Discovery of a novel species, Theileria haneyi n. sp., infective to equids, highlights exceptional genomic diversity within the genus Theileria: implications for apicomplexan parasite surveillance.
Abstract: A novel apicomplexan parasite was serendipitously discovered in horses at the United States - Mexico border. Phylogenetic analysis based on 18S rDNA showed the erythrocyte-infective parasite to be related to, but distinct from, Theileria spp. in Africa, the most similar taxa being Theileria spp. from waterbuck and mountain zebra. The degree of sequence variability observed at the 18S rDNA locus also suggests the likely existence of additional cryptic species. Among described species, the genome of this novel equid Theileria parasite is most similar to that of Theileria equi, also a pathogen of horses. The estimated divergence time between the new Theileria sp. and T. equi, based on genomic sequence data, is greater than 33 million years. Average protein sequence divergence between them, at 23%, is greater than that of Theileria parva and Theileria annulata proteins, which is 18%. The latter two represent highly virulent Theileria spp. of domestic cattle, as well as of African and Asian wild buffalo, respectively, which differ markedly in pathology, host cell tropism, tick vector and geographical distribution. The extent of genome-wide sequence divergence, as well as significant morphological differences, relative to T. equi justify the classification of Theileria sp. as a new taxon. Despite the overall genomic divergence, the nine member equi merozoite antigen (EMA) superfamily, previously found as a multigene family only in T. equi, is also present in the novel parasite. Practically, significant sequence divergence in antigenic loci resulted in this undescribed Theileria sp. not being detectable using currently available diagnostic tests. Discovery of this novel species infective to equids highlights exceptional diversity within the genus Theileria, a finding with serious implications for apicomplexan parasite surveillance.
Published by Elsevier Ltd.
Publication Date: 2018-06-06 PubMed ID: 29885436DOI: 10.1016/j.ijpara.2018.03.010Google Scholar: Lookup
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- Journal Article
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- Non-U.S. Gov't
Summary
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A new species of apicomplexan parasite, distinct from but related to known Theileria species, was discovered in horses near the US-Mexico border. Phylogenetic analysis suggests additional similar undiscovered species may exist. Despite significant genomic divergence from known species, the study identified the presence of a nine-member superfamily common only to this and one other known Theileria species. This discrepancy renders the new species undetectable through standard diagnostic tests.
Discovery and Identification of New Parasite Species
- The study points out the discovery of a new species of apicomplexan parasite found in horses on the border between the United States and Mexico. This cannot be detected through standard diagnostic tests.
- This species, named Theileria haneyi, was identified as being related to but distinct from Theileria spp. in Africa.
- Phylogenetic analysis based on 18S rDNA showed it was quite similar to Theileria spp found in waterbucks and mountain zebras.
- However, the amount of sequence variability found at the 18S rDNA locus also implies the possibility of other undiscovered species.
Genomic Analysis of the Newly Discovered Species
- Comparing the genome of this new Theileria species to known species, it was found to be most similar to Theileria equi, another horse pathogen.
- The estimated time of divergence between this new species and T. equi exceeds 33 million years, suggesting an extensive evolutionary history.
- The protein sequence divergence between them is greater than that found between certain highly virulent Theileria spp of domestic cattle, demonstrating the distinctness of this new species.
Implications for Parasite Surveillance
- The discovery demonstrates the remarkable diversity within the genus Theileria, which could impact the strategies used for apicomplexan parasite surveillance.
- Given the significant sequence divergence in antigenic loci, current diagnostic tests will not detect this new Theileria species.
- The study underscores the need for continuous research and surveillance to identify and understand the spread of newly emerging pathogens.
Cite This Article
APA
Knowles DP, Kappmeyer LS, Haney D, Herndon DR, Fry LM, Munro JB, Sears K, Ueti MW, Wise LN, Silva M, Schneider DA, Grause J, White SN, Tretina K, Bishop RP, Odongo DO, Pelzel-McCluskey AM, Scoles GA, Mealey RH, Silva JC.
(2018).
Discovery of a novel species, Theileria haneyi n. sp., infective to equids, highlights exceptional genomic diversity within the genus Theileria: implications for apicomplexan parasite surveillance.
Int J Parasitol, 48(9-10), 679-690.
https://doi.org/10.1016/j.ijpara.2018.03.010 Publication
Researcher Affiliations
- Animal Disease Research Unit, Agricultural Research Service, United States Department of Agriculture, Pullman, WA, USA; Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, USA; The Paul G. Allen School for Global Animal Health, Washington State University, Pullman, WA, USA; Department of Comparative Medicine, University of Washington School of Medicine, Seattle, WA, USA. Electronic address: dknowles@wsu.edu.
- Animal Disease Research Unit, Agricultural Research Service, United States Department of Agriculture, Pullman, WA, USA.
- Animal and Plant Health Inspection Service, United States Department of Agriculture, Eagle Pass, TX, USA.
- Animal Disease Research Unit, Agricultural Research Service, United States Department of Agriculture, Pullman, WA, USA.
- Animal Disease Research Unit, Agricultural Research Service, United States Department of Agriculture, Pullman, WA, USA; Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, USA.
