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Morenikeji OB, Metelski JL, Grytsay A, Soulas J, Akinyemi MO, Thomas BN. Molecular genotyping reveals mixed bovine and human trypanosomiasis in cattle from West Africa. Vet World 2023; 16:149-153. [PMID: 36855345 PMCID: PMC9967721 DOI: 10.14202/vetworld.2023.149-153] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 11/30/2022] [Indexed: 01/25/2023] Open
Abstract
Background and Aim Animal trypanosomiasis is a major contributor to agricultural and economic losses, especially in sub-Saharan Africa. We have shown that some animal species expressed genes that are significant players in immune response to bovine trypanosomosis, impeding signs and symptoms of the disease. We hypothesize that such animals are contributors to disease transmission dynamics and severe outcomes. Therefore, this study aims to ascertain trypanosome species diversity in cattle and their potential role as reservoirs for the transmission of human disease. Materials and Methods We performed a molecular genotyping of trypanosome internal transcribed spacer 1 (ITS-1) and 18S ribosomal RNA genes on genomic DNA extracts from randomly sampled N'Dama cattle from slaughterhouses in Nigeria. We identified trypanosome species circulating among the animals through polymerase chain reaction and genomic sequencing. We performed multiple sequence alignments as well as conducted a phylogenetic relationship between identified species. Results In all, 9 of 127 (7.1%) samples were positively amplified (band sizes ranging from 250 bp to 710 bp), including an isolate with two distinct bands (700 and 710 bp), indicating two trypanosome types. Sequence similarity and homology analysis identified four species, namely: Trypanosoma vivax, Trypanosoma congolense forest type, T. congolense savannah type, and Trypanosoma brucei. Interestingly, one of the bands, additionally verified by nucleotide sequencing, was identified as a human trypanosome (Trypanosoma brucei gambiense), confirming our hypothesis that cattle are potential reservoir hosts for human trypanosomes. Conclusion Overall, we observed different trypanosome species in our study area, with animals on the same farm infected with multiple species, which could complicate treatment and disease control strategies. Finding human trypanosome species strengthens the argument that disease transmission dynamics are modulated by other vertebrates, further complicating control programs.
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Affiliation(s)
- Olanrewaju B. Morenikeji
- Division of Biological Health Sciences, University of Pittsburgh, Bradford, PA, 16701, United States,Corresponding authors: Olanrewaju B. Morenikeji, e-mail: ; Bolaji N. Thomas, e-mail: Co-authors: JLM: , AG: , JS: , MOA:
| | - Jessica L. Metelski
- Department of Biomedical Sciences, Rochester Institute of Technology, Rochester, NY 14623, United States
| | - Anastasia Grytsay
- Division of Biological Health Sciences, University of Pittsburgh, Bradford, PA, 16701, United States
| | - Jacob Soulas
- Division of Biological Health Sciences, University of Pittsburgh, Bradford, PA, 16701, United States
| | - Mabel O. Akinyemi
- Department of Biological Sciences, Fairleigh Dickinson University, Madison, NJ 07940, United States
| | - Bolaji N. Thomas
- Department of Biomedical Sciences, Rochester Institute of Technology, Rochester, NY 14623, United States
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2
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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: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [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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3
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Zhang Y, Ceylan Koydemir H, Shimogawa MM, Yalcin S, Guziak A, Liu T, Oguz I, Huang Y, Bai B, Luo Y, Luo Y, Wei Z, Wang H, Bianco V, Zhang B, Nadkarni R, Hill K, Ozcan A. Motility-based label-free detection of parasites in bodily fluids using holographic speckle analysis and deep learning. LIGHT, SCIENCE & APPLICATIONS 2018; 7:108. [PMID: 30564314 PMCID: PMC6290798 DOI: 10.1038/s41377-018-0110-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2018] [Revised: 11/25/2018] [Accepted: 11/25/2018] [Indexed: 05/08/2023]
Abstract
Parasitic infections constitute a major global public health issue. Existing screening methods that are based on manual microscopic examination often struggle to provide sufficient volumetric throughput and sensitivity to facilitate early diagnosis. Here, we demonstrate a motility-based label-free computational imaging platform to rapidly detect motile parasites in optically dense bodily fluids by utilizing the locomotion of the parasites as a specific biomarker and endogenous contrast mechanism. Based on this principle, a cost-effective and mobile instrument, which rapidly screens ~3.2 mL of fluid sample in three dimensions, was built to automatically detect and count motile microorganisms using their holographic time-lapse speckle patterns. We demonstrate the capabilities of our platform by detecting trypanosomes, which are motile protozoan parasites, with various species that cause deadly diseases affecting millions of people worldwide. Using a holographic speckle analysis algorithm combined with deep learning-based classification, we demonstrate sensitive and label-free detection of trypanosomes within spiked whole blood and artificial cerebrospinal fluid (CSF) samples, achieving a limit of detection of ten trypanosomes per mL of whole blood (~five-fold better than the current state-of-the-art parasitological method) and three trypanosomes per mL of CSF. We further demonstrate that this platform can be applied to detect other motile parasites by imaging Trichomonas vaginalis, the causative agent of trichomoniasis, which affects 275 million people worldwide. With its cost-effective, portable design and rapid screening time, this unique platform has the potential to be applied for sensitive and timely diagnosis of neglected tropical diseases caused by motile parasites and other parasitic infections in resource-limited regions.
