioulasso, Burkina Faso
| | - Salou Wendemanegde Ernest
- Université Nazi Boni (UNB), Département de Sciences biologiques/UFR-ST (UNB), BP 1091 Bobo-Dioulasso, Burkina Faso
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Policy and Linkages in the Application of a One Health System for Reporting and Controlling African Trypanosomiasis and Other Zoonotic Diseases in Zambia. Pathogens 2021; 11:pathogens11010030. [PMID: 35055978 PMCID: PMC8781336 DOI: 10.3390/pathogens11010030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 12/24/2021] [Accepted: 12/26/2021] [Indexed: 12/02/2022] Open
Abstract
The capacity to detect, control and manage emerging and re-emerging zoonotic diseases in Africa has been limited by a lack of utilisation of available reporting structures and policies to support programmes at national and local levels. This study explored the impact of the Zambian government policies on animal and human disease reporting and management and on One Health opportunities. An in-depth review and analysis of strengths, weaknesses, opportunities, and threats in the existing policies and reporting structures in the departments responsible for Veterinary Services, Health, and Wildlife, was conducted. According to our findings, sub-optimal implementation of existing policies related to the control of zoonotic diseases was impacting disease reporting, and reporting structures play an important role in effective and sustainable reporting of zoonotic diseases. Further, the study explored capacities and strategies in trypanosomiasis control as a case study that could prompt effective adoption of a One Health approach, and as such, the study suggests measures that could help to assess the performance of a One Health system in the control of African trypanosomiasis and other zoonotic diseases.
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Abstract
Proteasomes are compartmentalized, ATP-dependent, N-terminal nucleophile hydrolases that play essentials roles in intracellular protein turnover. They are present in all 3 kingdoms. Pharmacological inhibition of proteasomes is detrimental to cell viability. Proteasome inhibitor rugs revolutionize the treatment of multiple myeloma. Proteasomes in pathogenic microbes such as Mycobacterium tuberculosis (Mtb), Plasmodium falciparum (Pf), and other parasites and worms have been validated as therapeutic targets. Starting with Mtb proteasome, efforts in developing inhibitors selective for microbial proteasomes have made great progress lately. In this review, we describe the strategies and pharmacophores that have been used in developing proteasome inhibitors with potency and selectivity that spare human proteasomes and highlight the development of clinical proteasome inhibitor candidates for treatment of leishmaniasis and Chagas disease. Finally, we discuss the future challenges and therapeutical potentials of the microbial proteasome inhibitors.
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Affiliation(s)
- Hao Zhang
- Department of Microbiology & Immunology, Weill Cornell Medicine, New York, New York, United States of America
| | - Gang Lin
- Department of Microbiology & Immunology, Weill Cornell Medicine, New York, New York, United States of America
- * E-mail:
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Kalayou S, Okal MN, Odhiambo PO, Mathenge K, Gamba DO, Kariuki E, McOdimba F, Masiga D. Prevalence of Trypanosome Species in Cattle Near Ruma National Park, Lambwe Valley, Kenya: An Update From the Historical Focus for African Trypanosomosis. Front Vet Sci 2021; 8:750169. [PMID: 34796227 PMCID: PMC8594777 DOI: 10.3389/fvets.2021.750169] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 10/04/2021] [Indexed: 11/13/2022] Open
Abstract
The effective control of diseases in areas shared with wildlife depends on the validity of the epidemiologic parameters that guide interventions. Epidemiologic data on animal trypanosomosis in Lambwe valley are decades old, and the recent suspected outbreaks of the disease in the valley necessitate the urgent bridging of this data gap. This cross-sectional study estimated the prevalence of bovine trypanosomosis, identified risk factors, and investigated the occurrence of species with zoonotic potential in Lambwe valley. The area is ~324 km2, of which 120 km2 is the Ruma National Park. Blood was sampled from the jugular and marginal ear veins of 952 zebu cattle between December 2018 and February 2019 and tested for trypanosomes using the Buffy Coat Technique (BCT) and PCR-High-Resolution Melting (HRM) analysis of the 18S RNA locus. Risk factors for the disease were determined using logistic regression. The overall trypanosome prevalence was 11.0% by BCT [95% confidence interval (CI): 9.0–13.0] and 27.9% by PCR-HRM (95% CI: 25.1–30.8). With PCR-HRM as a reference, four species of trypanosomes were detected at prevalences of 12.7% for T. congolense savannah (95% CI: 10.6–14.8), 7.7% for T. brucei brucei (CI: 6.0–9.4), 8.7% for T. vivax (CI: 6.9–10.5), and 1.3% for T. theileri (CI: 0.6–2.0). About 2.4% of cattle had mixed infections (CI: 1.4–3.41). No human-infective trypanosomes were found. Infections clustered across villages but were not associated with animal age, sex, herd size, and distance from the park. Approximately 85% of infections occurred within 2 km of the park. These findings add to evidence that previous interventions eliminated human trypanosomosis but not bovine trypanosomosis. Risk-tailored intervention within 2 km of Ruma Park, especially in the north and south ends, coupled with stringent screening with molecular tools, could significantly reduce bovine trypanosomosis.
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Affiliation(s)
- Shewit Kalayou
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | | | | | - Kawira Mathenge
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | | | - Edward Kariuki
- Veterinary and Capture Service Department, Kenya Wildlife Service, Nairobi, Kenya
| | - Francis McOdimba
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya.,Department of Biological Sciences, Faculty of Science, Egerton University, Nairobi, Kenya
| | - Daniel Masiga
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
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Gachoki S, Groen T, Vrieling A, Okal M, Skidmore A, Masiga D. Satellite-based modelling of potential tsetse (Glossina pallidipes) breeding and foraging sites using teneral and non-teneral fly occurrence data. Parasit Vectors 2021; 14:506. [PMID: 34583766 PMCID: PMC8479894 DOI: 10.1186/s13071-021-05017-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 09/14/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND African trypanosomiasis, which is mainly transmitted by tsetse flies (Glossina spp.), is a threat to public health and a significant hindrance to animal production. Tools that can reduce tsetse densities and interrupt disease transmission exist, but their large-scale deployment is limited by high implementation costs. This is in part limited by the absence of knowledge of breeding sites and dispersal data, and tools that can predict these in the absence of ground-truthing. METHODS In Kenya, tsetse collections were carried out in 261 randomized points within Shimba Hills National Reserve (SHNR) and villages up to 5 km from the reserve boundary between 2017 and 2019. Considering their limited dispersal rate, we used in situ observations of newly emerged flies that had not had a blood meal (teneral) as a proxy for active breeding locations. We fitted commonly used species distribution models linking teneral and non-teneral tsetse presence with satellite-derived vegetation cover type fractions, greenness, temperature, and soil texture and moisture indices separately for the wet and dry season. Model performance was assessed with area under curve (AUC) statistics, while the maximum sum of sensitivity and specificity was used to classify suitable breeding or foraging sites. RESULTS Glossina pallidipes flies were caught in 47% of the 261 traps, with teneral flies accounting for 37% of these traps. Fitted models were more accurate for the teneral flies (AUC = 0.83) as compared to the non-teneral (AUC = 0.73). The probability of teneral fly occurrence increased with woodland fractions but decreased with cropland fractions. During the wet season, the likelihood of teneral flies occurring decreased as silt content increased. Adult tsetse flies were less likely to be trapped in areas with average land surface temperatures below 24 °C. The models predicted that 63% of the potential tsetse breeding area was within the SHNR, but also indicated potential breeding pockets outside the reserve. CONCLUSION Modelling tsetse occurrence data disaggregated by life stages with time series of satellite-derived variables enabled the spatial characterization of potential breeding and foraging sites for G. pallidipes. Our models provide insight into tsetse bionomics and aid in characterising tsetse infestations and thus prioritizing control areas.
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Affiliation(s)
- Stella Gachoki
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
- Faculty of Geo-Information Science and Earth Observation (ITC), The University of Twente, Enschede, The Netherlands
| | - Thomas Groen
- Faculty of Geo-Information Science and Earth Observation (ITC), The University of Twente, Enschede, The Netherlands
| | - Anton Vrieling
- Faculty of Geo-Information Science and Earth Observation (ITC), The University of Twente, Enschede, The Netherlands
| | - Michael Okal
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - Andrew Skidmore
- Faculty of Geo-Information Science and Earth Observation (ITC), The University of Twente, Enschede, The Netherlands
- Macquarie University, Sydney, Australia
| | - Daniel Masiga
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
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25
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Abro Z, Kassie M, Muriithi B, Okal M, Masiga D, Wanda G, Gisèle O, Samuel A, Nguertoum E, Nina RA, Mansinsa P, Adam Y, Camara M, Olet P, Boucader D, Jamal S, Garba ARI, Ajakaiye JJ, Kinani JF, Hassan MA, Nonga H, Daffa J, Gidudu A, Chilongo K. The potential economic benefits of controlling trypanosomiasis using waterbuck repellent blend in sub-Saharan Africa. PLoS One 2021; 16:e0254558. [PMID: 34283848 PMCID: PMC8291668 DOI: 10.1371/journal.pone.0254558] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Accepted: 06/30/2021] [Indexed: 12/04/2022] Open
Abstract
Trypanosomiasis is a significant productivity-limiting livestock disease in sub-Saharan Africa, contributing to poverty and food insecurity. In this paper, we estimate the potential economic gains from adopting Waterbuck Repellent Blend (WRB). The WRB is a new technology that pushes trypanosomiasis-transmitting tsetse fly away from animals, improving animals’ health and increasing meat and milk productivity. We estimate the benefits of WRB on the production of meat and milk using the economic surplus approach. We obtained data from an expert elicitation survey, secondary and experimental sources. Our findings show that the adoption of WRB in 5 to 50% of the animal population would generate an economic surplus of US$ 78–869 million per annum for African 18 countries. The estimated benefit-cost ratio (9:1) further justifies an investment in WRB. The technology’s potential benefits are likely to be underestimated since our estimates did not include the indirect benefits of the technology adoption, such as the increase in the quantity and quality of animals’ draught power services and human and environmental health effects. These benefits suggest that investing in WRB can contribute to nutrition security and sustainable development goals.