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD, USA. Electronic address: JMunro@som.umaryland.edu.
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, USA; Veterinary Clinical Sciences, Washington State University, Pullman, WA, USA.
- Animal Disease Research Unit, Agricultural Research Service, United States Department of Agriculture, Pullman, WA, USA; Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, USA; The Paul G. Allen School for Global Animal Health, Washington State University, Pullman, WA, USA.
- Department of Large Animal Medicine and Surgery, Physiology and Pharmacology, St. George's University School of Veterinary Medicine True Blue, St. George's, Grenada.
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, USA.
- Animal Disease Research Unit, Agricultural Research Service, United States Department of Agriculture, Pullman, WA, USA; Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, USA.
- Animal and Plant Health Inspection Service, National Veterinary Services Laboratories, United States Department of Agriculture, Ames, IA, USA.
- Animal Disease Research Unit, Agricultural Research Service, United States Department of Agriculture, Pullman, WA, USA; Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, USA.
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD, USA.
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, USA; The Paul G. Allen School for Global Animal Health, Washington State University, Pullman, WA, USA.
- Department of Zoology, Nairobi University, Nairobi, Kenya.
- Animal and Plant Health Inspection Service, Surveillance, Preparedness and Response Services, United States Department of Agriculture, Fort Collins, CO, USA.
- Animal Disease Research Unit, Agricultural Research Service, United States Department of Agriculture, Pullman, WA, USA.
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, USA.
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD, USA; Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, USA. Electronic address: jcsilva@som.umaryland.edu.
MeSH Terms
- Animals
- DNA, Protozoan / genetics
- Evolution, Molecular
- Female
- Genomics
- Horse Diseases / parasitology
- Horses
- Male
- Phylogeny
- RNA, Ribosomal, 18S / genetics
- Theileria / genetics
- Theileria / isolation & purification
- Theileria / pathogenicity
- Theileriasis / parasitology
- Virulence
Citations
This article has been cited 30 times.- Díaz-Sánchez AA, Obregón D, Santos HA, Corona-González B. Advances in the Epidemiological Surveillance of Tick-Borne Pathogens.. Pathogens 2023 Apr 23;12(5).
- Onzere CK, Hulbert M, Sears KP, Williams LBA, Fry LM. Tulathromycin and Diclazuril Lack Efficacy against Theileria haneyi, but Tulathromycin Is Not Associated with Adverse Clinical Effects in Six Treated Adult Horses.. Pathogens 2023 Mar 14;12(3).
- Ozubek S, Ulucesme MC, Aktas M. Discovery of a Novel Species Infecting Goats: Morphological and Molecular Characterization of Babesia aktasi n. sp.. Pathogens 2023 Jan 10;12(1).
- Mongruel ACB, Medici EP, da Costa Canena A, Calchi AC, Perles L, Rodrigues BCB, Soares JF, Machado RZ, André MR. Theileria terrestris nov. sp.: A Novel Theileria in Lowland Tapirs (Tapirus terrestris) from Two Different Biomes in Brazil.. Microorganisms 2022 Nov 23;10(12).
- Coultous R, Gotić J, McCann M, Sutton D, Beck R, Shiels B. Novel equi merozoite antigen (ema-1) gene heterogeneity in a geographically isolated Theileria equi population in Croatia.. Parasit Vectors 2022 Oct 31;15(1):401.
- Sivakumar T, Tuvshintulga B, Otgonsuren D, Batmagnai E, Ahedor B, Kothalawala H, Vimalakumar SC, Silva SSP, Yamagishi J, Yokoyama N. Phylogenetic analyses of the mitochondrial, plastid, and nuclear genes of Babesia sp. Mymensingh and its naming as Babesia naoakii n. sp.. Parasit Vectors 2022 Aug 24;15(1):299.
- Giubega S, Ilie MS, Luca I, Florea T, Dreghiciu C, Oprescu I, Morariu S, Dărăbuș G. Seroprevalence of Anti-Theileria equi Antibodies in Horses from Three Geographically Distinct Areas of Romania.. Pathogens 2022 Jun 9;11(6).
- Lv K, Zhang Y, Yang Y, Liu Z, Deng L. Development of Nested PCR and Duplex Real-Time Fluorescence Quantitative PCR Assay for the Simultaneous Detection of Theileria equi and Babesia caballi.. Front Vet Sci 2022;9:873190.
- Peckle M, Santos H, Pires M, Silva C, Costa R, Vitari G, Camilo T, Meireles N, Paulino P, Massard C. Dynamics of Theileria equi Infection in Rhipicephalus (Boophilus) microplus during the Parasitic Phase in a Chronically Infected Horse.. Pathogens 2022 Apr 29;11(5).
- Sears KP, Knowles DP, Fry LM. Clinical Progression of Theileria haneyi in Splenectomized Horses Reveals Decreased Virulence Compared to Theileria equi.. Pathogens 2022 Feb 16;11(2).
- Almazán C, Scimeca RC, Reichard MV, Mosqueda J. Babesiosis and Theileriosis in North America.. Pathogens 2022 Jan 27;11(2).
