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Talenti A, Wilkinson T, Cook EA, Hemmink JD, Paxton E, Mutinda M, Ngulu SD, Jayaraman S, Bishop RP, Obara I, Hourlier T, Garcia Giron C, Martin FJ, Labuschagne M, Atimnedi P, Nanteza A, Keyyu JD, Mramba F, Caron A, Cornelis D, Chardonnet P, Fyumagwa R, Lembo T, Auty HK, Michaux J, Smitz N, Toye P, Robert C, Prendergast JGD, Morrison LJ. Continent-wide genomic analysis of the African buffalo (Syncerus caffer). Commun Biol 2024; 7:792. [PMID: 38951693 PMCID: PMC11217449 DOI: 10.1038/s42003-024-06481-2] [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: 12/28/2022] [Accepted: 06/21/2024] [Indexed: 07/03/2024] Open
Abstract
The African buffalo (Syncerus caffer) is a wild bovid with a historical distribution across much of sub-Saharan Africa. Genomic analysis can provide insights into the evolutionary history of the species, and the key selective pressures shaping populations, including assessment of population level differentiation, population fragmentation, and population genetic structure. In this study we generated the highest quality de novo genome assembly (2.65 Gb, scaffold N50 69.17 Mb) of African buffalo to date, and sequenced a further 195 genomes from across the species distribution. Principal component and admixture analyses provided little support for the currently described four subspecies. Estimating Effective Migration Surfaces analysis suggested that geographical barriers have played a significant role in shaping gene flow and the population structure. Estimated effective population sizes indicated a substantial drop occurring in all populations 5-10,000 years ago, coinciding with the increase in human populations. Finally, signatures of selection were enriched for key genes associated with the immune response, suggesting infectious disease exert a substantial selective pressure upon the African buffalo. These findings have important implications for understanding bovid evolution, buffalo conservation and population management.
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Affiliation(s)
- Andrea Talenti
- The Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, EH25 9RG, United Kingdom
- Centre for Tropical Livestock Genetics and Health (CTLGH), Roslin Institute, University of Edinburgh, Easter Bush Campus, Roslin, EH25 9RG, United Kingdom
| | - Toby Wilkinson
- The Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, EH25 9RG, United Kingdom
- Centre for Tropical Livestock Genetics and Health (CTLGH), Roslin Institute, University of Edinburgh, Easter Bush Campus, Roslin, EH25 9RG, United Kingdom
| | - Elizabeth A Cook
- International Livestock Research Institute, P.O. Box 30709, Nairobi, 00100, Kenya
- Centre for Tropical Livestock Genetics and Health (CTLGH), ILRI Kenya, P.O. Box 30709, Nairobi, 00100, Kenya
| | - Johanneke D Hemmink
- The Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, EH25 9RG, United Kingdom
- Centre for Tropical Livestock Genetics and Health (CTLGH), Roslin Institute, University of Edinburgh, Easter Bush Campus, Roslin, EH25 9RG, United Kingdom
- International Livestock Research Institute, P.O. Box 30709, Nairobi, 00100, Kenya
- Centre for Tropical Livestock Genetics and Health (CTLGH), ILRI Kenya, P.O. Box 30709, Nairobi, 00100, Kenya
| | - Edith Paxton
- The Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, EH25 9RG, United Kingdom
| | - Matthew Mutinda
- Kenya Wildlife Service, P.O. Box 40241, Nairobi, 00100, Kenya
| | | | - Siddharth Jayaraman
- The Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, EH25 9RG, United Kingdom
| | - Richard P Bishop
- International Livestock Research Institute, P.O. Box 30709, Nairobi, 00100, Kenya
| | - Isaiah Obara
- Institute for Parasitology and Tropical Veterinary Medicine, Freie Universität Berlin, Robert-von-Ostertag-Str. 7-13, 14163, Berlin, Germany
| | - Thibaut Hourlier
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire, CB10 1SD, United Kingdom
| | - Carlos Garcia Giron
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire, CB10 1SD, United Kingdom
| | - Fergal J Martin
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire, CB10 1SD, United Kingdom
| | | | | | - Anne Nanteza
- College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala, Uganda
| | - Julius D Keyyu
- Tanzania Wildlife Research Institute, Box 661, Arusha, Tanzania
| | - Furaha Mramba
- Vector and Vector-Borne Diseases Institute, Tanga, Tanzania
| | - Alexandre Caron
- ASTRE, University of Montpellier (UMR), CIRAD, 34090, Montpellier, France
- CIRAD, UMR ASTRE, RP-PCP, Maputo, 01009, Mozambique
- Faculdade Veterinaria, Universidade Eduardo Mondlan, Maputo, Mozambique
| | - Daniel Cornelis
- CIRAD, Forêts et Sociétés, 34398, Montpellier, France
- Forêts et Sociétés, University of Montpellier, CIRAD, 34090, Montpellier, France
| | | | - Robert Fyumagwa
- Tanzania Wildlife Research Institute, Box 661, Arusha, Tanzania
| | - Tiziana Lembo
- School of Biodiversity, One Health and Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Harriet K Auty
- School of Biodiversity, One Health and Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Johan Michaux
- Laboratoire de Génétique de la Conservation, Institut de Botanique (Bat. 22), Université de Liège (Sart Tilman), Chemin de la Vallée 4, B4000, Liège, Belgium
| | - Nathalie Smitz
- Royal Museum for Central Africa (BopCo), Leuvensesteenweg 13, 3080, Tervuren, Belgium
| | - Philip Toye
- International Livestock Research Institute, P.O. Box 30709, Nairobi, 00100, Kenya
- Centre for Tropical Livestock Genetics and Health (CTLGH), ILRI Kenya, P.O. Box 30709, Nairobi, 00100, Kenya
| | - Christelle Robert
- The Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, EH25 9RG, United Kingdom
- Centre for Tropical Livestock Genetics and Health (CTLGH), Roslin Institute, University of Edinburgh, Easter Bush Campus, Roslin, EH25 9RG, United Kingdom
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Cancer, University of Edinburgh, Crewe Road South, Edinburgh, EH4 2XU, United Kingdom
| | - James G D Prendergast
- The Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, EH25 9RG, United Kingdom
- Centre for Tropical Livestock Genetics and Health (CTLGH), Roslin Institute, University of Edinburgh, Easter Bush Campus, Roslin, EH25 9RG, United Kingdom
| | - Liam J Morrison
- The Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, EH25 9RG, United Kingdom.
- Centre for Tropical Livestock Genetics and Health (CTLGH), Roslin Institute, University of Edinburgh, Easter Bush Campus, Roslin, EH25 9RG, United Kingdom.
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Sajid MS, Iqbal A, Rizwan HM, Kausar A, Tahir UB, Younus M, Maqbool M, Siddique RM, Fouad D, Ataya FS. Guardians of the Herd: Molecular Surveillance of Tick Vectors Uncovers Theileriosis Perils in Large Ruminants. Microorganisms 2023; 11:2684. [PMID: 38004696 PMCID: PMC10672939 DOI: 10.3390/microorganisms11112684] [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: 09/26/2023] [Revised: 10/27/2023] [Accepted: 10/31/2023] [Indexed: 11/26/2023] Open
Abstract
Theileria sp. (Piroplasmida: Theileriidae) is one of the most widely known infections transmitted by hard ticks (Acari: Ixodidae) and has been linked to significant economic losses across the globe. The study's main emphasis was theileriosis, a disease that is common in Pakistan and has an incidence ranging from 0.6% to 33%. Through DNA screening of the vector ticks and host blood, this study sought to determine the risk of tick-borne theileriosis in populations of buffalos (Bubalus bubalis) and cattle (Bos indicus) in Toba Tek Singh district of Punjab, Pakistan. Identified tick species include Hyalomma anatolicum (35.4%), Rhipicephalus (Boophilus) microplus (30.2%), and R. sanguineus (25%). Tick specimens were collected from animals and their respective microenvironments. PCR assays targeting Theileria annulata were used to investigate the infection in the DNA extracted from the collected blood samples from large ruminants and salivary glands (SGs) of the Hyalomma ticks. The 18S rRNA of T. annulata was amplified using specific primers. Positive T. annulata amplicons were sequenced and verified using BLAST analysis. Overall, 50% of SGs contained T. annulate DNA. Female ticks, and those collected from cattle and from riverine environments had significantly higher (p < 0.05) rates of Theileria infection in their acini. Overall prevalence of Theileria infection was 35.9% in blood collected from large ruminants. Cattle had a substantially greater frequency of bovine theileriosis (43.2%) than buffalos (28.7%). Age and sex of large ruminants were significantly positively associated (p < 0.05) with Theileria infection. Furthermore, compared to non-riverine cattle (35%) and buffalo (19.5%), riverine cattle (52.2%) and buffalo (36.2%) showed a considerably higher prevalence. The results of this study, which is the first in Pakistan to examine the blood of large ruminants and vectorial function of Ixodid ticks in the transmission of T. annulata along with associated risk factors, offer an important insight for risk assessment of Theileria infection in livestock using vectorial infectivity.