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Affiliation(s)
- Zewdu Abro
- International Centre of Insect Physiology and Ecology (icipe), Addis Ababa, Ethiopia
- * E-mail:
| | - Menale Kassie
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - Beatrice Muriithi
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - Michael Okal
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - Daniel Masiga
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - Gift Wanda
- African Union, Coordinator of the Pan African Tsetse and Trypanosomiasis (T&T) Eradication Campaign (PATTEC), Addis Ababa, Ethiopia
| | - Ouedraogo Gisèle
- Country Coordinators of the Pan African Tsetse and Trypanosomiasis (T&T) Eradication Campaign (PATTEC) for Burkina Faso, Cameroon, Central Africa Republic, Congo, Democratic Republic of the Congo, Ghana, Guinea, Kenya, Mali, Mozambique, Niger, Nigeria, Rwanda, Sudan, Tanzania, Tanzania, Uganda, and Zambia, respectively
| | - Abah Samuel
- Country Coordinators of the Pan African Tsetse and Trypanosomiasis (T&T) Eradication Campaign (PATTEC) for Burkina Faso, Cameroon, Central Africa Republic, Congo, Democratic Republic of the Congo, Ghana, Guinea, Kenya, Mali, Mozambique, Niger, Nigeria, Rwanda, Sudan, Tanzania, Tanzania, Uganda, and Zambia, respectively
| | - Etienne Nguertoum
- Country Coordinators of the Pan African Tsetse and Trypanosomiasis (T&T) Eradication Campaign (PATTEC) for Burkina Faso, Cameroon, Central Africa Republic, Congo, Democratic Republic of the Congo, Ghana, Guinea, Kenya, Mali, Mozambique, Niger, Nigeria, Rwanda, Sudan, Tanzania, Tanzania, Uganda, and Zambia, respectively
| | - Rock Aimé Nina
- Country Coordinators of the Pan African Tsetse and Trypanosomiasis (T&T) Eradication Campaign (PATTEC) for Burkina Faso, Cameroon, Central Africa Republic, Congo, Democratic Republic of the Congo, Ghana, Guinea, Kenya, Mali, Mozambique, Niger, Nigeria, Rwanda, Sudan, Tanzania, Tanzania, Uganda, and Zambia, respectively
| | - Philémon Mansinsa
- Country Coordinators of the Pan African Tsetse and Trypanosomiasis (T&T) Eradication Campaign (PATTEC) for Burkina Faso, Cameroon, Central Africa Republic, Congo, Democratic Republic of the Congo, Ghana, Guinea, Kenya, Mali, Mozambique, Niger, Nigeria, Rwanda, Sudan, Tanzania, Tanzania, Uganda, and Zambia, respectively
| | - Yahaya Adam
- Country Coordinators of the Pan African Tsetse and Trypanosomiasis (T&T) Eradication Campaign (PATTEC) for Burkina Faso, Cameroon, Central Africa Republic, Congo, Democratic Republic of the Congo, Ghana, Guinea, Kenya, Mali, Mozambique, Niger, Nigeria, Rwanda, Sudan, Tanzania, Tanzania, Uganda, and Zambia, respectively
| | - Mamadou Camara
- Country Coordinators of the Pan African Tsetse and Trypanosomiasis (T&T) Eradication Campaign (PATTEC) for Burkina Faso, Cameroon, Central Africa Republic, Congo, Democratic Republic of the Congo, Ghana, Guinea, Kenya, Mali, Mozambique, Niger, Nigeria, Rwanda, Sudan, Tanzania, Tanzania, Uganda, and Zambia, respectively
| | - Pamela Olet
- Country Coordinators of the Pan African Tsetse and Trypanosomiasis (T&T) Eradication Campaign (PATTEC) for Burkina Faso, Cameroon, Central Africa Republic, Congo, Democratic Republic of the Congo, Ghana, Guinea, Kenya, Mali, Mozambique, Niger, Nigeria, Rwanda, Sudan, Tanzania, Tanzania, Uganda, and Zambia, respectively
| | - Diarra Boucader
- Country Coordinators of the Pan African Tsetse and Trypanosomiasis (T&T) Eradication Campaign (PATTEC) for Burkina Faso, Cameroon, Central Africa Republic, Congo, Democratic Republic of the Congo, Ghana, Guinea, Kenya, Mali, Mozambique, Niger, Nigeria, Rwanda, Sudan, Tanzania, Tanzania, Uganda, and Zambia, respectively
| | - Susana Jamal
- Country Coordinators of the Pan African Tsetse and Trypanosomiasis (T&T) Eradication Campaign (PATTEC) for Burkina Faso, Cameroon, Central Africa Republic, Congo, Democratic Republic of the Congo, Ghana, Guinea, Kenya, Mali, Mozambique, Niger, Nigeria, Rwanda, Sudan, Tanzania, Tanzania, Uganda, and Zambia, respectively
| | - Abdoul Razak Issa Garba
- Country Coordinators of the Pan African Tsetse and Trypanosomiasis (T&T) Eradication Campaign (PATTEC) for Burkina Faso, Cameroon, Central Africa Republic, Congo, Democratic Republic of the Congo, Ghana, Guinea, Kenya, Mali, Mozambique, Niger, Nigeria, Rwanda, Sudan, Tanzania, Tanzania, Uganda, and Zambia, respectively
| | - Joseph Joachim Ajakaiye
- Country Coordinators of the Pan African Tsetse and Trypanosomiasis (T&T) Eradication Campaign (PATTEC) for Burkina Faso, Cameroon, Central Africa Republic, Congo, Democratic Republic of the Congo, Ghana, Guinea, Kenya, Mali, Mozambique, Niger, Nigeria, Rwanda, Sudan, Tanzania, Tanzania, Uganda, and Zambia, respectively
| | - Jean Felix Kinani
- Country Coordinators of the Pan African Tsetse and Trypanosomiasis (T&T) Eradication Campaign (PATTEC) for Burkina Faso, Cameroon, Central Africa Republic, Congo, Democratic Republic of the Congo, Ghana, Guinea, Kenya, Mali, Mozambique, Niger, Nigeria, Rwanda, Sudan, Tanzania, Tanzania, Uganda, and Zambia, respectively
| | - Mohamed Adam Hassan
- Country Coordinators of the Pan African Tsetse and Trypanosomiasis (T&T) Eradication Campaign (PATTEC) for Burkina Faso, Cameroon, Central Africa Republic, Congo, Democratic Republic of the Congo, Ghana, Guinea, Kenya, Mali, Mozambique, Niger, Nigeria, Rwanda, Sudan, Tanzania, Tanzania, Uganda, and Zambia, respectively
| | - Hezron Nonga
- Country Coordinators of the Pan African Tsetse and Trypanosomiasis (T&T) Eradication Campaign (PATTEC) for Burkina Faso, Cameroon, Central Africa Republic, Congo, Democratic Republic of the Congo, Ghana, Guinea, Kenya, Mali, Mozambique, Niger, Nigeria, Rwanda, Sudan, Tanzania, Tanzania, Uganda, and Zambia, respectively
| | - Joyce Daffa
- Country Coordinators of the Pan African Tsetse and Trypanosomiasis (T&T) Eradication Campaign (PATTEC) for Burkina Faso, Cameroon, Central Africa Republic, Congo, Democratic Republic of the Congo, Ghana, Guinea, Kenya, Mali, Mozambique, Niger, Nigeria, Rwanda, Sudan, Tanzania, Tanzania, Uganda, and Zambia, respectively
| | - Ambrose Gidudu
- Country Coordinators of the Pan African Tsetse and Trypanosomiasis (T&T) Eradication Campaign (PATTEC) for Burkina Faso, Cameroon, Central Africa Republic, Congo, Democratic Republic of the Congo, Ghana, Guinea, Kenya, Mali, Mozambique, Niger, Nigeria, Rwanda, Sudan, Tanzania, Tanzania, Uganda, and Zambia, respectively
| | - Kalinga Chilongo
- Country Coordinators of the Pan African Tsetse and Trypanosomiasis (T&T) Eradication Campaign (PATTEC) for Burkina Faso, Cameroon, Central Africa Republic, Congo, Democratic Republic of the Congo, Ghana, Guinea, Kenya, Mali, Mozambique, Niger, Nigeria, Rwanda, Sudan, Tanzania, Tanzania, Uganda, and Zambia, respectively
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Richards S, Morrison LJ, Torr SJ, Barrett MP, Manangwa O, Mramba F, Auty H. Pharma to farmer: field challenges of optimizing trypanocide use in African animal trypanosomiasis. Trends Parasitol 2021; 37:831-843. [PMID: 33962879 DOI: 10.1016/j.pt.2021.04.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 04/05/2021] [Accepted: 04/08/2021] [Indexed: 01/07/2023]
Abstract
Trypanocides are a key control component of African animal trypanosomiasis (AAT) in tsetse-infested areas of sub-Saharan Africa. While farmers are dependent upon trypanocides, recent research highlights their inappropriate and ineffective use, problems with drug quality, and treatment failure. There are currently gaps in knowledge and investment in inexpensive AAT diagnostics, understanding of drug resistance, and the effective use of trypanocides in the field. Without this important knowledge it is difficult to develop best practice and policy for existing drugs or to inform development and use of new drugs. There needs to be better understanding of the drivers and behavioural practices around trypanocide use so that they can be incorporated into sustainable solutions needed for the development of effective control of AAT.
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Affiliation(s)
- Shauna Richards
- Institute of Biodiversity, Animal Health & Comparative Medicine, College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow, UK.
| | - Liam J Morrison
- Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, UK
| | - Steve J Torr
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Michael P Barrett
- Wellcome Centre for Integrative Parasitology, Institute of Infection, Inflammation & Immunity, College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow, UK
| | | | - Furaha Mramba
- Tanzania Veterinary Laboratory Agency, Dar Es Salaam, Tanzania
| | - Harriet Auty
- Institute of Biodiversity, Animal Health & Comparative Medicine, College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow, UK
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Meharenet B, Shitu D. Concurrent Infection of Fascioliasis andTrypanosomosis and Associated Risk Factors in Local Zebu Breed Cattle of Western Ethiopia. VETERINARY MEDICINE-RESEARCH AND REPORTS 2021; 12:15-22. [PMID: 33564623 PMCID: PMC7866923 DOI: 10.2147/vmrr.s285165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 01/11/2021] [Indexed: 11/23/2022]
Abstract
Background A cross-sectional study was conducted from late October 2016 to June 2017, with the primary objective of estimating and analyzing the concurrent occurrence of both fascioliasis and trypanosomosis infections and associated risk factors along the tsetse-infested Didessa river basin. Methods The methodology applied was based on stratified sampling for the parasitological study, with entomological and malacological surveys, including fly dissection. Results The result of variance-ratio testing between trypanosomosis and fascioliasis infections (mean prevalence 0.117±0.322 and 0.283±0.451, respectively), was statistically significant (P[F>f]=0), with higher observed fascioliasis infection (n=147, 28.27%). Severe anemia was observed in trypanosomosis infection, with mean packed cell volume of 19.57 (OR=0.71, P>|z|=0.000), and vast fascioliasis infections identified among cattle with medium and poor body condition in terms of weight (n=91 [32.73%] and n=38 [21.47%]). On entomological study, 578 (62.62%) and 345 (37.38%) female and male Glossina tachinoides fly species were cached, respectively, with overall mean flies/trap/day of 5.19 (n=923). Despite the prevalence of trypanosomosis in infected cattle, of 130 G. tachinoides flies dissected, only three were found to be positive for an infection rate of 2.31%. Malacological study identified three snail species known to maintain fascioliasis: Lymnea truncatula (n=28, 45.16%), Lymnea natalensis (n=23, 37.10%), and Biomphalaria (n=11, 17.74%). Concurrent infection with fascioliasis and trypanosomosis was mainly associated with the co-occurrence of their intermediate host snails and Glossina flies, respectively, with 4.42% (n=23) prevalence. Conclusion This study clearly demonstrated that the former parasite was highly associated with emaciation, whereas the second was responsible for anemia. In future,researchers should focus solely on estimating meat and milk production of local cattle to assess the economic impact of the study parasites.
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Affiliation(s)
- Behablom Meharenet
- National Institute for the Control and Eradication of Tsetse Fly and Trypanosomosis, Addis Ababa, Ethiopia
| | - Dessalew Shitu
- National Institute for the Control and Eradication of Tsetse Fly and Trypanosomosis, Addis Ababa, Ethiopia
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28
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Cecilia H, Arnoux S, Picault S, Dicko A, Seck MT, Sall B, Bassène M, Vreysen M, Pagabeleguem S, Bancé A, Bouyer J, Ezanno P. Dispersal in heterogeneous environments drives population dynamics and control of tsetse flies. Proc Biol Sci 2021; 288:20202810. [PMID: 33529565 PMCID: PMC7893214 DOI: 10.1098/rspb.2020.2810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Spatio-temporally heterogeneous environments may lead to unexpected population dynamics. Knowledge is needed on local properties favouring population resilience at large scale. For pathogen vectors, such as tsetse flies transmitting human and animal African trypanosomosis, this is crucial to target management strategies. We developed a mechanistic spatio-temporal model of the age-structured population dynamics of tsetse flies, parametrized with field and laboratory data. It accounts for density- and temperature-dependence. The studied environment is heterogeneous, fragmented and dispersal is suitability-driven. We confirmed that temperature and adult mortality have a strong impact on tsetse populations. When homogeneously increasing adult mortality, control was less effective and induced faster population recovery in the coldest and temperature-stable locations, creating refuges. To optimally select locations to control, we assessed the potential impact of treating them and their contribution to the whole population. This heterogeneous control induced a similar population decrease, with more dispersed individuals. Control efficacy was no longer related to temperature. Dispersal was responsible for refuges at the interface between controlled and uncontrolled zones, where resurgence after control was very high. The early identification of refuges, which could jeopardize control efforts, is crucial. We recommend baseline data collection to characterize the ecosystem before implementing any measures.