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Affiliation(s)
- Yibo Zhang
- Electrical and Computer Engineering Department, University of California, Los Angeles, CA 90095 USA
- Bioengineering Department, University of California, Los Angeles, CA 90095 USA
- California NanoSystems Institute, University of California, Los Angeles, CA 90095 USA
| | - Hatice Ceylan Koydemir
- Electrical and Computer Engineering Department, University of California, Los Angeles, CA 90095 USA
- Bioengineering Department, University of California, Los Angeles, CA 90095 USA
- California NanoSystems Institute, University of California, Los Angeles, CA 90095 USA
| | - Michelle M. Shimogawa
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, CA 90095 USA
| | - Sener Yalcin
- Electrical and Computer Engineering Department, University of California, Los Angeles, CA 90095 USA
| | - Alexander Guziak
- Department of Physics and Astronomy, University of California, Los Angeles, CA 90095 USA
| | - Tairan Liu
- Electrical and Computer Engineering Department, University of California, Los Angeles, CA 90095 USA
- Bioengineering Department, University of California, Los Angeles, CA 90095 USA
- California NanoSystems Institute, University of California, Los Angeles, CA 90095 USA
| | - Ilker Oguz
- Electrical and Computer Engineering Department, University of California, Los Angeles, CA 90095 USA
| | - Yujia Huang
- Electrical and Computer Engineering Department, University of California, Los Angeles, CA 90095 USA
| | - Bijie Bai
- Electrical and Computer Engineering Department, University of California, Los Angeles, CA 90095 USA
| | - Yilin Luo
- Electrical and Computer Engineering Department, University of California, Los Angeles, CA 90095 USA
| | - Yi Luo
- Electrical and Computer Engineering Department, University of California, Los Angeles, CA 90095 USA
- Bioengineering Department, University of California, Los Angeles, CA 90095 USA
- California NanoSystems Institute, University of California, Los Angeles, CA 90095 USA
| | - Zhensong Wei
- Electrical and Computer Engineering Department, University of California, Los Angeles, CA 90095 USA
| | - Hongda Wang
- Electrical and Computer Engineering Department, University of California, Los Angeles, CA 90095 USA
- Bioengineering Department, University of California, Los Angeles, CA 90095 USA
- California NanoSystems Institute, University of California, Los Angeles, CA 90095 USA
| | - Vittorio Bianco
- Electrical and Computer Engineering Department, University of California, Los Angeles, CA 90095 USA
| | - Bohan Zhang
- Electrical and Computer Engineering Department, University of California, Los Angeles, CA 90095 USA
| | - Rohan Nadkarni
- Bioengineering Department, University of California, Los Angeles, CA 90095 USA
| | - Kent Hill
- California NanoSystems Institute, University of California, Los Angeles, CA 90095 USA
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, CA 90095 USA
- Molecular Biology Institute, University of California, Los Angeles, CA 90095 USA
| | - Aydogan Ozcan
- Electrical and Computer Engineering Department, University of California, Los Angeles, CA 90095 USA
- Bioengineering Department, University of California, Los Angeles, CA 90095 USA
- California NanoSystems Institute, University of California, Los Angeles, CA 90095 USA
- Department of Surgery, David Geffen School of Medicine, University of California, Los Angeles, CA 90095 USA
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4
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Radwanska M, Vereecke N, Deleeuw V, Pinto J, Magez S. Salivarian Trypanosomosis: A Review of Parasites Involved, Their Global Distribution and Their Interaction With the Innate and Adaptive Mammalian Host Immune System. Front Immunol 2018; 9:2253. [PMID: 30333827 PMCID: PMC6175991 DOI: 10.3389/fimmu.2018.02253] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 09/11/2018] [Indexed: 01/27/2023] Open
Abstract
Salivarian trypanosomes are single cell extracellular parasites that cause infections in a wide range of hosts. Most pathogenic infections worldwide are caused by one of four major species of trypanosomes including (i) Trypanosoma brucei and the human infective subspecies T. b. gambiense and T. b. rhodesiense, (ii) Trypanosoma evansi and T. equiperdum, (iii) Trypanosoma congolense and (iv) Trypanosoma vivax. Infections with these parasites are marked by excessive immune dysfunction and immunopathology, both related to prolonged inflammatory host immune responses. Here we review the classification and global distribution of these parasites, highlight the adaptation of human infective trypanosomes that allow them to survive innate defense molecules unique to man, gorilla, and baboon serum and refer to the discovery of sexual reproduction of trypanosomes in the tsetse vector. With respect to the immunology of mammalian host-parasite interactions, the review highlights recent findings with respect to the B cell destruction capacity of trypanosomes and the role of T cells in the governance of infection control. Understanding infection-associated dysfunction and regulation of both these immune compartments is crucial to explain the continued failures of anti-trypanosome vaccine developments as well as the lack of any field-applicable vaccine based anti-trypanosomosis intervention strategy. Finally, the link between infection-associated inflammation and trypanosomosis induced anemia is covered in the context of both livestock and human infections.