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Affiliation(s)
- Muhammad Sohail Sajid
- Department of Parasitology, Faculty of Veterinary Science, University of Agriculture, Faisalabad 38000, Pakistan; (U.B.T.); (M.M.)
| | - Asif Iqbal
- Department of Parasitology, Riphah College of Veterinary Sciences, Lahore 54000, Pakistan; (A.I.); (R.M.S.)
| | - Hafiz Muhammad Rizwan
- Section of Parasitology, Department of Pathobiology, Khan Bahadur Chaudhary Mushtaq Ahmad College of Veterinary and Animal Sciences, Narowal, Sub Campus UVAS, Lahore 54000, Pakistan
| | - Asma Kausar
- Livestock and Dairy Development (L&DD), Veterinary Research Institute, Lahore 54080, Pakistan;
| | - Urfa Bin Tahir
- Department of Parasitology, Faculty of Veterinary Science, University of Agriculture, Faisalabad 38000, Pakistan; (U.B.T.); (M.M.)
- Department of Aquatic Animal Medicine, College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China
| | - Muhammad Younus
- Section of Pathology, Department of Pathobiology, Khan Bahadur Chaudhary Mushtaq Ahmad College of Veterinary and Animal Sciences, Narowal, Sub Campus UVAS, Lahore 54000, Pakistan;
| | - Mahvish Maqbool
- Department of Parasitology, Faculty of Veterinary Science, University of Agriculture, Faisalabad 38000, Pakistan; (U.B.T.); (M.M.)
| | - Rao Muhammad Siddique
- Department of Parasitology, Riphah College of Veterinary Sciences, Lahore 54000, Pakistan; (A.I.); (R.M.S.)
| | - Dalia Fouad
- Department of Zoology, College of Science, King Saud University, P.O. Box 22452, Riyadh 11459, Saudi Arabia;
| | - Farid Shokry Ataya
- Department of Biochemistry, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia;
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Mucheka VT, Pillay A, Mukaratirwa S. Prevalence of tick-borne pathogens in Rhipicephalus species infesting domestic animals in Africa: A systematic review and meta-analysis. Acta Trop 2023; 246:106994. [PMID: 37516420 DOI: 10.1016/j.actatropica.2023.106994] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Revised: 07/25/2023] [Accepted: 07/26/2023] [Indexed: 07/31/2023]
Abstract
Rhipicephalus ticks transmit important tick-borne pathogens (TBPs) such as Anaplasma, Babesia, and Theileria spp. which cause major economic losses in livestock production and contribute to emerging zoonotic diseases. A vast amount of data is available based on the demonstration of these pathogens in various host tissues, with limited information on the prevalence of these TBPs and their vectors. Quantifying TBPs infection rates among Rhipicephalus spp. is essential for the effective control and management of TBDs in domestic animals and surveillance of emerging diseases in humans, as they have close social associations. This review summarizes the prevalence of TBPs in Rhipicephalus spp. from domestic animals of Africa. A thorough search was done in SCOPUS, Web of Knowledge, PubMed, Google Scholar, and library sources from 2000 to 2022. All research in Africa reporting TBPs infection rates in Rhipicephalus spp. were included in the selection criteria. The meta-analysis evaluated publication bias using funnel plots to analyze the observed heterogeneity and applied a quality effects model. Prevalence estimates were based on data from 46 studies reporting TBPs infection rates in Rhipicephalus spp. from northern and sub-Saharan Africa. Sub-group analysis was done by geographic region and tick genus. A total of 12,368 Rhipicephalus spp. collected from domestic animals in Africa were used in the meta-analysis. The quality effects model revealed a high degree of heterogeneity among studies on the various TBPs. The overall prevalence of detected TBPs such as Theileria spp. was 8% (95% CI: 3-15%), Rickettsia spp. 3% (95% CI: 0-9%), Ehrlichia spp. 7% (95% CI: 2-14%), Anaplasma spp. 8% (95% CI: 2-16%), Coxiella spp. 10% (95% CI: 1-26%) and Babesia spp. 6% (95% CI: 2-12%). Northern Africa had the highest prevalence of Anaplasma spp. 12% (95% CI: 3-25%) and Theileria spp. 16% (95% CI: 0-42%). Whilst West Africa had the highest prevalence for Ehrlichia spp. 12% (95% CI: 3-24%) and eastern Africa for Rickettsia spp. 8% (95% CI: 4-12%). This is a systematic and quantitative investigation of the various TBPs detected in Rhipicephalus tick vectors from domestic animal hosts in Africa. The findings demonstrate considerable species variation across the African continent and offer preliminary estimates of infection rates for the continent.
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Affiliation(s)
- Vimbai Tendai Mucheka
- School of Life Sciences, Biological Sciences, College of Agriculture, Engineering and Science, University of KwaZulu-Natal, Westville Campus, Durban 4001, South Africa
| | - Alicia Pillay
- School of Life Sciences, Biological Sciences, College of Agriculture, Engineering and Science, University of KwaZulu-Natal, Westville Campus, Durban 4001, South Africa.
| | - Samson Mukaratirwa
- School of Life Sciences, Biological Sciences, College of Agriculture, Engineering and Science, University of KwaZulu-Natal, Westville Campus, Durban 4001, South Africa; One Health Centre for Zoonoses and Tropical Veterinary Medicine, Ross University School of Veterinary Medicine, Basseterre, St. Kitts, West Indies
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Day CA, Butler RA, Durick HE, Chandler JG, Paulsen DJ, Mordoh SL, Foggin C, Parry R, Moyo I, Russo L, Kennedy MA, Trout Fryxell RT. An ecological and epidemiological single-season survey of Anaplasma and Ehrlichia positive ticks in Victoria Falls National Park, Zimbabwe. MEDICAL AND VETERINARY ENTOMOLOGY 2023; 37:195-208. [PMID: 36695750 DOI: 10.1111/mve.12640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 12/21/2022] [Indexed: 05/18/2023]
Abstract
There is an urgent need for continued research on the ecology of tick-borne diseases in Africa. Our objective was to provide a preliminary description of the ecology and epidemiology of tick species, tick-borne pathogens, and animal hosts in Zimbabwe, focusing efforts at Victoria Falls National Park, for a single season. We tested the hypothesis that tick surveillance and pathogen screening data can be used to model associations among ticks, hosts, and pathogens. We collected ticks from domesticated animals and wildlife in Zimbabwe and screened the ticks for the presence of Anaplasma and Ehrlichia bacteria. Nearly 30% of the screened ticks were PCR-positive; 89% of tick species were PCR-positive, and 88% of animal species carried at least one PCR-positive tick. We sequenced a subset of amplicons that were similar to three Anaplasma species and three Ehrlichia species. The odds of a tick being PCR-positive increased when many ticks were collected from the host or the tick was collected from a cow (domesticated animal). Tick species shared host species more often than expected. We demonstrate that ticks in northwestern Zimbabwe present a One Health problem for nearby wildlife and humans.