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Affiliation(s)
| | | | | | - Ahmadou Dicko
- Cirad, INRAE, ASTRE, University of Montpellier, Montpellier, France
| | - Momar Talla Seck
- Institut Sénégalais de Recherches Agricoles, Laboratoire National d'Elevage et de Recherches Vétérinaires, Dakar-Hann, Senegal
| | - Baba Sall
- Direction des Services vétérinaires, Ministère de l'Elevage et des Productions animales, Sphères ministérielles de Diamniadio, Bât. C, 3ème étage, Senegal
| | - Mireille Bassène
- Institut Sénégalais de Recherches Agricoles, Laboratoire National d'Elevage et de Recherches Vétérinaires, Dakar-Hann, Senegal
| | - Marc Vreysen
- Insect Pest Control Laboratory, Joint FAO/IAEA Programme of Nuclear Techniques in Food and Agriculture, 1400 Vienna, Austria
| | - Soumaïla Pagabeleguem
- Insectarium de Bobo-Dioulasso - Campagne d'Eradication des Tsé-tsé et Trypanosomoses (IBD-CETT), Bobo-Dioulasso 01, BP 1087, Burkina Faso.,Université de Dédougou (UDDG), BP 176, Burkina Faso
| | - Augustin Bancé
- Centre International de Recherche-Développement sur l'Elevage en Zone Subhumide (CIRDES), Bobo-Dioulasso 01 01 BP 454, Burkina Faso
| | - Jérémy Bouyer
- Cirad, INRAE, ASTRE, University of Montpellier, Montpellier, France.,Insect Pest Control Laboratory, Joint FAO/IAEA Programme of Nuclear Techniques in Food and Agriculture, 1400 Vienna, Austria.,UMR 'Interactions hôtes-vecteurs-parasites-environnement dans les maladies tropicales négligées dues aux trypanosomatides', Cirad, Montpellier, France
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Bacterial Symbionts of Tsetse Flies: Relationships and Functional Interactions Between Tsetse Flies and Their Symbionts. Results Probl Cell Differ 2021; 69:497-536. [PMID: 33263885 DOI: 10.1007/978-3-030-51849-3_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2023]
Abstract
Tsetse flies (Glossina spp.) act as the sole vectors of the African trypanosome species that cause Human African Trypanosomiasis (HAT or African Sleeping Sickness) and Nagana in animals. These flies have undergone a variety of specializations during their evolution including an exclusive diet consisting solely of vertebrate blood for both sexes as well as an obligate viviparous reproductive biology. Alongside these adaptations, Glossina species have developed intricate relationships with specific microbes ranging from mutualistic to parasitic. These relationships provide fundamental support required to sustain the specializations associated with tsetse's biology. This chapter provides an overview on the knowledge to date regarding the biology behind these relationships and focuses primarily on four bacterial species that are consistently associated with Glossina species. Here their interactions with the host are reviewed at the morphological, biochemical and genetic levels. This includes: the obligate symbiont Wigglesworthia, which is found in all tsetse species and is essential for nutritional supplementation to the blood-specific diet, immune system maturation and facilitation of viviparous reproduction; the commensal symbiont Sodalis, which is a frequently associated symbiont optimized for survival within the fly via nutritional adaptation, vertical transmission through mating and may alter vectorial capacity of Glossina for trypanosomes; the parasitic symbiont Wolbachia, which can manipulate Glossina via cytoplasmic incompatibility and shows unique interactions at the genetic level via horizontal transmission of its genetic material into the genome in two Glossina species; finally, knowledge on recently observed relations between Spiroplasma and Glossina is explored and potential interactions are discussed based on knowledge of interactions between this bacterial Genera and other insect species. These flies have a simple microbiome relative to that of other insects. However, these relationships are deep, well-studied and provide a window into the complexity and function of host/symbiont interactions in an important disease vector.
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Tsetse blood-meal sources, endosymbionts and trypanosome-associations in the Maasai Mara National Reserve, a wildlife-human-livestock interface. PLoS Negl Trop Dis 2021; 15:e0008267. [PMID: 33406097 PMCID: PMC7822626 DOI: 10.1371/journal.pntd.0008267] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 01/22/2021] [Accepted: 11/22/2020] [Indexed: 01/06/2023] Open
Abstract
African trypanosomiasis (AT) is a neglected disease of both humans and animals caused by Trypanosoma parasites, which are transmitted by obligate hematophagous tsetse flies (Glossina spp.). Knowledge on tsetse fly vertebrate hosts and the influence of tsetse endosymbionts on trypanosome presence, especially in wildlife-human-livestock interfaces, is limited. We identified tsetse species, their blood-meal sources, and correlations between endosymbionts and trypanosome presence in tsetse flies from the trypanosome-endemic Maasai Mara National Reserve (MMNR) in Kenya. Among 1167 tsetse flies (1136 Glossina pallidipes, 31 Glossina swynnertoni) collected from 10 sampling sites, 28 (2.4%) were positive by PCR for trypanosome DNA, most (17/28) being of Trypanosoma vivax species. Blood-meal analyses based on high-resolution melting analysis of vertebrate cytochrome c oxidase 1 and cytochrome b gene PCR products (n = 354) identified humans as the most common vertebrate host (37%), followed by hippopotamus (29.1%), African buffalo (26.3%), elephant (3.39%), and giraffe (0.84%). Flies positive for trypanosome DNA had fed on hippopotamus and buffalo. Tsetse flies were more likely to be positive for trypanosomes if they had the Sodalis glossinidius endosymbiont (P = 0.0002). These findings point to complex interactions of tsetse flies with trypanosomes, endosymbionts, and diverse vertebrate hosts in wildlife ecosystems such as in the MMNR, which should be considered in control programs. These interactions may contribute to the maintenance of tsetse populations and/or persistent circulation of African trypanosomes. Although the African buffalo is a key reservoir of AT, the higher proportion of hippopotamus blood-meals in flies with trypanosome DNA indicates that other wildlife species may be important in AT transmission. No trypanosomes associated with human disease were identified, but the high proportion of human blood-meals identified are indicative of human African trypanosomiasis risk. Our results add to existing data suggesting that Sodalis endosymbionts are associated with increased trypanosome presence in tsetse flies.
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Mayoke A, Ouma JO, Mireji PO, Omondi SF, Muya SM, Itoua A, Okoth SO, Bateta R. Population Structure and Migration Patterns of the Tsetse Fly Glossina fuscipes in Congo-Brazzaville. Am J Trop Med Hyg 2020; 104:917-927. [PMID: 33372648 PMCID: PMC7941806 DOI: 10.4269/ajtmh.20-0774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 11/17/2020] [Indexed: 11/07/2022] Open
Abstract
Tsetse flies of the palpalis group, particularly Glossina fuscipes, are the main vectors of human African trypanosomiasis or sleeping sickness in Congo-Brazzaville. They transmit the deadly human parasite, Trypanosoma brucei gambiense and other trypanosomes that cause animal trypanosomiasis. Knowledge on diversity, population structure, population size, and gene flow is a prerequisite for designing effective tsetse control strategies. There is limited published information on these parameters including migration patterns of G. fuscipes in Congo-Brazzaville. We genotyped 288 samples of G. fuscipes from Bomassa (BMSA), Bouemba (BEMB), and Talangai (TLG) locations at 10 microsatellite loci and determined levels of genetic diversity, differentiation, structuring, and gene flow among populations. We observed high genetic diversity in all three localities. Mean expected heterozygosity was 0.77 ± 0.04, and mean allelic richness was 11.2 ± 1.35. Deficiency of heterozygosity was observed in all populations with positive and significant F IS values (0.077-0.149). Structure analysis revealed three clusters with genetic admixtures, evidence of closely related but potentially different taxa within G. fuscipes. Genetic differentiation indices were low but significant (F ST = 0.049, P < 0.05), indicating ongoing gene flow countered with a stronger force of drift. We recorded significant migration from all the three populations, suggesting exchange of genetic information between and among locations. Ne estimates revealed high and infinite population sizes in BEMB and TLG. These critical factors should be considered when planning area-wide tsetse control interventions in the country to prevent resurgence of tsetse from relict populations and/or reinvasion of cleared habitats.
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Affiliation(s)
- Abraham Mayoke
- Department of Molecular Biology and Biotechnology, Pan African University Institute for Basic Sciences, Technology and Innovation, Nairobi, Kenya
- Kenya Forestry Research Institute, Nairobi, Kenya
- Biotechnology Research Institute, Kenya Agricultural and Livestock Research Organization, Kikuyu, Kenya
- Marien Ngouabi University, Brazzaville, Congo
| | - Johnson O. Ouma
- African Technical Research Centre, Vector Health International, Arusha, Tanzania
| | - Paul O. Mireji
- Biotechnology Research Institute, Kenya Agricultural and Livestock Research Organization, Kikuyu, Kenya
| | | | - Shadrack M. Muya
- School of Biological Sciences, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
| | - Andre Itoua
- Laboratoire de Parasitologie, Centre de Recherche Veterinaire et Zootechniques, Brazzaville, Congo
| | - Sylvance O. Okoth
- Biotechnology Research Institute, Kenya Agricultural and Livestock Research Organization, Kikuyu, Kenya
| | - Rosemary Bateta
- Biotechnology Research Institute, Kenya Agricultural and Livestock Research Organization, Kikuyu, Kenya
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Wachira BM, Kabaka JM, Mireji PO, Okoth SO, Ng'ang'a MM, Murilla GA, Hassanali A. Blending studies with selected waterbuck odor constituents or analogues in the development of a potent repellent blend against savannah tsetse. Acta Trop 2020; 211:105597. [PMID: 32592683 PMCID: PMC10895417 DOI: 10.1016/j.actatropica.2020.105597] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Revised: 06/23/2020] [Accepted: 06/23/2020] [Indexed: 11/23/2022]
Abstract
Previous comparison of the body odors of tsetse-refractory waterbuck and those of tsetse-attractive ox and buffalo showed that a blend of 15 EAG-active compounds specific to waterbuck, including C5-C10 straight chain carboxylic acid homologues, methyl ketones (C8-C12 straight chain homologues and geranyl acetone), phenols (guaiacol and carvacrol) and δ-octalactone, was repellent to tsetse. A blend of four components selected from each class of compounds (δ-octalactone, pentanoic acid, guaiacol, and geranylacetone) showed repellence that is comparable to that of the 15 components blend and can provide substantial protection to cattle (more than 80%) from tsetse bites and trypanosome infections. Structure-activity studies with the lactone and phenol analogues showed that δ-nonalactone and 4-methylguaiacol are significantly more repellent than δ-octalactone and guaiacol, respectively. In the present study, we compared the responses of Glossina pallidipes and Glossina morsitans to i) blends comprising of various combinations of the most active analogues from each class of compounds, and ii) a four-component blend of δ-nonalactone, heptanoic acid, 4-methylguaiacol and geranyl acetone in different ratios in a two-choice wind-tunnel, followed by a field study with G. pallidipes population in a completely randomized Latin Square Design set ups. In the wind tunnel experiments, the blend of the four compounds in 6:4:2:1 ratio was found to be significantly more repellent (94.53%) than that in 1:1:1:1 proportion and those in other ratios. G. m. morsitans also showed a similar pattern of results. In field experiments with G. pallidipes population, the 6:4:2:1 blend of the four compounds also gave similar results. The results lay down useful groundwork in the large-scale development of more effective 'push' and 'push-pull' control tactics of the tsetse flies.