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Affiliation(s)
- Magdalena Radwanska
- Laboratory for Biomedical Research, Ghent University Global Campus, Incheon, South Korea
| | - Nick Vereecke
- Laboratory for Biomedical Research, Ghent University Global Campus, Incheon, South Korea.,Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Violette Deleeuw
- Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Joar Pinto
- Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Stefan Magez
- Laboratory for Biomedical Research, Ghent University Global Campus, Incheon, South Korea.,Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel, Brussels, Belgium
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5
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Luryama Moi K, Obol JH, Anywar Arony D. Identification of human African Trypanosomiasis foci using school-going children in post-conflict era in Nwoya District, Northern Uganda: A cross-sectional study. AAS Open Res 2018; 1:8. [PMID: 32382695 PMCID: PMC7194148 DOI: 10.12688/aasopenres.12851.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/10/2018] [Indexed: 11/20/2022] Open
Abstract
Background: Human African Trypanosomiasis (HAT) is fatal if untreated; the drugs to treat it are toxic making its management difficult and diagnosis complex. Nwoya district has a long history of sleeping-sickness dating back to pre-colonial times. The civil war of 1986-2008 displaced many who upon return complained of cattle and dogs dying of unknown causes alongside increased tsetse flies infestation hence, the needs for the study. Methods: We enrolled local 3,040 pupils and recorded their social-demographic characteristics and access to different domesticated animals/fowls in their homes. Screening for HAT using the card agglutination test for trypanosomiasis (CATT) was performed; positive individuals had their titres determined, followed by microscopy and loop mediated isothermal amplification analysis (LAMP). R was used for analysis where associations were sought between dependent and independent variables. Any factor with P-value <0.05 was taken as statistically significant. Results: HAT serological prevalence of 1.2% (95% CI 0.8-1.6) was obtained, 58.3% being boys while 41.7% were girls with titres ranging from 1:2 - 1:16. Two schools alone, constituted 47% of the CATT positive cases. Pupils who came from homes with dogs were more likely to be CATT/ Trypanosoma brucei gambiense positive; (adjusted odds ratio = 3.12, 95% CI 1.41-6.99 & p=0.005). Conclusions: Though no parasites were detected, with prevalence of CATT positive at 1.2%, active surveillance in the district is still recommended. CATT positive cases needs follow-ups were immune trypanolysis test done to ascertain their exposure.
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Affiliation(s)
- Kenneth Luryama Moi
- Department of Medical Microbiology & Immunology, Faculty of Medicine, Gulu University, Gulu, Uganda
| | - James Henry Obol
- Department of Public Health, Faculty of Medicine, Gulu University, Gulu, Uganda
| | - Denis Anywar Arony
- Department of Medical Biochemistry, Faculty of Medicine, Gulu University, Gulu, Uganda
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6
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A co-evolutionary arms race: trypanosomes shaping the human genome, humans shaping the trypanosome genome. Parasitology 2017; 142 Suppl 1:S108-19. [PMID: 25656360 PMCID: PMC4413828 DOI: 10.1017/s0031182014000602] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Trypanosoma brucei is the causative agent of African sleeping sickness in humans and one of several pathogens that cause the related veterinary disease Nagana. A complex co-evolution has occurred between these parasites and primates that led to the emergence of trypanosome-specific defences and counter-measures. The first line of defence in humans and several other catarrhine primates is the trypanolytic protein apolipoprotein-L1 (APOL1) found within two serum protein complexes, trypanosome lytic factor 1 and 2 (TLF-1 and TLF-2). Two sub-species of T. brucei have evolved specific mechanisms to overcome this innate resistance, Trypanosoma brucei gambiense and Trypanosoma brucei rhodesiense. In T. b. rhodesiense, the presence of the serum resistance associated (SRA) gene, a truncated variable surface glycoprotein (VSG), is sufficient to confer resistance to lysis. The resistance mechanism of T. b. gambiense is more complex, involving multiple components: reduction in binding affinity of a receptor for TLF, increased cysteine protease activity and the presence of the truncated VSG, T. b. gambiense-specific glycoprotein (TgsGP). In a striking example of co-evolution, evidence is emerging that primates are responding to challenge by T. b. gambiense and T. b. rhodesiense, with several populations of humans and primates displaying resistance to infection by these two sub-species.