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Affiliation(s)
- C A Day
- Department of Entomology and Plant Pathology, University of Tennessee, Knoxville, Tennessee, USA
| | - R A Butler
- Department of Entomology and Plant Pathology, University of Tennessee, Knoxville, Tennessee, USA
| | - H E Durick
- Center for Veterinary Medicine, University of Tennessee, Knoxville, Tennessee, USA
| | - J G Chandler
- Department of Entomology and Plant Pathology, University of Tennessee, Knoxville, Tennessee, USA
| | - David J Paulsen
- Department of Entomology and Plant Pathology, University of Tennessee, Knoxville, Tennessee, USA
| | - S L Mordoh
- Center for Veterinary Medicine, University of Tennessee, Knoxville, Tennessee, USA
| | - C Foggin
- Victoria Falls Wildlife Trust, Victoria Falls, Zimbabwe
| | - R Parry
- Victoria Falls Wildlife Trust, Victoria Falls, Zimbabwe
| | - I Moyo
- Victoria Falls Wildlife Trust, Victoria Falls, Zimbabwe
| | - L Russo
- Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, Tennessee, USA
| | - M A Kennedy
- Center for Veterinary Medicine, University of Tennessee, Knoxville, Tennessee, USA
| | - R T Trout Fryxell
- Department of Entomology and Plant Pathology, University of Tennessee, Knoxville, Tennessee, USA
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Ravindran R, Hembram PK, Kumar GS, Kumar KGA, Deepa CK, Varghese A. Transovarial transmission of pathogenic protozoa and rickettsial organisms in ticks. Parasitol Res 2023; 122:691-704. [PMID: 36797442 PMCID: PMC9936132 DOI: 10.1007/s00436-023-07792-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2022] [Accepted: 02/06/2023] [Indexed: 02/18/2023]
Abstract
Transovarial transmission (TOT) is an efficient vertical transmission of pathogens that is observed in many arthropod vectors. This method seems to be an evolutionarily unique development observed only in Babesia sensu stricto (clade VI) and Rickettsia spp., whereas transstadial transmission is the common/default way of transmission. Transovarial transmission does not necessarily contribute to the amplification of tick-borne pathogens but does contribute to the maintenance of disease in the environment. This review aims to provide an updated summary of previous reports on TOT of tick-borne pathogens.
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Affiliation(s)
- Reghu Ravindran
- Department of Veterinary Parasitology, College of Veterinary and Animal Sciences, Pookode, Wayanad, Kerala, 673 576, India.
| | - Prabodh Kumar Hembram
- Department of Veterinary Parasitology, College of Veterinary and Animal Sciences, Pookode, Wayanad, Kerala, 673 576, India
| | - Gatchanda Shravan Kumar
- Department of Veterinary Parasitology, College of Veterinary and Animal Sciences, Pookode, Wayanad, Kerala, 673 576, India
| | | | - Chundayil Kalarickal Deepa
- Department of Veterinary Parasitology, College of Veterinary and Animal Sciences, Pookode, Wayanad, Kerala, 673 576, India
| | - Anju Varghese
- Department of Veterinary Parasitology, College of Veterinary and Animal Sciences, Pookode, Wayanad, Kerala, 673 576, India
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Ergunay K, Mutinda M, Bourke B, Justi SA, Caicedo-Quiroga L, Kamau J, Mutura S, Akunda IK, Cook E, Gakuya F, Omondi P, Murray S, Zimmerman D, Linton YM. Metagenomic Investigation of Ticks From Kenyan Wildlife Reveals Diverse Microbial Pathogens and New Country Pathogen Records. Front Microbiol 2022; 13:932224. [PMID: 35847110 PMCID: PMC9283121 DOI: 10.3389/fmicb.2022.932224] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 05/27/2022] [Indexed: 11/13/2022] Open
Abstract
Focusing on the utility of ticks as xenosurveillance sentinels to expose circulating pathogens in Kenyan drylands, host-feeding ticks collected from wild ungulates [buffaloes, elephants, giraffes, hartebeest, impala, rhinoceros (black and white), zebras (Grévy’s and plains)], carnivores (leopards, lions, spotted hyenas, wild dogs), as well as regular domestic and Boran cattle were screened for pathogens using metagenomics. A total of 75 host-feeding ticks [Rhipicephalus (97.3%) and Amblyomma (2.7%)] collected from 15 vertebrate taxa were sequenced in 46 pools. Fifty-six pathogenic bacterial species were detected in 35 pools analyzed for pathogens and relative abundances of major phyla. The most frequently observed species was Escherichia coli (62.8%), followed by Proteus mirabilis (48.5%) and Coxiella burnetii (45.7%). Francisella tularemia and Jingmen tick virus (JMTV) were detected in 14.2 and 13% of the pools, respectively, in ticks collected from wild animals and cattle. This is one of the first reports of JMTV in Kenya, and phylogenetic reconstruction revealed significant divergence from previously known isolates and related viruses. Eight fungal species with human pathogenicity were detected in 5 pools (10.8%). The vector-borne filarial pathogens (Brugia malayi, Dirofilaria immitis, Loa loa), protozoa (Plasmodium spp., Trypanosoma cruzi), and environmental and water-/food-borne pathogens (Entamoeba histolytica, Encephalitozoon intestinalis, Naegleria fowleri, Schistosoma spp., Toxoplasma gondii, and Trichinella spiralis) were detected. Documented viruses included human mastadenovirus C, Epstein-Barr virus and bovine herpesvirus 5, Trinbago virus, and Guarapuava tymovirus-like virus 1. Our findings confirmed that host-feeding ticks are an efficient sentinel for xenosurveillance and demonstrate clear potential for wildlife-livestock-human pathogen transfer in the Kenyan landscape.
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Affiliation(s)
- Koray Ergunay
- Walter Reed Biosystematics Unit (WRBU), Smithsonian Institution Museum Support Center, Suitland, MD, United States
- One Health Branch, Walter Reed Army Institute of Research (WRAIR), Silver Spring, MD, United States
- Department of Medical Microbiology, Virology Unit, Faculty of Medicine, Hacettepe University, Ankara, Turkey
- Department of Entomology, Smithsonian Institution, National Museum of Natural History (NMNH), Washington, DC, United States
- *Correspondence: Koray Ergunay,
| | | | - Brian Bourke
- Walter Reed Biosystematics Unit (WRBU), Smithsonian Institution Museum Support Center, Suitland, MD, United States
- One Health Branch, Walter Reed Army Institute of Research (WRAIR), Silver Spring, MD, United States
- Department of Entomology, Smithsonian Institution, National Museum of Natural History (NMNH), Washington, DC, United States
| | - Silvia A. Justi
- Walter Reed Biosystematics Unit (WRBU), Smithsonian Institution Museum Support Center, Suitland, MD, United States
- One Health Branch, Walter Reed Army Institute of Research (WRAIR), Silver Spring, MD, United States
- Department of Entomology, Smithsonian Institution, National Museum of Natural History (NMNH), Washington, DC, United States
| | - Laura Caicedo-Quiroga
- Walter Reed Biosystematics Unit (WRBU), Smithsonian Institution Museum Support Center, Suitland, MD, United States
- One Health Branch, Walter Reed Army Institute of Research (WRAIR), Silver Spring, MD, United States
- Department of Entomology, Smithsonian Institution, National Museum of Natural History (NMNH), Washington, DC, United States
| | - Joseph Kamau
- One Health Centre, Institute of Primate Research (IPR), Nairobi, Kenya
| | - Samson Mutura
- One Health Centre, Institute of Primate Research (IPR), Nairobi, Kenya
| | | | - Elizabeth Cook
- International Livestock Research Institute (ILRI), Nairobi, Kenya
| | - Francis Gakuya
- Wildlife Research and Training Institute (WRTI), Naivasha, Kenya
| | - Patrick Omondi
- Wildlife Research and Training Institute (WRTI), Naivasha, Kenya
| | - Suzan Murray
- Global Health Program, Smithsonian Conservation Biology Unit, Fort Royal, VA, United States
| | - Dawn Zimmerman
- Walter Reed Biosystematics Unit (WRBU), Smithsonian Institution Museum Support Center, Suitland, MD, United States
- One Health Branch, Walter Reed Army Institute of Research (WRAIR), Silver Spring, MD, United States
- Department of Entomology, Smithsonian Institution, National Museum of Natural History (NMNH), Washington, DC, United States
- Department of Epidemiology of Microbial Disease, Yale School of Public Health, New Haven, CT, United States
| | - Yvonne-Marie Linton
- Walter Reed Biosystematics Unit (WRBU), Smithsonian Institution Museum Support Center, Suitland, MD, United States
- One Health Branch, Walter Reed Army Institute of Research (WRAIR), Silver Spring, MD, United States
- Department of Entomology, Smithsonian Institution, National Museum of Natural History (NMNH), Washington, DC, United States
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A Multi-copy Nucleic Acid-Based Diagnostic Test for Bovine Tropical Theileriosis. Acta Parasitol 2022; 67:504-510. [PMID: 34146240 DOI: 10.1007/s11686-021-00428-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Accepted: 05/25/2021] [Indexed: 10/21/2022]
Abstract
BACKGROUND Bovine tropical theileriosis (BTT) is a haemoprotozoan tick-borne disease that implicates huge losses to livestock in terms of considerable mortality and morbidity in tropical and subtropical regions of the globe. Currently available diagnostic methods have less specificity and sensitivity towards the detection of Theileria species. Therefore, an attempt was made to diagnose Theileria annulata by targeting a multi-copy gene, viz. mitochondrially encoded cytochrome b (MT-CYB) gene via polymerase chain reaction (PCR) in different agro-zones of India. METHODS AND RESULTS 129 cattle blood samples were collected from major livestock rearing regions of India and processed for both molecular and microscopic techniques. Screening of Giemsa-stained thin blood smears was able to detect 14 samples (10.85%) as positive for T. annulata. However, the MT-CYB gene-based PCR assay detected 107 samples (82.94%) positive for T. annulata out of 129 samples. Furthermore, the MT-CYB gene-based PCR assay was standardized in terms of its sensitivity and specificity. Specificity of PCR assay was evaluated against other common haemoprotozoan parasites of tropical countries viz. Babesia bigemina, Anaplasma marginale and Trypanosoma evansi. The multi-copy MT-CYB gene-based PCR assay provided an optimum level of sensitivity (up to the level of 10 femtogram) and high specificity. Haematological examination (Hb, PCV and TLC) of 113 samples revealed significantly (p < 0.05) decreased Hb and PCV levels in positive animals in comparison with the control group of healthy animals. However, the control group had significantly higher (p < 0.001) TLC levels than the positive group. CONCLUSION The MT-CYB gene-based PCR assay was found to be highly sensitive that can accurately detect the occurrence of T. annulata infection in carrier animals which are potential infection sources to healthier populations in naive demographic locations through infected ticks.