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Affiliation(s)
- Benson M Wachira
- Department of Chemistry, School of Pure and Applied Sciences, Kenyatta University, P.O. Box 43844-00100, Nairobi, Kenya; Biotechnology Research Institute - Kenya Agricultural and Livestock Research Organization, P.O. Box 362-00902, Kikuyu, Kenya.
| | - Joy M Kabaka
- Department of Biochemistry and Biotechnology, School of Pure and Applied Sciences, Kenyatta University, P.O. Box 43844-00100, Nairobi, Kenya
| | - Paul O Mireji
- Biotechnology Research Institute - Kenya Agricultural and Livestock Research Organization, P.O. Box 362-00902, Kikuyu, Kenya; Centre for Geographic Medicine Research - Coast, Kenya Medical Research Institute, P.O. Box 230-80108, Kilifi, Kenya.
| | - Sylvance O Okoth
- Biotechnology Research Institute - Kenya Agricultural and Livestock Research Organization, P.O. Box 362-00902, Kikuyu, Kenya
| | - Margaret M Ng'ang'a
- Department of Chemistry, School of Pure and Applied Sciences, Kenyatta University, P.O. Box 43844-00100, Nairobi, Kenya
| | - Grace A Murilla
- Biotechnology Research Institute - Kenya Agricultural and Livestock Research Organization, P.O. Box 362-00902, Kikuyu, Kenya
| | - Ahmed Hassanali
- Department of Chemistry, School of Pure and Applied Sciences, Kenyatta University, P.O. Box 43844-00100, Nairobi, Kenya
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An African Canine Trypanosomosis Case Import: Is There a Possibility of Creating a Secondary Focus of Trypanosoma congolense Infection in France? Pathogens 2020; 9:pathogens9090709. [PMID: 32867247 PMCID: PMC7558263 DOI: 10.3390/pathogens9090709] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 08/24/2020] [Accepted: 08/26/2020] [Indexed: 11/25/2022] Open
Abstract
African animal trypanosomosis are parasitic diseases caused by several protozoa of the genus Trypanosoma, transmitted by hematophagous insects, essentially tsetse flies, but also, less frequently by Tabanidae and Stomoxidae. They are geolocated in a part of the continent and affect livestock animals and carnivores; dogs are especially sensitive to them. They do not seem to present a zoonotic risk. Despite the chemical prevention with trypanocides for French military working dogs on mission in Côte d’Ivoire, a fatal case induced by Trypanosoma congolense in France after returning from Abidjan raises the question of an imported secondary focus. The clinical case was developed and the causative agent was confirmed by microscopy and PCR methods. The three necessary pillars to create a secondary potential focus are present: the parasite introduction in a new territory, the presence and the propagation vectors, and their proximity with sensitive species.
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Marsela M, Hayashida K, Nakao R, Chatanga E, Gaithuma AK, Naoko K, Musaya J, Sugimoto C, Yamagishi J. Molecular identification of trypanosomes in cattle in Malawi using PCR methods and nanopore sequencing: epidemiological implications for the control of human and animal trypanosomiases. Parasite 2020; 27:46. [PMID: 32686644 PMCID: PMC7370688 DOI: 10.1051/parasite/2020043] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Accepted: 06/25/2020] [Indexed: 11/24/2022] Open
Abstract
This study aimed to identify trypanosomes infecting cattle in Malawi in order to understand the importance of cattle in the transmission dynamics of Human African Trypanosomiasis (HAT) and Animal African Trypanosomosis (AAT). A total of 446 DNA samples from cattle blood from three regions of Malawi were screened for African trypanosomes by ITS1 PCR. The obtained amplicons were sequenced using a portable next-generation sequencer, MinION, for validation. Comparison of the results from ITS1 PCR and MinION sequencing showed that combining the two methods provided more accurate species identification than ITS1 PCR alone. Further PCR screening targeting the serum resistance-associated (SRA) gene was conducted to detect Trypanosoma brucei rhodesiense. Trypanosoma congolense was the most prevalent Trypanosoma sp., which was found in Nkhotakota (10.8%; 20 of 185), followed by Kasungu (2.5%; 5 of 199). Of note, the prevalence of T. b. rhodesiense detected by SRA PCR was high in Kasungu and Nkhotakota showing 9.5% (19 of 199) and 2.7% (5 of 185), respectively. We report the presence of animal African trypanosomes and T. b. rhodesiense from cattle at the human-livestock-wildlife interface for the first time in Malawi. Our results confirmed that animal trypanosomes are important causes of anemia in cattle and that cattle are potential reservoirs for human African trypanosomiasis in Malawi.
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Affiliation(s)
- Megasari Marsela
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Division of Collaboration and Education, Research Center for Zoonosis Control, Hokkaido University Kita-20, Nishi-10, Kita-ku Sapporo 001-0020 Hokkaido Japan
| | - Kyoko Hayashida
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Division of Collaboration and Education, Research Center for Zoonosis Control, Hokkaido University Kita-20, Nishi-10, Kita-ku Sapporo 001-0020 Hokkaido Japan
| | - Ryo Nakao
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Laboratory of Parasitology, Veterinary Medicine Faculty, Hokkaido University Kita-18, Nishi-9, Kita-ku Sapporo 060-0818 Hokkaido Japan
| | - Elisha Chatanga
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Laboratory of Parasitology, Veterinary Medicine Faculty, Hokkaido University Kita-18, Nishi-9, Kita-ku Sapporo 060-0818 Hokkaido Japan
| | - Alex Kiarie Gaithuma
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Division of Collaboration and Education, Research Center for Zoonosis Control, Hokkaido University Kita-20, Nishi-10, Kita-ku Sapporo 001-0020 Hokkaido Japan
| | - Kawai Naoko
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Division of Collaboration and Education, Research Center for Zoonosis Control, Hokkaido University Kita-20, Nishi-10, Kita-ku Sapporo 001-0020 Hokkaido Japan
| | - Janelisa Musaya
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Department of Pathology, College of Medicine, University of Malawi P/Bag 360 Chichiri 30096 Blantyre 3 Malawi
| | - Chihiro Sugimoto
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Division of Collaboration and Education, Research Center for Zoonosis Control, Hokkaido University Kita-20, Nishi-10, Kita-ku Sapporo 001-0020 Hokkaido Japan
| | - Junya Yamagishi
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Division of Collaboration and Education, Research Center for Zoonosis Control, Hokkaido University Kita-20, Nishi-10, Kita-ku Sapporo 001-0020 Hokkaido Japan
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International Collaboration Unit, Research Center for Zoonosis Control, Hokkaido University Kita-20, Nishi-10, Kita-ku Sapporo 001-0020 Hokkaido Japan
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Mulenga GM, Henning L, Chilongo K, Mubamba C, Namangala B, Gummow B. Insights into the Control and Management of Human and Bovine African Trypanosomiasis in Zambia between 2009 and 2019-A Review. Trop Med Infect Dis 2020; 5:E115. [PMID: 32664551 PMCID: PMC7559803 DOI: 10.3390/tropicalmed5030115] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 06/18/2020] [Accepted: 07/08/2020] [Indexed: 12/02/2022] Open
Abstract
Tsetse transmitted trypanosomiasis is a fatal disease commonly known as Nagana in cattle and sleeping sickness in humans. The disease threatens food security and has severe economic impact in Africa including most parts of Zambia. The level of effectiveness of commonly used African trypanosomiasis control methods has been reported in several studies. However, there have been no review studies on African trypanosomiasis control and management conducted in the context of One Health. This paper therefore seeks to fill this knowledge gap. A review of studies that have been conducted on African trypanosomiasis in Zambia between 2009 and 2019, with a focus on the control and management of trypanosomiasis was conducted. A total of 2238 articles were screened, with application of the search engines PubMed, PubMed Central and One Search. Out of these articles, 18 matched the required criteria and constituted the basis for the paper. An in-depth analysis of the 18 articles was conducted to identify knowledge gaps and evidence for best practices. Findings from this review provide stakeholders and health workers with a basis for prioritisation of African trypanosomiasis as an important neglected disease in Zambia and for formulation of One Health strategies for better control and/or management of the disease.
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Affiliation(s)
- Gloria M. Mulenga
- Department of Veterinary Services, Kakumbi Tsetse and Trypanosomiasis Research Station, P.O Box 70, Mfuwe 10101, Zambia
- Ministry of Fisheries and Livestock, Department of Veterinary Services, Lusaka 10101, Zambia; (K.C.); (C.M.)
- College of Public Health Medical and Veterinary Services, James Cook University, Townsville, Queensland 4814, Australia; (L.H.); (B.G.)
| | - Lars Henning
- College of Public Health Medical and Veterinary Services, James Cook University, Townsville, Queensland 4814, Australia; (L.H.); (B.G.)
| | - Kalinga Chilongo
- Ministry of Fisheries and Livestock, Department of Veterinary Services, Lusaka 10101, Zambia; (K.C.); (C.M.)
| | - Chrisborn Mubamba
- Ministry of Fisheries and Livestock, Department of Veterinary Services, Lusaka 10101, Zambia; (K.C.); (C.M.)
| | - Boniface Namangala
- Institute of distance learning, The University of Zambia, Lusaka 10101, Zambia;
| | - Bruce Gummow
- College of Public Health Medical and Veterinary Services, James Cook University, Townsville, Queensland 4814, Australia; (L.H.); (B.G.)
- Faculty of Veterinary Science, University of Pretoria, 0028 Pretoria, South Africa
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Adeyemi CM, Conibear AC, Mutorwa MK, Nokalipa IC, Isaacs M, Mnkandhla D, Hoppe HC, Lobb KA, Klein R, Kaye PT. Synthesis and anti-parasitic activity of achiral N-benzylated phosphoramidic acid derivatives. Bioorg Chem 2020; 101:103947. [PMID: 32559578 DOI: 10.1016/j.bioorg.2020.103947] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 05/11/2020] [Accepted: 05/14/2020] [Indexed: 10/24/2022]
Abstract
Synthetic pathways have been developed to access a series of N-benzylated phosphoramidic acid derivatives as novel, achiral analogues of the established Plasmodium falciparum 1-deoxy-d-xylulose-5-phosphate reductase (PfDXR) enzyme inhibitor, FR900098. Bioassays of the targeted compounds and their synthetic precursors have revealed minimal antimalarial activity but encouraging anti-trypanosomal activity - in one case with an IC50 value of 5.4 µM against Trypanosoma brucei, the parasite responsible for Nagana (African cattle sleeping sickness). The results of relevant in silico modelling and docking studies undertaken in the design and evaluation of these compounds are discussed.