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7
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Alhaji NB, Kabir J. Influence of Pastoralists' Sociocultural Activities on Tsetse-Trypanosome-Cattle Reservoir Interface: The Risk of Human African Trypanosomiasis in North-Central Nigeria. Zoonoses Public Health 2015; 63:271-80. [PMID: 26355707 DOI: 10.1111/zph.12226] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Indexed: 11/29/2022]
Abstract
The study investigated socio-cultural characteristics of pastoralists that influenced on the tsetse-trypanosome-cattle reservoir interface thereby predisposing them to HAT in Niger State, North-central Nigeria. It was a cross-sectional survey of adult pastoral herders, aged 30 years and above, and conducted between October 2012 and February 2013. A face-to-face structured questionnaire was administered on the pastoralists nested in 96 cattle herds with questions focused on pastoralists' socio-cultural activities and behavioral practices related to HAT risk. Descriptive and analytic statistics were used to describe the obtained data. A total of 384 pastoralists participated, with mean age of 49.6 Â ± 10.76 SD years. Male respondents constituted 86.7% of gender, while pastoralists of age group 40-49 years constituted 35.4% of respondents. About 59.4% of the pastoralists had knowledge about HAT and its symptoms and only 33.9% of them believed that cattle served as reservoir of HAT trypanosome. Knowledge/belief levels of the pastoralists about African trypanosomiasis occurrence in humans and animals were statistically significant. Males were four times more likely to be exposed to HAT (OR = 3.67; 95% CI: 1.42, 9.52); age group 60-69 was also four times more likely to be exposed (OR = 3.59; 95% CI: 1.56, 8.28); and nomadic pastoralists were two times more likely to be exposed to HAT (OR = 2.07; 95% CI: 1.37, 3.14). All cultural practices significantly influenced exposure to HAT with extensive husbandry system three times more likely to predisposed pastoralists to HAT (OR = 3.21; 95% CI: 1.65, 6.24). Socio-cultural characteristics of pastoralists influenced exposure to HAT risk and, therefore, there is a need to sensitize them to bring changes to their socio-cultural practices and perceptions to achieve effective and long term sustainable HAT control. Elimination strategies of parasites in animals and vectors should be considered to avoid reintroduction from animal reservoirs.
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Affiliation(s)
- N B Alhaji
- Nigerian Field Epidemiology and Laboratory Training Program (NFELTP), Asokoro-Abuja, Nigeria.,Zoonoses and Epidemiology Unit, Niger State Ministry of Livestock and Fisheries Development, Minna, Nigeria
| | - J Kabir
- Department of Veterinary Public Health and Preventive Medicine, Ahmadu Bello University, Zaria, Nigeria
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8
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Genetic diversity and population structure of Trypanosoma brucei in Uganda: implications for the epidemiology of sleeping sickness and Nagana. PLoS Negl Trop Dis 2015; 9:e0003353. [PMID: 25695634 PMCID: PMC4335064 DOI: 10.1371/journal.pntd.0003353] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2014] [Accepted: 10/15/2014] [Indexed: 11/19/2022] Open
Abstract
Background While Human African Trypanosomiasis (HAT) is in decline on the continent of Africa, the disease still remains a major health problem in Uganda. There are recurrent sporadic outbreaks in the traditionally endemic areas in south-east Uganda, and continued spread to new unaffected areas in central Uganda. We evaluated the evolutionary dynamics underpinning the origin of new foci and the impact of host species on parasite genetic diversity in Uganda. We genotyped 269 Trypanosoma brucei isolates collected from different regions in Uganda and southwestern Kenya at 17 microsatellite loci, and checked for the presence of the SRA gene that confers human infectivity to T. b. rhodesiense. Results Both Bayesian clustering methods and Discriminant Analysis of Principal Components partition Trypanosoma brucei isolates obtained from Uganda and southwestern Kenya into three distinct genetic clusters. Clusters 1 and 3 include isolates from central and southern Uganda, while cluster 2 contains mostly isolates from southwestern Kenya. These three clusters are not sorted by subspecies designation (T. b. brucei vs T. b. rhodesiense), host or date of collection. The analyses also show evidence of genetic admixture among the three genetic clusters and long-range dispersal, suggesting recent and possibly on-going gene flow between them. Conclusions Our results show that the expansion of the disease to the new foci in central Uganda occurred from the northward spread of T. b. rhodesiense (Tbr). They also confirm the emergence of the human infective strains (Tbr) from non-infective T. b. brucei (Tbb) strains of different genetic backgrounds, and the importance of cattle as Tbr reservoir, as confounders that shape the epidemiology of sleeping sickness in the region. Human African Trypanosomiasis (HAT) is a major health problem in Uganda, as there are recurrent sporadic outbreaks of the disease in traditionally endemic areas in south-east Uganda, and continued spread to new unaffected areas in central Uganda. In this study, we evaluate the evolutionary dynamics underpinning the origin of new disease foci and the impact of host species on parasite genetic diversity in Uganda. We found three distinct genetic clusters of T. brucei in Uganda and southwestern Kenya. Clusters 1 and 3 include isolates from central and southern Uganda, while cluster 2 contains mostly isolates from southwestern Kenya. These three clusters are not sorted by subspecies designation (T. b. brucei vs T. b. rhodesiense), host or date of collection. Our results show expansion of the disease to new foci in central Uganda occurred from the northward spread of T. b. rhodesiense. They also confirm the emergence of the human infective strains from non-infective T. b. brucei strains of different genetic backgrounds, and the importance of cattle as Tbr reservoir, as confounders that shape the epidemiology of sleeping sickness in the region.