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Svitek N, Saya R, Zhang H, Nene V, Steinaa L. Systematic Determination of TCR–Antigen and Peptide–MHC Binding Kinetics among Field Variants of a Theileria parva Polymorphic CTL Epitope. THE JOURNAL OF IMMUNOLOGY 2022; 208:549-561. [PMID: 35031580 PMCID: PMC8802549 DOI: 10.4049/jimmunol.2100400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 11/23/2021] [Indexed: 11/24/2022]
Abstract
Positions 1–3 in the Tp9 CTL epitope are required for binding to BoLA-1*023:01. Positions 5–8 in the Tp9 epitope are required for TCR recognition in diverse CTLs. Tp9-specific CTLs from Muguga-immunized animals can cross-react with variants 4 and 7.
CTLs are known to contribute to immunity toward Theileria parva, the causative agent of East Coast fever. The Tp967–75 CTL epitope from the Muguga strain of T. parva is polymorphic in other parasite strains. Identifying the amino acids important for MHC class I binding, as well as TCR recognition of epitopes, can allow the strategic selection of Ags to induce cellular immunity toward T. parva. In this study, we characterized the amino acids important for MHC class I binding and TCR recognition in the Tp967–75 epitope using alanine scanning and a series of variant peptide sequences to probe these interactions. In a peptide–MHC class I binding assay, we found that the amino acids at positions 1, 2, and 3 were critical for binding to its restricting MHC class I molecule BoLA-1*023:01. With IFN-γ ELISPOT and peptide–MHC class I Tet staining assays on two parasite-specific bovine CTL lines, we showed that amino acids at positions 5–8 in the epitope were required for TCR recognition. Only two of eight naturally occurring polymorphic Tp9 epitopes were recognized by both CTLs. Finally, using a TCR avidity assay, we found that a higher TCR avidity was associated with a stronger functional response toward one of two variants recognized by the CTL. These data add to the growing knowledge on the cross-reactivity of epitope-specific CTLs and specificities that may be required in the selection of Ags in the design of a wide-spectrum vaccine for East Coast fever.
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Affiliation(s)
- Nicholas Svitek
- International Livestock Research Institute, Animal and Human Health Program, Nairobi, Kenya; and
| | - Rosemary Saya
- International Livestock Research Institute, Animal and Human Health Program, Nairobi, Kenya; and
| | - Houshuang Zhang
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Minhang District, Shanghai, China
| | - Vishvanath Nene
- International Livestock Research Institute, Animal and Human Health Program, Nairobi, Kenya; and
| | - Lucilla Steinaa
- International Livestock Research Institute, Animal and Human Health Program, Nairobi, Kenya; and
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9
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The Piroplasmida Babesia, Cytauxzoon, and Theileria in farm and companion animals: species compilation, molecular phylogeny, and evolutionary insights. Parasitol Res 2022; 121:1207-1245. [DOI: 10.1007/s00436-022-07424-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 01/02/2022] [Indexed: 12/13/2022]
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10
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Vimonish R, Dinkel KD, Fry LM, Johnson WC, Capelli-Peixoto J, Bastos RG, Scoles GA, Knowles DP, Madder M, Chaka G, Ueti MW. Isolation of infectious Theileria parva sporozoites secreted by infected Rhipicephalus appendiculatus ticks into an in vitro tick feeding system. Parasit Vectors 2021; 14:616. [PMID: 34952641 PMCID: PMC8704063 DOI: 10.1186/s13071-021-05120-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Accepted: 12/06/2021] [Indexed: 11/25/2022] Open
Abstract
Background Vector-borne diseases pose an increasing threat to global food security. Vaccines, diagnostic tests, and therapeutics are urgently needed for tick-borne diseases that affect livestock. However, the inability to obtain significant quantities of pathogen stages derived from ticks has hindered research. In vitro methods to isolate pathogens from infected tick vectors are paramount to advance transcriptomic, proteomic, and biochemical characterizations of tick-borne pathogens. Methods Nymphs of Rhipicephalus appendiculatus were infected with Theileria parva by feeding on a calf during an acute infection. Isolation of sporozoites was accomplished by feeding infected adult ticks on an in vitro tick feeding system. Sporozoite viability was tested using in vitro bovine lymphocytes. Results We isolated infectious T. parva sporozoites secreted into an in vitro tick feeding system. Infected adult R. appendiculatus ticks attached to and successfully fed on silicone membranes in the in vitro tick feeding system. Bovine blood in the receptacle was replaced with cell-free medium and the ticks were allowed to feed for 3 h to collect secreted T. parva sporozoites. Secreted sporozoites infected in vitro bovine lymphocytes, demonstrating that isolated sporozoites remained viable and infectious. Conclusions This work is the first to report the isolation of mature infectious T. parva sporozoites using an in vitro tick feeding system, which represents a significant step towards the development of a more efficient control strategy for T. parva. Isolation of infectious tick-stage parasites will facilitate the examination of the vector-pathogen interface, thereby accelerating the development of next-generation vaccines and treatment interventions for tick-borne pathogens. Graphical Abstract ![]()
Supplementary Information The online version contains supplementary material available at 10.1186/s13071-021-05120-7.