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Affiliation(s)
| | - Anne C Conibear
- Department of Chemistry, Rhodes University, Grahamstown 6140, South Africa
| | - Marius K Mutorwa
- Department of Chemistry, Rhodes University, Grahamstown 6140, South Africa
| | - Iviwe C Nokalipa
- Department of Chemistry, Rhodes University, Grahamstown 6140, South Africa
| | - Michelle Isaacs
- Centre for Chemico- and Biomedicinal Research, Rhodes University, Grahamstown 6140, South Africa
| | - Dumisani Mnkandhla
- Centre for Chemico- and Biomedicinal Research, Rhodes University, Grahamstown 6140, South Africa
| | - Heinrich C Hoppe
- Department of Biochemistry and Microbiolgy, Rhodes University, Grahamstown 6140, South Africa; Centre for Chemico- and Biomedicinal Research, Rhodes University, Grahamstown 6140, South Africa
| | - Kevin A Lobb
- Department of Chemistry, Rhodes University, Grahamstown 6140, South Africa; Centre for Chemico- and Biomedicinal Research, Rhodes University, Grahamstown 6140, South Africa
| | - Rosalyn Klein
- Department of Chemistry, Rhodes University, Grahamstown 6140, South Africa; Centre for Chemico- and Biomedicinal Research, Rhodes University, Grahamstown 6140, South Africa
| | - Perry T Kaye
- Department of Chemistry, Rhodes University, Grahamstown 6140, South Africa; Centre for Chemico- and Biomedicinal Research, Rhodes University, Grahamstown 6140, South Africa.
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Mweempwa C, Mbewe NJ, De Deken R. Wing length of tsetse caught by stationary and mobile sampling methods. Acta Trop 2020; 204:105333. [PMID: 31926912 DOI: 10.1016/j.actatropica.2020.105333] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 01/02/2020] [Accepted: 01/05/2020] [Indexed: 10/25/2022]
Abstract
INTRODUCTION A variety of techniques have been used to control tsetse with varying degrees of success. In a study on the population structure of Glossina fuscipes fuscipes that recovered after a previous vector control trial on two Kenyan islands, it was reported that the average fly size on the intervention islands was significantly smaller than on the none intervention islands and also compared to the size before the intervention. The conclusion was that vector control using tiny targets exerted size selection pressure on the population. The study recommended for further studies and suggested that this phenomenon could be among the reasons why targets used as a sole control method have rare reports of successful elimination of tsetse populations. Therefore, in this paper we report on a study of body size of tsetse flies caught in epsilon traps (as a stationary device) and black screen fly rounds (as a mobile trapping device). MATERIALS AND METHODS The study was carried out in eastern Zambia to test the hypothesis that the body size (measured as wing length) of G. m. morsitans males or females, captured by epsilon traps and fly rounds is the same. RESULTS A total of 1442 (489 females and 953 males) wing length measurements of G. m. morsitans were used in the analysis. It was established that tsetse flies caught by epsilon traps are on average larger than those caught by fly rounds. The likelihood of a large female or male fly being caught by traps, relative to a small one, significantly increased by 5.088 times (95% CI: 3.138-8.429) and by 2.563 times (95% CI: 1.584-4.148), respectively, p < 0.0001, compared with being caught by fly rounds. The hypothesis was rejected. CONCLUSION This study showed that epsilon traps capture significantly larger G. m. morsitans than fly rounds do. Therefore, further research is recommended to verify i) whether the predilection of traps to capture larger flies has an effect on the process of tsetse elimination when targets are used e.g. targets may take longer to reach elimination than if the predilection was not there, ii) whether different results can be obtained on ecogeographic distribution of different sizes of the species if fly rounds are used for sampling instead of epsilon traps. The results from such studies could influence the strategies used in future control operations.
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Ndeffo-Mbah ML, Pandey A, Atkins KE, Aksoy S, Galvani AP. The impact of vector migration on the effectiveness of strategies to control gambiense human African trypanosomiasis. PLoS Negl Trop Dis 2019; 13:e0007903. [PMID: 31805051 PMCID: PMC6894748 DOI: 10.1371/journal.pntd.0007903] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 11/04/2019] [Indexed: 02/06/2023] Open
Abstract
Background Several modeling studies have been undertaken to assess the feasibility of the WHO goal of eliminating gambiense human African trypanosomiasis (g-HAT) by 2030. However, these studies have generally overlooked the effect of vector migration on disease transmission and control. Here, we evaluated the impact of vector migration on the feasibility of interrupting transmission in different g-HAT foci. Methods We developed a g-HAT transmission model of a single tsetse population cluster that accounts for migration of tsetse fly into this population. We used a model calibration approach to constrain g-HAT incidence to ranges expected for high, moderate and low transmission settings, respectively. We used the model to evaluate the effectiveness of current intervention measures, including medical intervention through enhanced screening and treatment, and vector control, for interrupting g-HAT transmission in disease foci under each transmission setting. Results We showed that, in low transmission settings, under enhanced medical intervention alone, at least 70% treatment coverage is needed to interrupt g-HAT transmission within 10 years. In moderate transmission settings, a combination of medical intervention and a vector control measure with a daily tsetse mortality greater than 0.03 is required to achieve interruption of disease transmission within 10 years. In high transmission settings, interruption of disease transmission within 10 years requires a combination of at least 70% medical intervention coverage and at least 0.05 tsetse daily mortality rate from vector control. However, the probability of achieving elimination in high transmission settings decreases with an increased tsetse migration rate. Conclusion Our results suggest that the WHO 2030 goal of G-HAT elimination is, at least in theory, achievable. But the presence of tsetse migration may reduce the probability of interrupting g-HAT transmission in moderate and high transmission foci. Therefore, optimal vector control programs should incorporate monitoring and controlling of vector density in buffer areas around foci of g-HAT control efforts. Gambian human African trypanosomiasis (g-HAT), also known as sleeping sickness, is a vector-borne parasitic disease transmitted by tsetse flies. If untreated, g-HAT infection will usually result in death. Recently, the World Health Organization (WHO) has targeted g-HAT for elimination through achieving interruption of transmission by 2030. To help inform elimination efforts, mathematical models have been used to evaluate the feasibility of the WHO goals in different g-HAT transmission foci. However, these mathematical models have generally ignored the role that tsetse migration may have in the spread and reemergence of g-HAT. Using a mathematical model, we evaluate the impact of tsetse migration on the effectiveness of current intervention measures for achieving interruption of g-HAT transmission in different transmission foci. We consider different interventions such as enhanced screening and treatment and vector control. We show that vector control has a great potential for reducing transmission. Still, the presence and intensity of tsetse migration can undermine its effectiveness for interrupting disease transmission, especially in high transmission foci. Our results indicate the need of accounting for tsetse surveillance and migration data in designing vector control efforts for g-HAT elimination.
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Affiliation(s)
- Martial L. Ndeffo-Mbah
- Department of Veterinary Integrative Biosciences, Texas A&M College of Veterinary Medicine and Biomedical Sciences, College Station, TX, United States of America
- Department of Epidemiology and Biostatistics, Texas A&M School of Public Health, College Station, TX, United States of America
- * E-mail:
| | - Abhishek Pandey
- Center for Infectious Disease Modeling and Analysis, Yale School of Public Health, New Haven, CT, United States of America
- Department of Epidemiology and Microbial Diseases, Yale School of Public Health, New Haven, CT, United States of America
| | - Katherine E. Atkins
- Department of Infectious Disease Epidemiology, Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Centre for Mathematical Modelling of Infectious Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Centre for Global Health, The Usher Institute for Population Health Sciences and Informatics, Edinburgh Medical School, The University of Edinburgh, Edinburgh, United Kingdom
| | - Serap Aksoy
- Department of Epidemiology and Microbial Diseases, Yale School of Public Health, New Haven, CT, United States of America
| | - Alison P. Galvani
- Center for Infectious Disease Modeling and Analysis, Yale School of Public Health, New Haven, CT, United States of America
- Department of Epidemiology and Microbial Diseases, Yale School of Public Health, New Haven, CT, United States of America
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Berté D, De Meeûs T, Kaba D, Séré M, Djohan V, Courtin F, N'Djetchi Kassi M, Koffi M, Jamonneau V, Ta BTD, Solano P, N'Goran EK, Ravel S. Population genetics of Glossina palpalis palpalis in sleeping sickness foci of Côte d'Ivoire before and after vector control. INFECTION, GENETICS AND EVOLUTION : JOURNAL OF MOLECULAR EPIDEMIOLOGY AND EVOLUTIONARY GENETICS IN INFECTIOUS DISEASES 2019; 75:103963. [PMID: 31301424 PMCID: PMC6853165 DOI: 10.1016/j.meegid.2019.103963] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 07/08/2019] [Accepted: 07/09/2019] [Indexed: 10/26/2022]
Abstract
Glossina palpalis palpalis remains the major vector of sleeping sickness in Côte d'Ivoire. The disease is still active at low endemic levels in Bonon and Sinfra foci in the western-central part of the country. In this study, we investigated the impact of a control campaign on G. p. palpalis population structure in Bonon and Sinfra foci in order to adapt control strategies. Genetic variation at microsatellite loci was used to examine the population structure of different G. p. palpalis cohorts before and after control campaigns. Isolation by distance was observed in our sampling sites. Before control, effective population size was high (239 individuals) with dispersal at rather short distance (731 m per generation). We found some evidence that some of the flies captured after treatment come from surrounding sites, which increased the genetic variance. One Locus, GPCAG, displayed a 1000% increase of subdivision measure after control while other loci only exhibited a substantial increase in variance of subdivision. Our data suggested a possible trap avoidance behaviour in G. p. palpalis. It is important to take into account and better understand the possible reinvasion from neighboring sites and trap avoidance for the sake of sustainability of control campaigns effects.
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Affiliation(s)
- Djakaridja Berté
- Institut Pierre Richet/Institut National de Santé Publique, Bouaké, Côte d'Ivoire; Université Felix Houphouët-Boigny, Abidjan, Côte d'Ivoire
| | | | - Dramane Kaba
- Institut Pierre Richet/Institut National de Santé Publique, Bouaké, Côte d'Ivoire
| | - Modou Séré
- Université de Dédougou (UDDG), Dédougou, Burkina Faso
| | - Vincent Djohan
- Institut Pierre Richet/Institut National de Santé Publique, Bouaké, Côte d'Ivoire; Université Felix Houphouët-Boigny, Abidjan, Côte d'Ivoire
| | - Fabrice Courtin
- Intertryp, IRD, Cirad, Univ Montpellier, Montpellier, France
| | - Martial N'Djetchi Kassi
- Laboratoire des Interactions Hôte-Microorganisme-Environnement et Evolution, Unité de Formation et de Recherche Environnement, Université Jean Lorougnon Guédé, Daloa, Côte d'Ivoire
| | - Mathurin Koffi
- Laboratoire des Interactions Hôte-Microorganisme-Environnement et Evolution, Unité de Formation et de Recherche Environnement, Université Jean Lorougnon Guédé, Daloa, Côte d'Ivoire
| | | | - Bi Tra Dieudonné Ta
- Institut Pierre Richet/Institut National de Santé Publique, Bouaké, Côte d'Ivoire; Université Felix Houphouët-Boigny, Abidjan, Côte d'Ivoire
| | - Philippe Solano
- Intertryp, IRD, Cirad, Univ Montpellier, Montpellier, France
| | | | - Sophie Ravel
- Intertryp, IRD, Cirad, Univ Montpellier, Montpellier, France
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Paguem A, Abanda B, Ndjonka D, Weber JS, Ngomtcho SCH, Manchang KT, Adoulmoumini M, Eisenbarth A, Renz A, Kelm S, Achukwi MD. Widespread co-endemicity of Trypanosoma species infecting cattle in the Sudano-Sahelian and Guinea Savannah zones of Cameroon. BMC Vet Res 2019; 15:344. [PMID: 31619238 PMCID: PMC6796345 DOI: 10.1186/s12917-019-2111-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Accepted: 09/24/2019] [Indexed: 11/22/2022] Open
Abstract
Background African animal trypanosomosis remains the major constraint of livestock production and livelihood of pastoral communities in Cameroon. Despite several decades of vector and parasite control efforts, it has not been eradicated. Alternative and sustainable control strategies require a sound knowledge of the local species, strains and vectors. In the Sudano-Sahelian and Guinea Savannah of Cameroon the prevalence and genetic diversity of trypanosomes infecting cattle was investigated by microscopy of cattle blood buffy coat and molecular methods using generic primers targeting parts of the internal transcribed spacer 1 (ITS-1) and encoded glycosomal glyceraldehyde 3-phosphate dehydrogenase-gene (gGAPDH). Results A total of 1176 randomly chosen cattle from five divisions in the Sudano-Sahelian and Guinea Savannah of Cameroon were examined. The overall prevalence of trypanosomes by microscopy was 5.9% (56/953) in contrast to 53.2% (626/1176) when molecular tools were used. This indicated a limited sensitivity of microscopy in subclinical infections with frequently low parasitemia. Three trypanosome species were identified by light microscopy: T. vivax (2.3%), T. brucei (3.7%) and T. congolense (3.0%), whereas five were identified by PCR, namely T. grayi/T. theileri (30.8%), T. vivax (17.7%), T. brucei (14.5%) and T. congolense (5.1%). Unexpected cases of T. grayi (n = 4) and T. theileri (n = 26) were confirmed by sequencing. Phylogenetic analysis of the gGAPDH revealed the presence of T. vivax, clade A and T. vivax clade C, which were co-endemic in the Faro et Deo division. T. grayi/T. theileri were the predominant species infecting cattle in tsetse free areas. In contrast, T. vivax, T. brucei and T. congolense were more abundant in areas where the Glossina-vectors were present. Conclusions The abundance of pathogenic trypanosomes in tsetse infested areas is alarming and even more, the occurrence of T. vivax, T. brucei, T. congolense, T. theileri and T. grayi in tsetse-free areas implies that tsetse control alone is not sufficient to control trypanosomosis in livestock. To implement control measures that reduce the risk of spread in tsetse free areas, close monitoring using molecular tools and a thorough search for alternative vectors of trypanosomes is recommended.