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9
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Abstract
African trypanosomes have been around for more than 100 million years, and have adapted to survival in a very wide host range. While various indigenous African mammalian host species display a tolerant phenotype towards this parasitic infection, and hence serve as perpetual reservoirs, many commercially important livestock species are highly disease susceptible. When considering humans, they too display a highly sensitive disease progression phenotype for infections with Trypanosoma brucei rhodesiense or Trypanosoma brucei gambiense, while being intrinsically resistant to infections with other trypanosome species. As extracellular trypanosomes proliferate and live freely in the bloodstream and lymphatics, they are constantly exposed to the immune system. Due to co-evolution, this environment however no longer poses a hostile threat, but has become the niche environment where trypanosomes thrive and obligatory await transmission through the bites of tsetse flies or other haematophagic vectors, ideally without causing severe side infection-associated pathology to their host. Hence, African trypanosomes have acquired various mechanisms to manipulate and control the host immune response, evading effective elimination. Despite the extensive research into trypanosomosis over the past 40 years, many aspects of the anti-parasite immune response remain to be solved and no vaccine is currently available. Here we review the recent work on the different escape mechanisms employed by African Trypanosomes to ensure infection chronicity and transmission potential.
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10
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Capewell P, Cooper A, Duffy CW, Tait A, Turner CMR, Gibson W, Mehlitz D, MacLeod A. Human and animal Trypanosomes in Côte d'Ivoire form a single breeding population. PLoS One 2013; 8:e67852. [PMID: 23844111 PMCID: PMC3699513 DOI: 10.1371/journal.pone.0067852] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Accepted: 05/22/2013] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND Trypanosoma brucei is the causative agent of African Sleeping Sickness in humans and contributes to the related veterinary disease, Nagana. T. brucei is segregated into three subspecies based on host specificity, geography and pathology. T. b. brucei is limited to animals (excluding some primates) throughout sub-Saharan Africa and is non-infective to humans due to trypanolytic factors found in human serum. T. b. gambiense and T. b. rhodesiense are human infective sub-species. T. b. gambiense is the more prevalent human, causing over 97% of human cases. Study of T. b. gambiense is complicated in that there are two distinct groups delineated by genetics and phenotype. The relationships between the two groups and local T. b. brucei are unclear and may have a bearing on the evolution of the human infectivity traits. METHODOLOGY/PRINCIPAL FINDINGS A collection of sympatric T. brucei isolates from Côte d'Ivoire, consisting of T. b. brucei and both groups of T. b. gambiense have previously been categorized by isoenzymes, RFLPs and Blood Incubation Infectivity Tests. These samples were further characterized using the group 1 specific marker, TgSGP, and seven microsatellites. The relationships between the T. b. brucei and T. b. gambiense isolates were determined using principal components analysis, neighbor-joining phylogenetics, STRUCTURE, FST, Hardy-Weinberg equilibrium and linkage disequilibrium. CONCLUSIONS/SIGNIFICANCE Group 1 T. b. gambiense form a clonal genetic group, distinct from group 2 and T. b. brucei, whereas group 2 T. b. gambiense are genetically indistinguishable from local T. b. brucei. There is strong evidence for mating within and between group 2 T. b. gambiense and T. b. brucei. We found no evidence to support the hypothesis that group 2 T. b. gambiense are hybrids of group 1 and T. b. brucei, suggesting that human infectivity has evolved independently in groups 1 and 2 T. b. gambiense.