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11
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Allan FK, Jayaraman S, Paxton E, Sindoya E, Kibona T, Fyumagwa R, Mramba F, Torr SJ, Hemmink JD, Toye P, Lembo T, Handel I, Auty HK, Morrison WI, Morrison LJ. Antigenic Diversity in Theileria parva Populations From Sympatric Cattle and African Buffalo Analyzed Using Long Read Sequencing. Front Genet 2021; 12:684127. [PMID: 34335691 PMCID: PMC8320539 DOI: 10.3389/fgene.2021.684127] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 05/24/2021] [Indexed: 11/17/2022] Open
Abstract
East Coast fever (ECF) in cattle is caused by the Apicomplexan protozoan parasite Theileria parva, transmitted by the three-host tick Rhipicephalus appendiculatus. The African buffalo (Syncerus caffer) is the natural host for T. parva but does not suffer disease, whereas ECF is often fatal in cattle. The genetic relationship between T. parva populations circulating in cattle and buffalo is poorly understood, and has not been studied in sympatric buffalo and cattle. This study aimed to determine the genetic diversity of T. parva populations in cattle and buffalo, in an area where livestock co-exist with buffalo adjacent to the Serengeti National Park, Tanzania. Three T. parva antigens (Tp1, Tp4, and Tp16), known to be recognized by CD8+ and CD4+ T cells in immunized cattle, were used to characterize genetic diversity of T. parva in cattle (n = 126) and buffalo samples (n = 22). Long read (PacBio) sequencing was used to generate full or near-full length allelic sequences. Patterns of diversity were similar across all three antigens, with allelic diversity being significantly greater in buffalo-derived parasites compared to cattle-derived (e.g., for Tp1 median cattle allele count was 9, and 81.5 for buffalo), with very few alleles shared between species (8 of 651 alleles were shared for Tp1). Most alleles were unique to buffalo with a smaller proportion unique to cattle (412 buffalo unique vs. 231 cattle-unique for Tp1). There were indications of population substructuring, with one allelic cluster of Tp1 representing alleles found in both cattle and buffalo (including the TpM reference genome allele), and another containing predominantly only alleles deriving from buffalo. These data illustrate the complex interplay between T. parva populations in buffalo and cattle, revealing the significant genetic diversity in the buffalo T. parva population, the limited sharing of parasite genotypes between the host species, and highlight that a subpopulation of T. parva is maintained by transmission within cattle. The data indicate that fuller understanding of buffalo T. parva population dynamics is needed, as only a comprehensive appreciation of the population genetics of T. parva populations will enable assessment of buffalo-derived infection risk in cattle, and how this may impact upon control measures such as vaccination.
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Affiliation(s)
- Fiona K Allan
- Royal (Dick) School of Veterinary Studies, Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Siddharth Jayaraman
- Royal (Dick) School of Veterinary Studies, Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Edith Paxton
- Royal (Dick) School of Veterinary Studies, Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Emmanuel Sindoya
- Ministry of Livestock and Fisheries, Serengeti District Livestock Office, Mugumu, Tanzania
| | - Tito Kibona
- Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania
| | | | - Furaha Mramba
- Vector and Vector-Borne Diseases Research Institute, Tanga, Tanzania
| | - Stephen J Torr
- Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Johanneke D Hemmink
- Royal (Dick) School of Veterinary Studies, Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom.,International Livestock Research Institute, Nairobi, Kenya
| | - Philip Toye
- International Livestock Research Institute, Nairobi, Kenya
| | - Tiziana Lembo
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Ian Handel
- Royal (Dick) School of Veterinary Studies, Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Harriet K Auty
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - W Ivan Morrison
- Royal (Dick) School of Veterinary Studies, Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Liam J Morrison
- Royal (Dick) School of Veterinary Studies, Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
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12
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Maboko BB, Sibeko-Matjila KP, Pierneef R, Chan WY, Josemans A, Marumo RD, Mbizeni S, Latif AA, Mans BJ. South African Buffalo-Derived Theileria parva Is Distinct From Other Buffalo and Cattle-Derived T. parva. Front Genet 2021; 12:666096. [PMID: 34249088 PMCID: PMC8269612 DOI: 10.3389/fgene.2021.666096] [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: 02/09/2021] [Accepted: 05/27/2021] [Indexed: 11/13/2022] Open
Abstract
Theileria parva is a protozoan parasite transmitted by the brown-eared ticks, Rhipicephalus appendiculatus and Rhipicephalus zambeziensis. Buffaloes are the parasite's ancestral host, with cattle being the most recent host. The parasite has two transmission modes namely, cattle-cattle and buffalo-cattle transmission. Cattle-cattle T. parva transmission causes East Coast fever (ECF) and January disease syndromes. Buffalo to cattle transmission causes Corridor disease. Knowledge on the genetic diversity of South African T. parva populations will assist in determining its origin, evolution and identify any cattle-cattle transmitted strains. To achieve this, genomic DNA of blood and in vitro culture material infected with South African isolates (8160, 8301, 8200, 9620, 9656, 9679, Johnston, KNP2, HL3, KNP102, 9574, and 9581) were extracted and paired-end whole genome sequencing using Illumina HiSeq 2500 was performed. East and southern African sample data (Chitongo Z2, Katete B2, Kiambu Z464/C12, Mandali Z22H10, Entebbe, Nyakizu, Katumba, Buffalo LAWR, and Buffalo Z5E5) was also added for comparative purposes. Data was analyzed using BWA and SAMtools variant calling with the T. parva Muguga genome sequence used as a reference. Buffalo-derived strains had higher genetic diversity, with twice the number of variants compared to cattle-derived strains, confirming that buffaloes are ancestral reservoir hosts of T. parva. Host specific SNPs, however, could not be identified among the selected 74 gene sequences. Phylogenetically, strains tended to cluster by host with South African buffalo-derived strains clustering with buffalo-derived strains. Among the buffalo-derived strains, South African strains were genetically divergent from other buffalo-derived strains indicating possible geographic sub-structuring. Geographic sub- structuring was also observed within South Africa strains. The knowledge generated from this study indicates that to date, ECF is not circulating in buffalo from South Africa. It also shows that T. parva has historically been present in buffalo from South Africa before the introduction of ECF and was not introduced into buffalo during the ECF epidemic.
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Affiliation(s)
- Boitumelo B Maboko
- Agricultural Research Council, Onderstepoort Veterinary Research, Pretoria, South Africa.,Department of Veterinary Tropical Diseases, University of Pretoria, Pretoria, South Africa
| | | | - Rian Pierneef
- Agricultural Research Council, Biotechnology Platform, Pretoria, South Africa
| | - Wai Y Chan
- Agricultural Research Council, Biotechnology Platform, Pretoria, South Africa
| | - Antoinette Josemans
- Agricultural Research Council, Onderstepoort Veterinary Research, Pretoria, South Africa
| | - Ratselane D Marumo
- Agricultural Research Council, Onderstepoort Veterinary Research, Pretoria, South Africa
| | - Sikhumbuzo Mbizeni
- Agricultural Research Council, Onderstepoort Veterinary Research, Pretoria, South Africa.,Department of Agriculture and Animal Health, University of South Africa, Pretoria, South Africa
| | - Abdalla A Latif
- School of Life Sciences, University of KwaZulu Natal, Durban, South Africa
| | - Ben J Mans
- Agricultural Research Council, Onderstepoort Veterinary Research, Pretoria, South Africa.,Department of Veterinary Tropical Diseases, University of Pretoria, Pretoria, South Africa.,Department of Life and Consumer Sciences, University of South Africa, Pretoria, South Africa
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13
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Molecular detection of selected tick-borne pathogens infecting cattle at the wildlife-livestock interface of Queen Elizabeth National Park in Kasese District, Uganda. Ticks Tick Borne Dis 2021; 12:101772. [PMID: 34214889 DOI: 10.1016/j.ttbdis.2021.101772] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Revised: 04/19/2021] [Accepted: 06/03/2021] [Indexed: 11/22/2022]
Abstract
In Uganda, ticks and tick-borne diseases (TBDs) pose a big challenge to farmers. They reduce cattle productivity and cause severe economic damage. Several studies have documented the prevalence of tick-borne pathogens in cattle; however, their genetic characteristics and the role of wildlife-livestock interaction in the epidemiology of the TBDs are not well documented. This study assessed the prevalence and genetic diversity of various tick-borne pathogens (TBPs) as well as the risk factors associated with the occurrence of TBPs in blood samples of 208 randomly selected cattle from 16 farms located around Queen Elizabeth National Park (QENP) in Kasese District in western Uganda. Farming practices, disease challenges, and the level of wildlife-livestock interactions were assessed by a questionnaire survey amongst farm owners. Polymerase chain reaction (PCR) assays revealed that 62.9% (131/208) cattle samples were positive for one or more pathogens. Using specific PCR assays, we detected Theileria spp., Theileria parva, Anaplasma marginale, Anaplasma platys-like, and Babesia bigemina at 50.5%, 27.9%, 19.2%, 11.5% and 8.7%, respectively. We also confirmed the infection of samples by Theileria velifera and Theileria mutans after sequencing the Theileria spp. 18S rRNA gene. The risk factors associated with the occurrence of TBPs included communal grazing, herd size, age, and proximity to QENP. Phylogenetic analysis of the T. parva p104 gene showed a high identity to the previous isolates from Uganda and other East African countries and clustered closer to the buffalo (Syncerus caffer) isolates, suggesting a possible cross-species transmission. The sequences of A. marginale groEL and B. bigemina RAP-1a formed well-supported clades with high identities to the previous isolates identified from central and eastern Uganda. The isolates obtained from A. phagocytophilum 16S rRNA gene sequences showed relationship with A. platys-like, Anaplasma sp., uncultured Anaplasma species and A. phagocytophilum isolates from Africa, Asia, Europe, and the USA. The findings of the present study showed that TBDs are still a burden to farmers and that management practices in this area may increase the transmission of pathogens between livestock and wildlife.