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Affiliation(s)
- Archile Paguem
- Faculty of Science, University of Ngaoundéré, P.O. Box 454, Ngaoundéré, Cameroon.,Institute for Evolution and Ecology, Department of Comparative Zoology, University of Tübingen, Auf der Morgenstelle 28, 72076, Tübingen, Germany
| | - Babette Abanda
- Faculty of Science, University of Ngaoundéré, P.O. Box 454, Ngaoundéré, Cameroon.,Institute for Evolution and Ecology, Department of Comparative Zoology, University of Tübingen, Auf der Morgenstelle 28, 72076, Tübingen, Germany
| | - Dieudonné Ndjonka
- Faculty of Science, University of Ngaoundéré, P.O. Box 454, Ngaoundéré, Cameroon
| | - Judith Sophie Weber
- Centre for Biomolecular Interactions Bremen (CBIB), Faculty of Biology and Chemistry, University of Bremen, 28334, Bremen, Germany
| | - Sen Claudine Henriette Ngomtcho
- Faculty of Science, University of Ngaoundéré, P.O. Box 454, Ngaoundéré, Cameroon.,Ministry of public health, Yaoundé, Cameroon
| | - Kingsley Tanyi Manchang
- Institute of Agricultural Research for Development (IRAD), Wakwa, P.O. Box 65, Ngaoundéré, Cameroon
| | - Mamoudou Adoulmoumini
- XSchool of Veterinary Medicine and Sciences, Department of Parasitology, University of Ngaoundéré, P.O. Box 454, Ngaoundéré, Cameroon
| | - Albert Eisenbarth
- Institute for Evolution and Ecology, Department of Comparative Zoology, University of Tübingen, Auf der Morgenstelle 28, 72076, Tübingen, Germany.,Institute of Novel and Emerging Infectious Diseases, Friedrich Löffler Institut, Federal Research Institute for Animal Health, Südufer 10, 17493, Greifswald, Insel Riems, Germany
| | - Alfons Renz
- Institute for Evolution and Ecology, Department of Comparative Zoology, University of Tübingen, Auf der Morgenstelle 28, 72076, Tübingen, Germany
| | - Sørge Kelm
- Centre for Biomolecular Interactions Bremen (CBIB), Faculty of Biology and Chemistry, University of Bremen, 28334, Bremen, Germany
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Olaide OY, Tchouassi DP, Yusuf AA, Pirk CWW, Masiga DK, Saini RK, Torto B. Zebra skin odor repels the savannah tsetse fly, Glossina pallidipes (Diptera: Glossinidae). PLoS Negl Trop Dis 2019; 13:e0007460. [PMID: 31181060 PMCID: PMC6586361 DOI: 10.1371/journal.pntd.0007460] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Revised: 06/20/2019] [Accepted: 05/11/2019] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND African trypanosomosis, primarily transmitted by tsetse flies, remains a serious public health and economic challenge in sub-Saharan Africa. Interventions employing natural repellents from non-preferred hosts of tsetse flies represent a promising management approach. Although zebras have been identified as non-preferred hosts of tsetse flies, the basis for this repellency is poorly understood. We hypothesized that zebra skin odors contribute to their avoidance by tsetse flies. METHODOLOGY/PRINCIPAL FINDINGS We evaluated the effect of crude zebra skin odors on catches of wild savannah tsetse flies (Glossina pallidipes Austen, 1903) using unbaited Ngu traps compared to the traps baited with two known tsetse fly management chemicals; a repellent blend derived from waterbuck odor, WRC (comprising geranylacetone, guaiacol, pentanoic acid and δ-octalactone), and an attractant comprising cow urine and acetone, in a series of Latin square-designed experiments. Coupled gas chromatography-electroantennographic detection (GC/EAD) and GC-mass spectrometry (GC/MS) analyses of zebra skin odors identified seven electrophysiologically-active components; 6-methyl-5-hepten-2-one, acetophenone, geranylacetone, heptanal, octanal, nonanal and decanal, which were tested in blends and singly for repellency to tsetse flies when combined with Ngu traps baited with cow urine and acetone in field trials. The crude zebra skin odors and a seven-component blend of the EAD-active components, formulated in their natural ratio of occurrence in zebra skin odor, significantly reduced catches of G. pallidipesby 66.7% and 48.9% respectively, and compared favorably with the repellency of WRC (58.1%- 59.2%). Repellency of the seven-component blend was attributed to the presence of the three ketones 6-methyl-5-hepten-2-one, acetophenone and geranylacetone, which when in a blend caused a 62.7% reduction in trap catch of G. pallidipes. CONCLUSIONS/SIGNIFICANCE Our findings reveal fundamental insights into tsetse fly ecology and the allomonal effect of zebra skin odor, and potential integration of the three-component ketone blend into the management toolkit for tsetse and African trypanosomosis control.
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Affiliation(s)
- Olabimpe Y. Olaide
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
- Department of Zoology and Entomology, University of Pretoria, Hatfield, South Africa
- * E-mail: ,
| | - David P. Tchouassi
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - Abdullahi A. Yusuf
- Department of Zoology and Entomology, University of Pretoria, Hatfield, South Africa
| | - Christian W. W. Pirk
- Department of Zoology and Entomology, University of Pretoria, Hatfield, South Africa
| | - Daniel K. Masiga
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - Rajinder K. Saini
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - Baldwyn Torto
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
- Department of Zoology and Entomology, University of Pretoria, Hatfield, South Africa
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Meisner J, Barnabas RV, Rabinowitz PM. A mathematical model for evaluating the role of trypanocide treatment of cattle in the epidemiology and control of Trypanosoma brucei rhodesiense and T. b. gambiense sleeping sickness in Uganda. Parasite Epidemiol Control 2019; 5:e00106. [PMID: 31061906 PMCID: PMC6487357 DOI: 10.1016/j.parepi.2019.e00106] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 02/19/2019] [Accepted: 04/13/2019] [Indexed: 11/25/2022] Open
Abstract
Background Human and animal African trypanosomiases impose a large economic and health burden in their endemic regions. Large strides have been made in the control of human African trypanosomiasis (HAT), yet these efforts have largely focused on the non-zoonotic form of the disease. Using a mathematical model with a 10 year time horizon, we demonstrate the role of the cattle treatment with trypanocides in the epidemiology of zoonotic and non-zoonotic HAT in Uganda, and its potential implications on elimination and eradication of the disease. Methodology/principal findings We created two compartmental, deterministic models, each comprised of three sub-models: humans, the tsetse fly vector (Glossina fuscipes fuscipes), and cattle. We applied these models to two HAT foci in Uganda: the gambiense (chronic, non-zoonotic) form in the Northern Region, and the rhodesiense (acute, zoonotic) form in the Eastern Region. Parameters were derived from prior literature or assumed. In both foci we assumed G. fuscipes fuscipes expresses zoophilic biting behavior. With trypanocide treatment of cattle administered every 3 months, treatment in stage I (representing engagement in active or passive surveillance) had a larger impact on HAT burden than cattle treatment coverage. However increasing cattle treatment coverage allowed for further reduction in prevalence in both foci. Using these model parameters, our estimated R0 suggests humans cannot alone sustain the HAT epidemic in Uganda. Conclusions/significance Even in the absence of zoonotic transmission, loss of a preferred tsetse host species can affect HAT risk. Thus One Health strategies which integrate HAT and animal African trypanosomiasis control may improve the timeliness and sustainability of gHAT and rHAT elimination and eradication in Uganda. Furthermore, such strategies reduce the burden of a high-morbidity livestock disease of economic importance. The African trypanosomiases cause human and animal morbidity and mortality. Large-scale control efforts have reduced new human cases in recent decades. Elimination of the chronic form of the human disease has been targeted for 2020. Models suggest elimination requires control of non-human tsetse and trypanosome hosts.
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Affiliation(s)
- Julianne Meisner
- Department of Epidemiology, University of Washington, Seattle, WA, USA.,Center for One Health Research, University of Washington, Seattle, WA, USA
| | - Ruanne V Barnabas
- Department of Global Health, University of Washington, Seattle, WA, USA
| | - Peter M Rabinowitz
- Center for One Health Research, University of Washington, Seattle, WA, USA.,Department of Global Health, University of Washington, Seattle, WA, USA.,Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA
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Tchamdja E, Clausen PH, Kulo AE, Batawui K, Bauer B, Den Abbeele JV, Delespaux V, Hoppenheit A. How rational drug use reduces trypanosome infections in cattle in chemo-resistance hot-spot villages of northern Togo. Acta Trop 2019; 190:159-165. [PMID: 30465741 DOI: 10.1016/j.actatropica.2018.11.023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2018] [Revised: 11/18/2018] [Accepted: 11/18/2018] [Indexed: 11/26/2022]
Abstract
The study assessed an integrated trypanosomosis control strategy in drug-resistant hotspot villages of northern Togo. This strategy comprised (i) rational trypanocidal drug use in symptomatic cattle, (ii) vectors and ticks control by targeted bi-monthly insecticidal spraying of the lower body parts of cattle and (iii) strategic deworming with Albendazole in the beginning and the end of the rainy season. The program was implemented between June 2014 and October 2015 in four villages in northern Togo, which had been previously identified as drug resistant hotspots for diminazene diaceturate (DA) and isometamidium chloride (ISM). The integrated control strategy was implemented in eight cattle herds at risk of the disease from two villages. Twelve herds from two other villages served as controls where trypanosomosis management and deworming remained under control of the farmers. Trypanocidal drug use during the study period was recorded by the intervention team based on the farmers' reports and own observations. Cattle herds were followed-up for trypanosomosis symptoms which were recorded at 3 to 4-month intervals, while extensive trypanosome diagnostics and recording of the packed cell volume were done before and after the intervention. Intervention herds had a significantly lower risk of trypanosome infection with a risk ratio of 0.18 (95% CI: 0.04, 0.91; p = 0.03), but no significant effect on mean packed cell volume was observed. However, trypanocidal treatments per animal per year were lower in intervention herds compared to control herds (0.3 vs 5 for DA and 0.8 vs 2 for ISM). This study demonstrates that the implementation of an integrated best-bet strategy leads to a reduced trypanosome prevalence under lowered trypanocidal use.