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Affiliation(s)
- Paul Capewell
- Wellcome Trust Centre for Molecular Parasitology, College of Medical, Veterinary and Biological Sciences, Glasgow, United Kingdom
| | - Anneli Cooper
- Wellcome Trust Centre for Molecular Parasitology, College of Medical, Veterinary and Biological Sciences, Glasgow, United Kingdom
| | - Craig W. Duffy
- Wellcome Trust Centre for Molecular Parasitology, College of Medical, Veterinary and Biological Sciences, Glasgow, United Kingdom
| | - Andy Tait
- Wellcome Trust Centre for Molecular Parasitology, College of Medical, Veterinary and Biological Sciences, Glasgow, United Kingdom
| | | | - Wendy Gibson
- School of Biological Sciences, University of Bristol, Bristol, United Kingdom
| | - Dieter Mehlitz
- Institute for Parasitology and Tropical Veterinary Medicine, Freie Universität Berlin, Berlin, Germany
| | - Annette MacLeod
- Wellcome Trust Centre for Molecular Parasitology, College of Medical, Veterinary and Biological Sciences, Glasgow, United Kingdom
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11
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Rutto JJ, Osano O, Thuranira EG, Kurgat RK, Odenyo VAO. Socio-economic and cultural determinants of human african trypanosomiasis at the Kenya - Uganda transboundary. PLoS Negl Trop Dis 2013; 7:e2186. [PMID: 23638206 PMCID: PMC3636132 DOI: 10.1371/journal.pntd.0002186] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2012] [Accepted: 03/20/2013] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Kenya and Uganda have reported different Human African Trypanosomiasis incidences in the past more than three decades, with the latter recording more cases. This cross-sectional study assessed the demographic characteristics, tsetse and trypanosomiasis control practices, socio-economic and cultural risk factors influencing Trypanosoma brucei rhodesiense (T.b.r.) infection in Teso and Busia Districts, Western Kenya and Tororo and Busia Districts, Southeast Uganda. A conceptual framework was postulated to explain interactions of various socio-economic, cultural and tsetse control factors that predispose individuals and populations to HAT. METHODS A cross-sectional household survey was conducted between April and October 2008. Four administrative districts reporting T.b.r and lying adjacent to each other at the international boundary of Kenya and Uganda were purposely selected. Household data collection was carried out in two villages that had experienced HAT and one other village that had no reported HAT case from 1977 to 2008 in each district. A structured questionnaire was administered to 384 randomly selected household heads or their representatives in each country. The percent of respondents giving a specific answer was reported. Secondary data was also obtained on socio-economic and political issues in both countries. RESULTS Inadequate knowledge on the disease cycle and intervention measures contributed considerable barriers to HAT, and more so in Uganda than in Kenya. Gender-associated socio-cultural practices greatly predisposed individuals to HAT. Pesticides-based crop husbandry in the 1970's reportedly reduced vector population while vegetation of coffee and banana's and livestock husbandry directly increased occurrence of HAT. Livestock husbandry practices in the villages were strong predictors of HAT incidence. The residents in Kenya (6.7%) applied chemoprophylaxis and chemotherapeutic controls against trypanosomiasis to a larger extent than Uganda (2.1%). CONCLUSION Knowledge on tsetse and its control methods, culture, farming practice, demographic and socio-economic variables explained occurrence of HAT better than landscape features.
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Affiliation(s)
- Jane Jemeli Rutto
- Kenya Agricultural Research Institute, Trypanosomiasis Research Centre, Kikuyu, Kenya.
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Balyeidhusa ASP, Kironde FAS, Enyaru JCK. Apparent lack of a domestic animal reservoir in Gambiense sleeping sickness in northwest Uganda. Vet Parasitol 2011; 187:157-67. [PMID: 22245071 DOI: 10.1016/j.vetpar.2011.12.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2011] [Revised: 12/06/2011] [Accepted: 12/13/2011] [Indexed: 11/17/2022]
Abstract
The role played by domestic animals in the transmission of gambiense Human African Trypanosomosis remains uncertain. Northwest Uganda is endemic for Trypanosoma brucei gambiense. Of the 3267 blood samples from domestic animals in four counties examined by hematocrit centrifugation technique (HCT), 210 (6.4%) were positive for trypanosomes. The prevalence of animal trypanosomosis was estimated at 13.8% in Terego County, 4.2% in East Moyo County, 3.1% in Koboko County, and zero in West Moyo County. The trypanosome infection rates varied from 0.2% in goats, 3.5% in dogs, 5.0% in sheep, 7.5% in cattle, to 15.5% in pigs. DNA was extracted from the blood samples by Chelex method, Sigma and Qiagen DNA extraction Kits. A total of 417(12.8%) DNA samples tested positive by polymerase chain reaction (PCR) using T. brucei species specific primers (TBR) indicating that the DNA was of Trypanozoon trypanosomes while 2850 (87.2%) samples were TBR-PCR negative. The T. brucei infection rates based on TBR-PCR were highest in pigs with 21.7%, followed by cattle (14.5%), dogs (12.4%), sheep (10.8%), and lowest in goats with 3.2%, which indicated that pigs were most bitten by infected tsetse than other domestic animals. TBR-PCR detected 6.3% more infected domestic animals that had been missed, and confirmed the 6.4% cases detected by HCT in the field. Statistical analysis done using one-way ANOVA Kruskal-Wallis test (Prism version 5.0) showed no significant difference in trypanosome infections among domestic animals using both HCT and TBR-PCR techniques in the different counties (Confidence Interval of 95%, p-values >0.05). All the 417 trypanosome DNA samples were negative by PCR using two sets of primers specific for the T. b. gambiense specific glycoprotein gene and serum resistance associated gene of T. b. rhodesiense, indicating that they were probably not from the two human infective trypanosomes. Polymerase chain reaction using primers based on ribosomal internal transcribed spacer-1 region (ITS-PCR) resolved the 417 DNA of trypanosome samples into 323 (77.5%) as single trypanosome infections due to T. brucei and 39 (9.4%) mixed infections but missed detecting 55 (13.1%) samples, possibly because of the low sensitivity of ITS-PCR as compared to TBR-PCR. The 31 mixed infections were due to T. brucei (T.b) and T. vivax (T.v); while 8 mixed infections were of T. congolense (T.c) and T. brucei but no mixed trypanosome infections with T. congolense, T. brucei, and T. vivax were detected. Statistical analysis done using one way ANOVA Kruskal-Wallis test (Prism version 5.0) to compare single and mixed trypanosome infections showed no significant difference in trypanosome infections due to single (T.v, T.b, T.c) and mixed (T.v+T.b; T.v+T.c; T.b+T.c; T.v+T.b+T.c) trypanosome species among domestic animals in the different counties using ITS-PCR technique (Confidence Interval of 95%, p-values >0.05). It was concluded that domestic animals in northwest Uganda were probably not reservoirs of T. b. gambiense and there was no infection, as yet, with T. b. rhodesiense parasites.