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14
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Bawm S, Sagara R, Kakisaka K, Thu MJ, Hmoon MM, Htun LL, Win MM, Nonaka N, Nakao R, Suzuki H, Katakura K. Identification, genetic variation, and structural analysis of 18S rRNA of Theileria orientalis and Theileria velifera-like isolates from Myanmar. Parasitol Int 2021; 82:102299. [PMID: 33540120 DOI: 10.1016/j.parint.2021.102299] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 12/25/2020] [Accepted: 01/29/2021] [Indexed: 12/30/2022]
Abstract
Ribosomal RNA genes have been widely used for the identification and phylogenetic analysis of various organisms, including parasitic protozoa. Here, we report nine near full-length Theileria orientalis 18S rRNA gene sequences from cattle from different areas of Myanmar. Phylogenetic analysis of the 18S rRNA genes revealed a considerably close genetic relationship among T. orientalis isolates from Australia, China, Japan, Korea, Myanmar, and Pakistan. We also obtained four Theileria velifera-like (Theileria cf. velifera) 18S rRNA gene sequences from two cattle and two water buffaloes from the northernmost area of Myanmar. The phylogenetic analysis of T. cf. velifera isolates from Myanmar along with T. velifera and T. cf. velifera isolates from African countries suggested an evolutionary lineage of greater complexity in T. velifera-related parasites. DNA alignment analysis indicated the presence of 51 and 55 nucleotide variation positions within the 18S rRNA genes from 15 T. orientalis and 11 T. velifera-related isolates, respectively. Alignment entropy analysis of the 18S rRNA sequences indicated that both T. orientalis and T. velifera-related isolates had three hyper variable regions, corresponding to V2, V4, and V7 regions in eukaryotes. The degree of variation was prominent in the V2 in T. orientalis and V4 in T. velifera-related isolates. The secondary structure analysis of the 18S rRNA predicted using minimum free energy algorism revealed that the structure of V4 region differed most significantly between T. orientalis and T. velifera. These results provide novel insights into common structures, variations and functions of small subunit rRNA in Theileria species.
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Affiliation(s)
- Saw Bawm
- Department of Pharmacology and Parasitology, University of Veterinary Science, Yezin, Nay Pyi Taw 15013, Myanmar; Department of International Relations and Information Technology, University of Veterinary Science, Yezin, Nay Pyi Taw 15013, Myanmar
| | - Rumi Sagara
- Laboratory of Parasitology, Graduate School of Infectious Diseases, Faculty of Veterinary Medicine, Hokkaido University, Sapporo 060-0818, Japan
| | - Keita Kakisaka
- Laboratory of Parasitology, Graduate School of Infectious Diseases, Faculty of Veterinary Medicine, Hokkaido University, Sapporo 060-0818, Japan
| | - May June Thu
- Laboratory of Parasitology, Graduate School of Infectious Diseases, Faculty of Veterinary Medicine, Hokkaido University, Sapporo 060-0818, Japan
| | - Myint Myint Hmoon
- Department of Pharmacology and Parasitology, University of Veterinary Science, Yezin, Nay Pyi Taw 15013, Myanmar
| | - Lat Lat Htun
- Department of Pharmacology and Parasitology, University of Veterinary Science, Yezin, Nay Pyi Taw 15013, Myanmar
| | - Mar Mar Win
- Rector office, University of Veterinary Science, Yezin, Nay Pyi Taw, 15013, Myanmar
| | - Nariaki Nonaka
- Laboratory of Parasitology, Graduate School of Infectious Diseases, Faculty of Veterinary Medicine, Hokkaido University, Sapporo 060-0818, Japan
| | - Ryo Nakao
- Laboratory of Parasitology, Graduate School of Infectious Diseases, Faculty of Veterinary Medicine, Hokkaido University, Sapporo 060-0818, Japan
| | - Hitoshi Suzuki
- Laboratory of Ecology and Genetics, Graduate School of Environmental Science, Hokkaido University, Sapporo 060-0810, Japan
| | - Ken Katakura
- Laboratory of Parasitology, Graduate School of Infectious Diseases, Faculty of Veterinary Medicine, Hokkaido University, Sapporo 060-0818, Japan.
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15
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Mwamuye MM, Obara I, Elati K, Odongo D, Bakheit MA, Jongejan F, Nijhof AM. Unique Mitochondrial Single Nucleotide Polymorphisms Demonstrate Resolution Potential to Discriminate Theileria parva Vaccine and Buffalo-Derived Strains. Life (Basel) 2020; 10:life10120334. [PMID: 33302571 PMCID: PMC7764068 DOI: 10.3390/life10120334] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 12/07/2020] [Accepted: 12/08/2020] [Indexed: 11/18/2022] Open
Abstract
Distinct pathogenic and epidemiological features underlie different Theileria parva strains resulting in different clinical manifestations of East Coast Fever and Corridor Disease in susceptible cattle. Unclear delineation of these strains limits the control of these diseases in endemic areas. Hence, an accurate characterization of strains can improve the treatment and prevention approaches as well as investigate their origin. Here, we describe a set of single nucleotide polymorphisms (SNPs) based on 13 near-complete mitogenomes of T. parva strains originating from East and Southern Africa, including the live vaccine stock strains. We identified 11 SNPs that are non-preferentially distributed within the coding and non-coding regions, all of which are synonymous except for two within the cytochrome b gene of buffalo-derived strains. Our analysis ascertains haplotype-specific mutations that segregate the different vaccine and the buffalo-derived strains except T. parva-Muguga and Serengeti-transformed strains suggesting a shared lineage between the latter two vaccine strains. Phylogenetic analyses including the mitogenomes of other Theileria species: T. annulata, T. taurotragi, and T. lestoquardi, with the latter two sequenced in this study for the first time, were congruent with nuclear-encoded genes. Importantly, we describe seven T. parva haplotypes characterized by synonymous SNPs and parsimony-informative characters with the other three transforming species mitogenomes. We anticipate that tracking T. parva mitochondrial haplotypes from this study will provide insight into the parasite’s epidemiological dynamics and underpin current control efforts.
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Affiliation(s)
- Micky M. Mwamuye
- Institute for Parasitology and Tropical Veterinary Medicine, Freie Universität Berlin, Robert-von-Ostertag-Str. 7-13, 14163 Berlin, Germany; (I.O.); (K.E.)
- Correspondence: (M.M.M.); (A.M.N.); Tel.: +49-30-838-62326 (A.M.N.)
| | - Isaiah Obara
- Institute for Parasitology and Tropical Veterinary Medicine, Freie Universität Berlin, Robert-von-Ostertag-Str. 7-13, 14163 Berlin, Germany; (I.O.); (K.E.)
| | - Khawla Elati
- Institute for Parasitology and Tropical Veterinary Medicine, Freie Universität Berlin, Robert-von-Ostertag-Str. 7-13, 14163 Berlin, Germany; (I.O.); (K.E.)
| | - David Odongo
- School of Biological Sciences, University of Nairobi, P.O. Box 30197-00100 Nairobi, Kenya;
| | - Mohammed A. Bakheit
- Department of Parasitology, Faculty of Veterinary Medicine, University of Khartoum, P.O. Box 321-11115 Khartoum, Sudan;
| | - Frans Jongejan
- Vectors and Vector-Borne Diseases Research Programme, Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, 0110 Onderstepoort, South Africa;
| | - Ard M. Nijhof
- Institute for Parasitology and Tropical Veterinary Medicine, Freie Universität Berlin, Robert-von-Ostertag-Str. 7-13, 14163 Berlin, Germany; (I.O.); (K.E.)
- Correspondence: (M.M.M.); (A.M.N.); Tel.: +49-30-838-62326 (A.M.N.)