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Hargrove J, English S, Torr SJ, Lord J, Haines LR, van Schalkwyk C, Patterson J, Vale G. Wing length and host location in tsetse (Glossina spp.): implications for control using stationary baits. Parasit Vectors 2019; 12:24. [PMID: 30635017 PMCID: PMC6329045 DOI: 10.1186/s13071-018-3274-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 12/19/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND It has been suggested that attempts to eradicate populations of tsetse (Glossina spp.) using stationary targets might fail because smaller, less mobile individuals are unlikely to be killed by the targets. If true, tsetse caught in stationary traps should be larger than those from mobile baits, which require less mobility on the part of the flies. RESULTS Sampling tsetse in the Zambezi Valley of Zimbabwe, we found that the number of tsetse caught from stationary traps, as a percent of total numbers from traps plus a mobile vehicle, was ~5% for male G. morsitans morsitans (mean wing length 5.830 mm; 95% CI: 5.800-5.859 mm) and ~10% for females (6.334 mm; 95% CI: 6.329-6.338 mm); for G. pallidipes the figures were ~50% for males (6.830 mm; 95% CI: 6.821-6.838 mm) and ~75% for females (7.303 mm, 95% CI: 7.302-7.305 mm). As expected, flies of the smaller species (and the smaller sex) were less likely to be captured using stationary, rather than mobile sampling devices. For flies of a given sex and species the situation was more complex. Multivariable analysis showed that, for females of both species, wing lengths changed with ovarian age and the month, year and method of capture. For G. pallidipes, there were statistically significant interactions between ovarian age and capture month, year and method. For G. m. morsitans, there was only a significant interaction between ovarian age and capture month. The effect of capture method was, however, small in absolute terms: for G. pallidipes and G. m. morsitans flies caught on the mobile vehicle had wings only 0.24 and 0.48% shorter, respectively, than flies caught in stationary traps. In summary, wing length in field samples of tsetse varies with ovarian age, capture month and year and, weakly, with capture method. Suggestions that a target-based operation against G. f. fuscipes in Kenya caused a shift towards a smaller, less mobile population of tsetse, unavailable to the targets, failed to account for factors other than capture method. CONCLUSIONS The results are consistent with the successful use of targets to eradicate populations of tsetse in Zimbabwe. Until further, more nuanced, studies are conducted, it is premature to conclude that targets alone could not, similarly, be used to eradicate G. f. fuscipes populations in Kenya.
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Affiliation(s)
- John Hargrove
- SACEMA, University of Stellenbosch, Stellenbosch, South Africa.
| | - Sinead English
- School of Biological Sciences, University of Bristol, Bristol, UK
| | | | - Jennifer Lord
- Liverpool School of Tropical Medicine, Liverpool, UK
| | | | | | | | - Glyn Vale
- SACEMA, University of Stellenbosch, Stellenbosch, South Africa.,Natural Resources Institute, University of Greenwich, London, UK
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Waha K, van Wijk MT, Fritz S, See L, Thornton PK, Wichern J, Herrero M. Agricultural diversification as an important strategy for achieving food security in Africa. GLOBAL CHANGE BIOLOGY 2018; 24:3390-3400. [PMID: 29604153 PMCID: PMC6055696 DOI: 10.1111/gcb.14158] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 02/19/2018] [Accepted: 03/10/2018] [Indexed: 05/20/2023]
Abstract
Farmers in Africa have long adapted to climatic and other risks by diversifying their farming activities. Using a multi-scale approach, we explore the relationship between farming diversity and food security and the diversification potential of African agriculture and its limits on the household and continental scale. On the household scale, we use agricultural surveys from more than 28,000 households located in 18 African countries. In a next step, we use the relationship between rainfall, rainfall variability, and farming diversity to determine the available diversification options for farmers on the continental scale. On the household scale, we show that households with greater farming diversity are more successful in meeting their consumption needs, but only up to a certain level of diversity per ha cropland and more often if food can be purchased from off-farm income or income from farm sales. More diverse farming systems can contribute to household food security; however, the relationship is influenced by other factors, for example, the market orientation of a household, livestock ownership, nonagricultural employment opportunities, and available land resources. On the continental scale, the greatest opportunities for diversification of food crops, cash crops, and livestock are located in areas with 500-1,000 mm annual rainfall and 17%-22% rainfall variability. Forty-three percent of the African cropland lacks these opportunities at present which may hamper the ability of agricultural systems to respond to climate change. While sustainable intensification practices that increase yields have received most attention to date, our study suggests that a shift in the research and policy paradigm toward agricultural diversification options may be necessary.
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Affiliation(s)
| | - Mark T. van Wijk
- Livestock Systems and the EnvironmentInternational Livestock Research Institute (ILRI)NairobiKenya
| | - Steffen Fritz
- International Institute for Applied Systems Analysis (IIASA)LaxenburgAustria
| | - Linda See
- International Institute for Applied Systems Analysis (IIASA)LaxenburgAustria
| | - Philip K. Thornton
- CSIRO Agriculture & FoodSt LuciaQLDAustralia
- CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS), ILRINairobiKenya
| | - Jannike Wichern
- Plant Production SystemsWageningen University & ResearchWageningenthe Netherlands
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Meyer A, Holt HR, Oumarou F, Chilongo K, Gilbert W, Fauron A, Mumba C, Guitian J. Integrated cost-benefit analysis of tsetse control and herd productivity to inform control programs for animal African trypanosomiasis. Parasit Vectors 2018. [PMID: 29514668 PMCID: PMC5842553 DOI: 10.1186/s13071-018-2679-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Background Animal African trypanosomiasis (AAT) and its tsetse vector are responsible for annual losses estimated in billions of US dollars ($). Recent years have seen the implementation of a series of multinational interventions. However, actors of AAT control face complex resource allocation decisions due to the geographical range of AAT, diversity of ecological and livestock systems, and range of control methods available. Methods The study presented here integrates an existing tsetse abundance model with a bio-economic herd model that captures local production characteristics as well as heterogeneities in AAT incidence and breed. These models were used to predict the impact of tsetse elimination on the net value of cattle production in the districts of Mambwe, in Zambia, and Faro et Déo in Cameroon. The net value of cattle production under the current situation was used as a baseline, and compared with alternative publicly funded control programmes. In Zambia, the current baseline is AAT control implemented privately by cattle owners (Scenario Z0). In Cameroon, the baseline (Scenario C0) is a small-scale publicly funded tsetse control programme and privately funded control at farm level. The model was run for 10 years, using a discount rate of 5%. Results Compared to Scenario C0, benefit-cost ratios (BCR) of 4.5 (4.4–4.7) for Scenario C1 (tsetse suppression using insecticide treatment of cattle (ITC) and traps + maintenance with ITC barrier), and 3.8 (3.6–4.0) for Scenario C2 (tsetse suppression using ITC and traps + maintenance with barrier of targets), were estimated in Cameroon. For Zambia, the benefit-cost ratio calculated for Scenarios Z1 (targets, ITC barrier), Z2 (targets, barrier traps), Z3 (aerial spraying, ITC barrier), and Z4 (aerial spraying, barrier traps) were 2.3 (1.8 - 2.7), 2.0 (1.6-2.4), 2.8 (2.3–3.3) and 2.5 (2.0–2.9), respectively. Sensitivity analysis showed that the profitability of the projects is relatively resistant to variations in the costs of the interventions and their technical efficiency. Conclusions It is envisioned that the methodologies presented here will be useful for the evaluation and design of existing and future control programmes, ensuring they have tangible benefits in the communities they are targeting. Electronic supplementary material The online version of this article (10.1186/s13071-018-2679-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Anne Meyer
- Department of Pathobiology and Population Sciences, Royal Veterinary College, Hatfield, UK
| | - Hannah R Holt
- Department of Pathobiology and Population Sciences, Royal Veterinary College, Hatfield, UK.
| | - Farikou Oumarou
- Mission Spéciale d'Eradication des Glossines, Ngaoundéré, Cameroon
| | - Kalinga Chilongo
- Department of Veterinary Services, Tsetse and Trypanosomiasis Control Unit, Ministry of Fisheries and Livestock, Lusaka, Zambia
| | - William Gilbert
- Department of Pathobiology and Population Sciences, Royal Veterinary College, Hatfield, UK
| | - Albane Fauron
- Department of Pathobiology and Population Sciences, Royal Veterinary College, Hatfield, UK
| | - Chisoni Mumba
- Department of Disease Control, School of Veterinary Medicine, University of Zambia, P.O. Box 32379, Lusaka, Zambia
| | - Javier Guitian
- Department of Pathobiology and Population Sciences, Royal Veterinary College, Hatfield, UK
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Mbewe NJ, Saini RK, Torto B, Irungu J, Yusuf AA, Pirk C. Effects of vector control on the population structure of tsetse (Glossina fuscipes fuscipes) in western Kenya. Acta Trop 2018; 179:1-9. [PMID: 29248414 DOI: 10.1016/j.actatropica.2017.12.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 12/11/2017] [Accepted: 12/11/2017] [Indexed: 10/18/2022]
Abstract
Displacement rates of tsetse affect performance of targets during vector control. Fly size, one of the indicators of population structure usually obtained from wing measurement, is among the determinants of displacement rates. Although recovery of tsetse in previous intervention areas has been widely reported, the population structure of tsetse that recover is rarely evaluated despite being associated with displacements rates. Previously, intervention trials had reduced tsetse densities by over 90% from >3 flies/trap/day to <1fly/trap/day on Big Chamaunga and Manga islands of Lake Victoria in western Kenya. In this study, we assessed the recovery in densities of Glossina fuscipes fuscipes on the two islands and evaluated the effects vector control might have on the population structure. A before and after intervention study was undertaken on four islands of Lake Victoria in western Kenya; Small and Big Chamaunga, Manga and Rusinga Islands, two of which tsetse control intervention had previously been undertaken. Three years after intervention average G. f. fuscipes catches in biconical traps were estimated on each island. Wing centroid size (CS) (a measurement of fly size) and shape, indicators of the population structure of flies from the four islands were compared using geometric morphometric analyses. CS and shape of available female but not male tsetse wings obtained before the intervention trial on Big and Small Chamaunga islands were compared with those from the same islands after the intervention trial. G. f. fuscipes apparent density on the previous intervention islands were>9 flies/trap/day. Irrespective of sex, wing shape did not isolate tsetse based on their islands of origin. The fly size from Big and Small Chamaunga did not differ significantly before intervention trials (P = 0.728). However, three years after the intervention flies from Big Chamaunga were significantly smaller than those from Small Chamaunga (P < 0.003). Further, there was an increase in the divergence of wing morphology between flies collected from Big Chamaunga and those from Small Chamaunga after tsetse control. In conclusion, even though populations are not isolated, vector control could influence the population structure of tsetse by exerting size and wing morphology differential selection pressures. Therefore, we recommend further studies to understand the mechanism behind this as it may guide future vector control strategies.