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Goto Y, Duthie MS, Nguyen TT, Asada M, Kawazu SI, Carter D, Inoue N. Serological characterizations of tandem repeat proteins for detection of African trypanosome infection in cattle. Parasitol Int 2011; 60:538-40. [PMID: 21944942 DOI: 10.1016/j.parint.2011.09.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2011] [Revised: 07/05/2011] [Accepted: 09/07/2011] [Indexed: 12/19/2022]
Abstract
Serological diagnosis is a useful method to detect African trypanosome infection in livestock animals. Currently available serological tests utilize whole parasites or crude antigens, and recombinant antigens may improve reproducibility/standardization and reduce production costs. With a goal of identifying such recombinant proteins, we computationally identified proteins with tandem repeat (TR) domain from the parasite proteomes and evaluated their potential for serological diagnosis of African trypanosome infections in cattle. Among those tested, Tbg4 demonstrated the best performance with 92% sensitivity, followed by TbbGM6 (85%), TcoGM6 (85%), Tbg2 (65%) and Tbg5 (65%). Although further evaluations such as investigating cross-reactivity to other infections are needed, our data indicate the potential of these antigens for detection of African trypanosome infection in cattle.
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Affiliation(s)
- Yasuyuki Goto
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Japan.
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14
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Differences between Trypanosoma brucei gambiense groups 1 and 2 in their resistance to killing by trypanolytic factor 1. PLoS Negl Trop Dis 2011; 5:e1287. [PMID: 21909441 PMCID: PMC3167774 DOI: 10.1371/journal.pntd.0001287] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2011] [Accepted: 07/04/2011] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The three sub-species of Trypanosoma brucei are important pathogens of sub-Saharan Africa. T. b. brucei is unable to infect humans due to sensitivity to trypanosome lytic factors (TLF) 1 and 2 found in human serum. T. b. rhodesiense and T. b. gambiense are able to resist lysis by TLF. There are two distinct sub-groups of T. b. gambiense that differ genetically and by human serum resistance phenotypes. Group 1 T. b. gambiense have an invariant phenotype whereas group 2 show variable resistance. Previous data indicated that group 1 T. b. gambiense are resistant to TLF-1 due in-part to reduced uptake of TLF-1 mediated by reduced expression of the TLF-1 receptor (the haptoglobin-hemoglobin receptor (HpHbR)) gene. Here we investigate if this is also true in group 2 parasites. METHODOLOGY Isogenic resistant and sensitive group 2 T. b. gambiense were derived and compared to other T. brucei parasites. Both resistant and sensitive lines express the HpHbR gene at similar levels and internalized fluorescently labeled TLF-1 similar fashion to T. b. brucei. Both resistant and sensitive group 2, as well as group 1 T. b. gambiense, internalize recombinant APOL1, but only sensitive group 2 parasites are lysed. CONCLUSIONS Our data indicate that, despite group 1 T. b. gambiense avoiding TLF-1, it is resistant to the main lytic component, APOL1. Similarly group 2 T. b. gambiense is innately resistant to APOL1, which could be based on the same mechanism. However, group 2 T. b. gambiense variably displays this phenotype and expression does not appear to correlate with a change in expression site or expression of HpHbR. Thus there are differences in the mechanism of human serum resistance between T. b. gambiense groups 1 and 2.