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16
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Squarre D, Nakamura Y, Hayashida K, Kawai N, Chambaro H, Namangala B, Sugimoto C, Yamagishi J. Investigation of the piroplasm diversity circulating in wildlife and cattle of the greater Kafue ecosystem, Zambia. Parasit Vectors 2020; 13:599. [PMID: 33256809 PMCID: PMC7708252 DOI: 10.1186/s13071-020-04475-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Accepted: 11/05/2020] [Indexed: 11/17/2022] Open
Abstract
Background Piroplasms are vector-borne intracellular hemoprotozoan parasites that infect wildlife and livestock. Wildlife species are reservoir hosts to a diversity of piroplasms and play an important role in the circulation, maintenance and evolution of these parasites. The potential for likely spillover of both pathogenic and non-pathogenic piroplasm parasites from wildlife to livestock is underlined when a common ecological niche is shared in the presence of a competent vector. Method To investigate piroplasm diversity in wildlife and the cattle population of the greater Kafue ecosystem, we utilized PCR to amplify the 18S rRNA V4 hyper-variable region and meta-barcoding strategy using the Illumina MiSeq sequencing platform and amplicon sequence variant (ASV)-based bioinformatics pipeline to generate high-resolution data that discriminate sequences down to a single nucleotide difference. Results A parasite community of 45 ASVs corresponding to 23 species consisting of 4 genera of Babesia, Theileria, Hepatozoon and Colpodella, were identified in wildlife and the cattle population from the study area. Theileria species were detected in buffalo, impala, hartebeest, sable antelope, sitatunga, wild dog and cattle. In contrast, Babesia species were only observed in cattle and wild dog. Our results demonstrate possible spillover of these hemoprotozoan parasites from wildlife, especially buffalo, to the cattle population in the wildlife-livestock interface. Conclusion We demonstrated that the deep amplicon sequencing of the 18S rRNA V4 hyper-variable region for wildlife was informative. Our results illustrated the diversity of piroplasma and the specificity of their hosts. They led us to speculate a possible ecological cycle including transmission from wildlife to domestic animals in the greater Kafue ecosystem. Thus, this approach may contribute to the establishment of appropriate disease control strategies in wildlife-livestock interface areas.![]()
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Affiliation(s)
- David Squarre
- Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan.,Wildlife Veterinary Unit, Department of National Parks and Wildlife, Chilanga, Zambia.,The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, UK
| | - Yukiko Nakamura
- Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan
| | - Kyoko Hayashida
- Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan.,International Collaboration Unit, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan
| | - Naoko Kawai
- Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan
| | - Herman Chambaro
- Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan.,Central Veterinary Research Institute, Ministry of Fisheries and Livestock, Chilanga, Zambia
| | - Boniface Namangala
- Department of Paraclinical Studies, University of Zambia, Lusaka, Zambia
| | - Chihiro Sugimoto
- Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan
| | - Junya Yamagishi
- Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan. .,International Collaboration Unit, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan.
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Anaplasma and Theileria Pathogens in Cattle of Lambwe Valley, Kenya: A Case for Pro-Active Surveillance in the Wildlife-Livestock Interface. Microorganisms 2020; 8:microorganisms8111830. [PMID: 33233713 PMCID: PMC7699859 DOI: 10.3390/microorganisms8111830] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Revised: 11/02/2020] [Accepted: 11/04/2020] [Indexed: 02/07/2023] Open
Abstract
Tick-borne pathogens (TBPs) are major constraints to livestock production and a threat to public health in Africa. This cross-sectional study investigated the risk of infection with TBPs in cattle of Lambwe Valley, Kenya. Blood samples of 680 zebu cattle from 95 herds in six geospatial clusters within 5 km of Ruma National Park were screened for bacterial and protozoan TBPs by high-resolution melting analysis and sequencing of PCR products. We detected Anaplasma bovis (17.4%), Anaplasma platys (16.9%), Anaplasma marginale (0.6%), Theileria velifera (40%), and Theileria mutans (25.7%), as well as an Anaplasma sp. (11.6%) that matched recently reported Anaplasma sp. sequences from Ethiopia. Babesia, Rickettsia, and Ehrlichia spp. were not detected. The animal and herd-level prevalences for TBPs were 78.5% (95% confidence intervals (CI): 75.3, 81.5) and 95.8% (95% CI: 91.8, 99.8), respectively. About 31.6% of cattle were co-infected with 13 combinations of TBPs. The prevalence of TBPs differed between clusters and age, but the risk of infection was not associated with sex, herd size, or the distance of homesteads from Ruma. This study adds insight into the epidemiology of TBPs around Ruma and highlights the need for proactive surveillance of TBPs in livestock–wildlife interfaces.
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18
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Capture-based enrichment of Theileria parva DNA enables full genome assembly of first buffalo-derived strain and reveals exceptional intra-specific genetic diversity. PLoS Negl Trop Dis 2020; 14:e0008781. [PMID: 33119590 PMCID: PMC7654785 DOI: 10.1371/journal.pntd.0008781] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2020] [Revised: 11/10/2020] [Accepted: 09/08/2020] [Indexed: 12/19/2022] Open
Abstract
Theileria parva is an economically important, intracellular, tick-transmitted parasite of cattle. A live vaccine against the parasite is effective against challenge from cattle-transmissible T. parva but not against genotypes originating from the African Cape buffalo, a major wildlife reservoir, prompting the need to characterize genome-wide variation within and between cattle- and buffalo-associated T. parva populations. Here, we describe a capture-based target enrichment approach that enables, for the first time, de novo assembly of nearly complete T. parva genomes derived from infected host cell lines. This approach has exceptionally high specificity and sensitivity and is successful for both cattle- and buffalo-derived T. parva parasites. De novo genome assemblies generated for cattle genotypes differ from the reference by ~54K single nucleotide polymorphisms (SNPs) throughout the 8.31 Mb genome, an average of 6.5 SNPs/kb. We report the first buffalo-derived T. parva genome, which is ~20 kb larger than the genome from the reference, cattle-derived, Muguga strain, and contains 25 new potential genes. The average non-synonymous nucleotide diversity (πN) per gene, between buffalo-derived T. parva and the Muguga strain, was 1.3%. This remarkably high level of genetic divergence is supported by an average Wright’s fixation index (FST), genome-wide, of 0.44, reflecting a degree of genetic differentiation between cattle- and buffalo-derived T. parva parasites more commonly seen between, rather than within, species. These findings present clear implications for vaccine development, further demonstrated by the ability to assemble nearly all known antigens in the buffalo-derived strain, which will be critical in design of next generation vaccines. The DNA capture approach used provides a clear advantage in specificity over alternative T. parva DNA enrichment methods used previously, such as those that utilize schizont purification, is less labor intensive, and enables in-depth comparative genomics in this apicomplexan parasite. An estimated 50 million cattle in sub-Saharan Africa are at risk of the deadly livestock disease East coast fever (ECF), caused by the parasite Theileria parva, which imposes tremendous economic hardship on smallholder farmers. An existing ECF vaccine protects against strains circulating among cattle, but not against T. parva derived from African Cape buffalo, its main wildlife carrier. Understanding this difference in protective efficacy requires characterization of the genetic diversity in T. parva strains associated with each mammalian host, a goal that has been hindered by the proliferation of T. parva in nucleated host cells, with much larger genomes. Here we adapted a sequence capture approach to target the whole parasite genome, enabling enrichment of parasite DNA over that of the host. Choices in protocol development resulted in nearly 100% parasite genome specificity and sensitivity, making this approach the most successful yet to generate T. parva genome sequence data in a high-throughput manner. The analyses uncovered a degree of genetic differentiation between cattle- and buffalo-derived genotypes that is akin to levels more commonly seen between species. This approach, which will enable an in-depth T. parva population genomics study from cattle and buffalo in the endemic regions, can easily be adapted to other intracellular pathogens.