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Kimaro EG, Toribio JALML, Gwakisa P, Mor SM. Occurrence of trypanosome infections in cattle in relation to season, livestock movement and management practices of Maasai pastoralists in Northern Tanzania. VETERINARY PARASITOLOGY- REGIONAL STUDIES AND REPORTS 2018; 12:91-98. [PMID: 31014817 DOI: 10.1016/j.vprsr.2018.02.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Revised: 02/01/2018] [Accepted: 02/21/2018] [Indexed: 11/27/2022]
Abstract
African animal trypanosomosis (AAT) is a parasitic disease considered to be one of the greatest constraints to cattle production in Tanzania. There is insufficient information on seasonal occurrence of AAT and management practices in Monduli District of the Maasai Steppe ecosystem to guide and prioritize AAT control programs. A cross-sectional survey was undertaken in 10 randomly selected villages of Monduli District. Information on seasonal animal movements, including wildlife interaction, and AAT management practices was gathered using a standardized questionnaire with 130 pastoralists. Blood samples were collected from a total of 960 cattle, in wet and dry seasons. An entomological survey was also undertaken in the dry season. Polymerase chain reaction targeting the internal transcribed spacer 1 (ITS1) was used for parasite identification in cattle blood and in tsetse flies. The overall apparent prevalence of AAT in cattle was 5.8% (95% CI of 4.1-8.3) and 4.2% (95% CI of 2.7-6.3) during wet and dry reasons, respectively. Trypanosoma vivax was the most common species identified in cattle. All tsetse flies (n = 426) collected were trapped in Esilalei village which is in close proximity to Lake Manyara National Park. Tsetse fly infection status was determined to be 7.0%; (CI 95% of 4.9-9.8%) with nearly 50% of infections due to T. congolense. All 130 cattle owners reported that they could easily recognize AAT and the majority (75%) identified the most prominent clinical signs. Nearly all owners (98.5%) identified that tsetse flies were responsible for AAT transmission. All cattle owners (100%) reported the use of trypanocides for AAT treatment, while 2.3% reported to also use herbal medicine. The trypanocides, Novidium® and Berenil®, were the most frequently reported commercial drugs and were used by 42% of cattle owners. Vector control by hand spraying was reported by the majority (90.8%) of cattle owners, while dipping and deployment of insecticide-impregnated targets were reported by few cattle owners (16.2% and 5.4%, respectively). The majority of cattle owners (83.1%) reported to move cattle away from home villages during the dry season with many migrating to areas in close proximity to wildlife parks. This study confirms the presence of circulating pathogenic trypanosomes in tsetse flies which continue to pose a threat to Maasai cattle. The seasonal movement of cattle during the dry season was associated with more clinical cases of cattle trypanosomosis. This study demonstrates the need to strengthen surveillance and control strategies for AAT.
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Affiliation(s)
- Esther G Kimaro
- School of Veterinary Science, Faculty of Science, The University of Sydney, Australia; Tropical Pesticides Research Institute, Livestock and Human Diseases Vector Control Division, P.O. Box 3420, Arusha, Tanzania
| | - Jenny-Ann L M L Toribio
- School of Veterinary Science, Faculty of Science, The University of Sydney, Australia; Marie Bashir Institute for Infectious Diseases and Biosecurity, The University of Sydney, Australia
| | - Paul Gwakisa
- Department of Microbiology, Parasitology and Biotechnology, College of Veterinary Medicine and Biomedical Sciences, Sokoine University of Agriculture, Morogoro, Tanzania
| | - Siobhan M Mor
- School of Veterinary Science, Faculty of Science, The University of Sydney, Australia; Marie Bashir Institute for Infectious Diseases and Biosecurity, The University of Sydney, Australia.
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Tekle T, Terefe G, Cherenet T, Ashenafi H, Akoda KG, Teko-Agbo A, Van Den Abbeele J, Gari G, Clausen PH, Hoppenheit A, Mattioli RC, Peter R, Marcotty T, Cecchi G, Delespaux V. Aberrant use and poor quality of trypanocides: a risk for drug resistance in south western Ethiopia. BMC Vet Res 2018; 14:4. [PMID: 29304792 PMCID: PMC5755418 DOI: 10.1186/s12917-017-1327-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Accepted: 12/22/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Trypanocidal drugs have been used to control African animal trypanosomosis for several decades. In Ethiopia, these drugs are available from both authorized (legal) and unauthorized (illegal) sources but documentation on utilization practices and quality of circulating products is scanty. This study looked at the practices of trypanocidal drug utilization by farmers and the integrity of active ingredient in trypanocides sold in Gurage zone, south western Ethiopia. The surveys were based on a structured questionnaire and drug quality determination of commonly used brands originating from European and Asian companies and sold at both authorized and unauthorized markets. One hundred farmers were interviewed and 50 drug samples were collected in 2013 (Diminazene aceturate = 33 and Isometamidium chloride = 17; 25 from authorized and 25 from unauthorized sources). Samples were tested at the OIE-certified Veterinary Drug Control Laboratory (LACOMEV) in Dakar, Senegal, by using galenic standards and high performance liquid chromatography. RESULTS Trypanosomosis was found to be a major threat according to all interviewed livestock keepers in the study area. Diminazene aceturate and isometamidium chloride were preferred by 79% and 21% of the respondents respectively, and 85% of them indicated that an animal receives more than six treatments per year. About 60% of these treatments were reported to be administered by untrained farmers. Trypanocidal drug sources included both unauthorized outlets (56%) and authorized government and private sources (44%). A wide availability and usage of substandard quality drugs was revealed. Twenty eight percent of trypanocidal drugs tested failed to comply with quality requirements. There was no significant difference in the frequency of non-compliance between diminazene-based and isometamidium chloride products (P = 0.87) irrespective of the marketing channel (official and unofficial). However, higher rates of non-compliant trypanocides were detected for drugs originating from Asia than from Europe (P = 0.029). CONCLUSION The findings revealed the presence of risk factors for the development of drug resistance, i.e. wide distribution of poor quality drugs as well as substandard administration practices. Therefore, it is strongly recommended to enforce regulatory measures for quality control of veterinary drugs, to expand and strengthen veterinary services and to undertake trypanocidal drug efficacy studies of wider coverage.
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Affiliation(s)
- T Tekle
- National Animal Health Diagnostic and Investigation Center-Protozoology unit, P.O. Box 8615, Addis Ababa, Ethiopia
| | - G Terefe
- Department of Pathology & Parasitology, Addis Ababa University College of Veterinary Medicine and Agriculture, P.O.Box 34, Bishoftu, Ethiopia.
| | - T Cherenet
- Minstry of Livestock and Fisheries, Addis Ababa, Ethiopia
| | - H Ashenafi
- Department of Pathology & Parasitology, Addis Ababa University College of Veterinary Medicine and Agriculture, P.O.Box 34, Bishoftu, Ethiopia
| | - K G Akoda
- Ecole Inter- Etats des Sciences et Médecine vétérinaires de Dakar, P.O.Box 5077, Dakar, Fann, Senegal
| | - A Teko-Agbo
- Ecole Inter- Etats des Sciences et Médecine vétérinaires de Dakar, P.O.Box 5077, Dakar, Fann, Senegal
| | - J Van Den Abbeele
- Department of Biomedical Sciences Veterinary Protozoology, Institute of Tropical Medicine, Unit 155 Nationalestraat, B-2000, Antwerp, Belgium
| | - G Gari
- National Animal Health Diagnostic and Investigation Center-Protozoology unit, P.O. Box 8615, Addis Ababa, Ethiopia
| | - P-H Clausen
- Institute for Parasitology and Tropical Veterinary Medicine, Freie Universitaet Berlin, Robert-von-Ostertag Str. 7-13, 14163, Berlin, Germany
| | - A Hoppenheit
- Institute for Parasitology and Tropical Veterinary Medicine, Freie Universitaet Berlin, Robert-von-Ostertag Str. 7-13, 14163, Berlin, Germany
| | - R C Mattioli
- Food and Agriculture Organization of the United Nations, Viale delle Terme di Caracalla, 00153, Rome, Italy
| | - R Peter
- Global Alliance for Livestock Veterinary Medicines (GALVmed), Doherty Building, Pentlands Park, Bush Loan, Edinburgh, EH26 0PZ, UK
| | - T Marcotty
- Veterinary Epidemiology and Risk Analysis - Research and Development (VERDI-R&D), Rue du Gravier 7, 4141, Sprimont, Belgium
| | - G Cecchi
- Food and Agriculture Organization of the United Nations, Sub-Regional Office for Eastern Africa, Addis Ababa, Ethiopia
| | - V Delespaux
- Faculty of Sciences and Bio-engineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050, Brussels, Belgium
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Muhanguzi D, Mugenyi A, Bigirwa G, Kamusiime M, Kitibwa A, Akurut GG, Ochwo S, Amanyire W, Okech SG, Hattendorf J, Tweyongyere R. African animal trypanosomiasis as a constraint to livestock health and production in Karamoja region: a detailed qualitative and quantitative assessment. BMC Vet Res 2017; 13:355. [PMID: 29178951 PMCID: PMC5702144 DOI: 10.1186/s12917-017-1285-z] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 11/17/2017] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND Nagana (African Animal Trypanosomiasis-AAT) and tick-borne diseases (TBDs) constrain livestock production in most parts of sub-Saharan Africa. To this realisation, Uganda government set up an African trypanosomiasis (AT) control unit, which among other activities generates national tsetse control priority maps using apparent tsetse density data. Such maps underestimate mechanically transmitted AAT and thus ought to be refined using actual AT prevalence data. We therefore set out to generate up-to-date cattle and donkey trypanosomiasis prevalence data as well as find out the constraints to livestock production in Karamoja region in a bid to re-define AT control priority in this region. RESULTS Livestock keepers and animal health workers indicated that TBDs and AAT were the most important livestock diseases in Karamoja region. The prevalence of Trypanosoma spp. in cattle and donkeys was 16.3% (95% CI: 12.4-21.1%) and 32.4% (95% CI; 20.2-47.6%) respectively. Trypanosoma vivax (12.1%) and Trypanosoma congolense savannah (29.6%) were the most prevalent Trypanosoma spp. in cattle and donkeys respectively. Majority of the cattle (85.7%) and more than half of the donkey (57.1%) herds were positive for Trypanosoma spp. CONCLUSIONS African animal trypanosomiasis and TBDs are the most important constraints to livestock production in Karamoja region. In order to improve livestock production and hence Karamajong livelihoods, government of Uganda and her development partners will need to invest in livestock health programs particularly targeting tsetse and TBD control.
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Affiliation(s)
- Dennis Muhanguzi
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, P.O. Box 7062, Kampala, Uganda
| | - Albert Mugenyi
- Coordinating Office for Control of Trypanosomiasis in Uganda, Ministry of Agriculture, Animal Industry and Fisheries, Plot 78, Buganda Road, P. O. Box: 16345 Wandegeya, Kampala, Uganda
| | - Godfrey Bigirwa
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, P.O. Box 7062, Kampala, Uganda
| | | | - Ann Kitibwa
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, P.O. Box 7062, Kampala, Uganda
| | - Grace Gloria Akurut
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, P.O. Box 7062, Kampala, Uganda
| | - Sylvester Ochwo
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, P.O. Box 7062, Kampala, Uganda
| | - Wilson Amanyire
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, P.O. Box 7062, Kampala, Uganda
| | - Samuel George Okech
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, P.O. Box 7062, Kampala, Uganda
| | - Jan Hattendorf
- Swiss Tropical Institute, Socinstrasse 57, -4002 Basel, CH Switzerland
- University of Basel, Petersplatz 1, 4003 Basel, Switzerland
| | - Robert Tweyongyere
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, P.O. Box 7062, Kampala, Uganda
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