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Prevalence of Trypanosoma sp. in cattle from Tanzania estimated by conventional PCR and loop-mediated isothermal amplification (LAMP). Parasitol Res 2011; 109:1735-9. [PMID: 21739311 DOI: 10.1007/s00436-011-2513-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2011] [Accepted: 06/22/2011] [Indexed: 10/18/2022]
Abstract
This study compared the prevalence of trypanosome infections estimated by PFR-loop-mediated isothermal amplification (LAMP) with conventional polymerase chain reaction (PCR) tests. One hundred forty eight cattle blood samples were collected from Robanda village, Mara region, Tanzania in April 2008. In conventional PCR, four sets of primers, specific for the detection of Trypanosoma sp., Trypanosoma brucei rhodesiense, Trypanosoma vivax, and Trypanozoon, as well as a modified LAMP were used. Conventional PCR detected no infection or up to 8, 1, and 3 infections with Trypanosoma congolense savannah, Trypanozoon, and T. vivax, respectively, whereas LAMP detected additional 44 Trypanozoon positive cases. Our results clearly indicate that the prevalence of Trypanozoon spp. in cattle in Robanda village estimated by PFR-LAMP (30.4%) was significantly higher than the estimates by PCR assays (0.6-2%). As such, future studies should target epidemiological surveys of Trypanozoon and T. brucei rhodesiense infections in possible reservoir animals by LAMP to further elucidate the actual prevalence of these parasites.
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Abstract
Human African trypanosomiasis (sleeping sickness) occurs in sub-Saharan Africa. It is caused by the protozoan parasite Trypanosoma brucei, transmitted by tsetse flies. Almost all cases are due to Trypanosoma brucei gambiense, which is indigenous to west and central Africa. Prevalence is strongly dependent on control measures, which are often neglected during periods of political instability, thus leading to resurgence. With fewer than 12 000 cases of this disabling and fatal disease reported per year, trypanosomiasis belongs to the most neglected tropical diseases. The clinical presentation is complex, and diagnosis and treatment difficult. The available drugs are old, complicated to administer, and can cause severe adverse reactions. New diagnostic methods and safe and effective drugs are urgently needed. Vector control, to reduce the number of flies in existing foci, needs to be organised on a pan-African basis. WHO has stated that if national control programmes, international organisations, research institutes, and philanthropic partners engage in concerted action, elimination of this disease might even be possible.
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Affiliation(s)
- Reto Brun
- Swiss Tropical Institute, Basel, Switzerland.
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Jing Z, Magona JW, Sakurai T, Thekisoe OMM, Otim CP, Sugimoto C, Inoue N. A field study to estimate the prevalence of bovine African Trypanosomosis in Butaleja District, Uganda. J Vet Med Sci 2009; 71:525-7. [PMID: 19420862 DOI: 10.1292/jvms.71.525] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Prevalence of bovine trypanosomosis was determined from a total of 203 blood samples collected from Butaleja district, eastern Uganda. All samples were examined by microhematocrit centrifuge test (MHC), PCR and ELISA. ELISA was performed in accordance with the OIE standard procedures using Trypanosoma brucei gambiense procyclic form crude antigens. PCR were utilized to identify the species and the subspecies of trypanosome. The overall prevalence of bovine African trypanosomosis was 8.9% by MHC, and 45.3% by the ELISA. Since substantial number (12 out of 18) of MHC positive samples were negative in the PCR tests, we could not conclude the most epidemic trypanosome species in the studied area. Nevertheless, the PCR results suggests that the most prevalent trypanosome was T. b. brucei (31/203), followed by T. congolense (6/203). In addition, only a few (3/203) mixed infections of T. b. brucei and T. congolense was detected by the PCR. Results obtained from this study indicates that bovine trypanosomosis is endemic in Butaleja district, Uganda.
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Affiliation(s)
- Zhang Jing
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Japan
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Cordon-Obras C, Berzosa P, Ndong-Mabale N, Bobuakasi L, Buatiche JN, Ndongo-Asumu P, Benito A, Cano J. Trypanosoma brucei gambiensein domestic livestock of Kogo and Mbini foci (Equatorial Guinea). Trop Med Int Health 2009; 14:535-41. [DOI: 10.1111/j.1365-3156.2009.02271.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Konnai S, Mekata H, Odbileg R, Simuunza M, Chembensof M, Witola WH, Tembo ME, Chitambo H, Inoue N, Onuma M, Ohashi K. Detection ofTrypanosoma bruceiin Field-Captured Tsetse Flies and Identification of Host Species Fed on by the Infected Flies. Vector Borne Zoonotic Dis 2008; 8:565-73. [DOI: 10.1089/vbz.2007.0223] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Satoru Konnai
- Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Hirohisa Mekata
- Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Raadan Odbileg
- Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Martin Simuunza
- Epidemiology Section, Disease Control Department, School of Veterinary Medicine, University of Zambia, Lusaka, Zambia
| | - Mwelwa Chembensof
- Epidemiology Section, Disease Control Department, School of Veterinary Medicine, University of Zambia, Lusaka, Zambia
| | - William Harold Witola
- Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Mwase Enala Tembo
- Epidemiology Section, Disease Control Department, School of Veterinary Medicine, University of Zambia, Lusaka, Zambia
| | - Harrison Chitambo
- Epidemiology Section, Disease Control Department, School of Veterinary Medicine, University of Zambia, Lusaka, Zambia
| | - Noboru Inoue
- National Research Centre for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Japan
| | - Misao Onuma
- Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Kazuhiko Ohashi
- Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
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