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Agina OA, Shaari MR, Isa NMM, Ajat M, Zamri-Saad M, Hamzah H. Clinical Pathology, Immunopathology and Advanced Vaccine Technology in Bovine Theileriosis: A Review. Pathogens 2020; 9:E697. [PMID: 32854179 PMCID: PMC7558346 DOI: 10.3390/pathogens9090697] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Revised: 07/15/2020] [Accepted: 07/16/2020] [Indexed: 01/29/2023] Open
Abstract
Theileriosis is a blood piroplasmic disease that adversely affects the livestock industry, especially in tropical and sub-tropical countries. It is caused by haemoprotozoan of the Theileria genus, transmitted by hard ticks and which possesses a complex life cycle. The clinical course of the disease ranges from benign to lethal, but subclinical infections can occur depending on the infecting Theileria species. The main clinical and clinicopathological manifestations of acute disease include fever, lymphadenopathy, anorexia and severe loss of condition, conjunctivitis, and pale mucous membranes that are associated with Theileria-induced immune-mediated haemolytic anaemia and/or non-regenerative anaemia. Additionally, jaundice, increases in hepatic enzymes, and variable leukocyte count changes are seen. Theileria annulata and Theileria parva induce an incomplete transformation of lymphoid and myeloid cell lineages, and these cells possess certain phenotypes of cancer cells. Pathogenic genotypes of Theileria orientalis have been recently associated with severe production losses in Southeast Asia and some parts of Europe. The infection and treatment method (ITM) is currently used in the control and prevention of T. parva infection, and recombinant vaccines are still under evaluation. The use of gene gun immunization against T. parva infection has been recently evaluated. This review, therefore, provides an overview of the clinicopathological and immunopathological profiles of Theileria-infected cattle and focus on DNA vaccines consisting of plasmid DNA with genes of interest, molecular adjuvants, and chitosan as the most promising next-generation vaccine against bovine theileriosis.
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Affiliation(s)
- Onyinyechukwu Ada Agina
- Department of Veterinary Pathology and Microbiology, Faculty of Veterinary Medicine, Universiti Putra Malaysia, Serdang 43400, Malaysia;
- Department of Veterinary Pathology and Microbiology, Faculty of Veterinary Medicine, University of Nigeria Nsukka, Nsukka 410001, Nigeria
| | - Mohd Rosly Shaari
- Animal Science Research Centre, Malaysian Agricultural Research and Development Institute, Headquarters, Serdang 43400, Malaysia;
| | - Nur Mahiza Md Isa
- Department of Veterinary Pathology and Microbiology, Faculty of Veterinary Medicine, Universiti Putra Malaysia, Serdang 43400, Malaysia;
| | - Mokrish Ajat
- Department of Veterinary Pre-clinical sciences, Faculty of Veterinary Medicine, Universiti Putra Malaysia, Serdang 43400, Malaysia;
| | - Mohd Zamri-Saad
- Research Centre for Ruminant Diseases, Faculty of Veterinary Medicine, Universiti Putra Malaysia, Serdang 43400, Malaysia;
| | - Hazilawati Hamzah
- Department of Veterinary Pathology and Microbiology, Faculty of Veterinary Medicine, Universiti Putra Malaysia, Serdang 43400, Malaysia;
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Lubembe DM, Odongo DO, Salih DA, Sibeko-Matjila KP. Microsatellite and minisatellite genotyping of Theileria parva population from southern Africa reveals possible discriminatory allele profiles with parasites from eastern Africa. Ticks Tick Borne Dis 2020; 11:101539. [PMID: 32993948 DOI: 10.1016/j.ttbdis.2020.101539] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 07/20/2020] [Accepted: 07/30/2020] [Indexed: 10/23/2022]
Abstract
The control of Theileria parva, a protozoan parasite that threatens almost 50% of the cattle population in Africa, is still a challenge in many affected countries. Theileria parva field parasites from eastern Africa, and parasites comprising the current live T. parva vaccine widely deployed in the same region have been reported to be genotypically diverse. However, similar reports on T. parva parasites from southern Africa are limited, especially in Corridor disease designated areas. Establishing the extent of genetic exchange in T. parva populations is necessary for effective control of the parasite infection. Twelve polymorphic microsatellite and minisatellite loci were targeted for genotypic and population genetics analysis of T. parva parasites from South Africa, Mozambique, Kenya and Uganda using genomic DNA prepared from cattle and buffalo blood samples. The results revealed genotypic similarities among parasites from the two regions of Africa, with possible distinguishing allelic profiles on three loci (MS8, MS19 and MS33) for parasites associated with Corridor disease in South Africa, and East Coast fever in eastern Africa. Individual populations were in linkage equilibrium (VD<L), but when considered as one combined population, linkage disequilibrium (VD>L) was observed. Genetic divergence was observed to be more within (AMOVA = 74%) than between (AMOVA = 26%) populations. Principal coordinate analysis showed clustering that separated buffalo-derived from cattle-derived T. parva parasites, although parasites from cattle showed a close genetic relationship. The results also demonstrated geographic sub-structuring of T. parva parasites based on the disease syndromes caused in cattle in the two regions of Africa. These findings provide additional information on the genotypic diversity of T. parva parasites from South Africa, and reveal possible differences based on three loci (MS8, MS19 and MS33) and similarities between buffalo-derived T. parva parasites from southern and eastern Africa.
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Affiliation(s)
- Donald M Lubembe
- Vectors and Vector-borne Diseases Research Programme, Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, 0110, South Africa.
| | - David O Odongo
- School of Biological Sciences, University of Nairobi, P.O. Box 30197, Nairobi, 00100, Kenya
| | - Diaeldin A Salih
- Central Veterinary Research Laboratory, P.O. Box 8067, Khartoum, Sudan
| | - Kgomotso P Sibeko-Matjila
- Vectors and Vector-borne Diseases Research Programme, Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, 0110, South Africa
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Mukolwe LD, Odongo DO, Byaruhanga C, Snyman LP, Sibeko-Matjila KP. Analysis of p67 allelic sequences reveals a subtype of allele type 1 unique to buffalo-derived Theileria parva parasites from southern Africa. PLoS One 2020; 15:e0231434. [PMID: 32598384 PMCID: PMC7323972 DOI: 10.1371/journal.pone.0231434] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Accepted: 06/13/2020] [Indexed: 11/18/2022] Open
Abstract
East Coast fever (ECF) and Corridor disease (CD) caused by cattle- and buffalo-derived T. parva respectively are the most economically important tick-borne diseases of cattle in the affected African countries. The p67 gene has been evaluated as a recombinant subunit vaccine against ECF, and for discrimination of T. parva parasites causing ECF and Corridor disease. The p67 allele type 1 was first identified in cattle-derived T. parva parasites from East Africa, where parasites possessing this allele type have been associated with ECF. Subsequent characterization of buffalo-derived T. parva parasites from South Africa where ECF was eradicated, revealed the presence of a similar allele type, raising concerns as to whether or not allele type 1 from parasites from the two regions is identical. A 900 bp central fragment of the gene encoding p67 was PCR amplified from T. parva DNA extracted from blood collected from cattle and buffalo in South Africa, Mozambique, Kenya, Tanzania and Uganda, followed by DNA sequence analysis. Four p67 allele types previously described were identified. A subtype of p67 allele type 1 was identified in parasites from clinical cases of CD and buffalo from southern Africa. Notably, p67 allele type 1 sequences from parasites associated with ECF in East Africa and CD in Kenya were identical. Analysis of two p67 B-cell epitopes (TpM12 and AR22.7) revealed amino acid substitutions in allele type 1 from buffalo-derived T. parva parasites from southern Africa. However, both epitopes were conserved in allele type 1 from cattle- and buffalo-derived T. parva parasites from East Africa. These findings reveal detection of a subtype of p67 allele type 1 associated with T. parva parasites transmissible from buffalo to cattle in southern Africa.
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Affiliation(s)
- Lubembe D. Mukolwe
- Vectors and Vector-borne Diseases Research Programme, Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa
- Department of Veterinary Pathology, Microbiology & Parasitology, Faculty of Veterinary Medicine and Surgery, Egerton University, Egerton, Kenya
- * E-mail:
| | - David O. Odongo
- School of Biological Sciences, University of Nairobi, Nairobi, Kenya
| | - Charles Byaruhanga
- Vectors and Vector-borne Diseases Research Programme, Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa
- National Agricultural Research Organization, Entebbe, Uganda
| | - Louwtjie P. Snyman
- Vectors and Vector-borne Diseases Research Programme, Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa
- Durban Natural Science Museum, Durban, South Africa
| | - Kgomotso P. Sibeko-Matjila
- Vectors and Vector-borne Diseases Research Programme, Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa
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