- Rocafort-Ferrer G, Leblond A, Joulié A, René-Martellet M, Sandoz A, Poux V, Pradier S, Barry S, Vial L, Legrand L. Molecular assessment of Theileria equi and Babesia caballi prevalence in horses and ticks on horses in southeastern France.. Parasitol Res 2022 Mar;121(3):999-1008.
- Schnittger L, Ganzinelli S, Bhoora R, Omondi D, Nijhof AM, Florin-Christensen M. The Piroplasmida Babesia, Cytauxzoon, and Theileria in farm and companion animals: species compilation, molecular phylogeny, and evolutionary insights.. Parasitol Res 2022 May;121(5):1207-1245.
- Chiuya T, Villinger J, Masiga DK, Ondifu DO, Murungi MK, Wambua L, Bastos ADS, Fèvre EM, Falzon LC. Molecular prevalence and risk factors associated with tick-borne pathogens in cattle in western Kenya.. BMC Vet Res 2021 Nov 27;17(1):363.
- Elsawy BSM, Nassar AM, Alzan HF, Bhoora RV, Ozubek S, Mahmoud MS, Kandil OM, Mahdy OA. Rapid Detection of Equine Piroplasms Using Multiplex PCR and First Genetic Characterization of Theileria haneyi in Egypt.. Pathogens 2021 Oct 31;10(11).
- Bonnet SI, Nadal C. Experimental Infection of Ticks: An Essential Tool for the Analysis of Babesia Species Biology and Transmission.. Pathogens 2021 Oct 29;10(11).
- Sundstrom KD, Lineberry MW, Grant AN, Duncan KT, Ientile MM, Little SE. Equine attachment site preferences and seasonality of common North American ticks: Amblyomma americanum, Dermacentor albipictus, and Ixodes scapularis.. Parasit Vectors 2021 Aug 14;14(1):404.
- Torres R, Hurtado C, Pérez-Macchi S, Bittencourt P, Freschi C, de Mello VVC, Machado RZ, André MR, Müller A. Occurrence and Genetic Diversity of Babesia caballi and Theileria equi in Chilean Thoroughbred Racing Horses.. Pathogens 2021 Jun 7;10(6).
- Idoko IS, Edeh RE, Adamu AM, Machunga-Mambula S, Okubanjo OO, Balogun EO, Adamu S, Johnson W, Kappmeyer L, Mousel M, Ueti MW. Molecular and Serological Detection of Piroplasms in Horses from Nigeria.. Pathogens 2021 Apr 23;10(5).
- Bastos RG, Sears KP, Dinkel KD, Kappmeyer L, Ueti MW, Knowles DP, Fry LM. Development of an Indirect ELISA to Detect Equine Antibodies to Theileria haneyi.. Pathogens 2021 Feb 27;10(3).
- Sears K, Knowles D, Dinkel K, Mshelia PW, Onzere C, Silva M, Fry L. Imidocarb Dipropionate Lacks Efficacy against Theileria haneyi and Fails to Consistently Clear Theileria equi in Horses Co-Infected with T. haneyi.. Pathogens 2020 Dec 10;9(12).
- Tirosh-Levy S, Gottlieb Y, Fry LM, Knowles DP, Steinman A. Twenty Years of Equine Piroplasmosis Research: Global Distribution, Molecular Diagnosis, and Phylogeny.. Pathogens 2020 Nov 8;9(11).
- Mshelia PW, Kappmeyer L, Johnson WC, Kudi CA, Oluyinka OO, Balogun EO, Richard EE, Onoja E, Sears KP, Ueti MW. Molecular detection of Theileria species and Babesia caballi from horses in Nigeria.. Parasitol Res 2020 Sep;119(9):2955-2963.
- Tirosh-Levy S, Steinman A, Levy H, Katz Y, Shtilman M, Gottlieb Y. Parasite load and genotype are associated with clinical outcome of piroplasm-infected equines in Israel.. Parasit Vectors 2020 May 20;13(1):267.
- Bishop RP, Kappmeyer LS, Onzere CK, Odongo DO, Githaka N, Sears KP, Knowles DP, Fry LM. Equid infective Theileria cluster in distinct 18S rRNA gene clades comprising multiple taxa with unusually broad mammalian host ranges.. Parasit Vectors 2020 May 19;13(1):261.
- Tirosh-Levy S, Gottlieb Y, Mimoun L, Mazuz ML, Steinman A. Transplacental Transmission of Theileria equi Is Not a Common Cause of Abortions and Infection of Foals in Israel.. Animals (Basel) 2020 Feb 21;10(2).
- Sunday Idoko I, Tirosh-Levy S, Leszkowicz Mazuz M, Mohammed Adam B, Sikiti Garba B, Wesley Nafarnda D, Steinman A. Genetic Characterization of Piroplasms in Donkeys and Horses from Nigeria.. Animals (Basel) 2020 Feb 18;10(2).
- Barbosa AD, Austen J, Portas TJ, Friend JA, Ahlstrom LA, Oskam CL, Ryan UM, Irwin PJ. Sequence analyses at mitochondrial and nuclear loci reveal a novel Theileria sp. and aid in the phylogenetic resolution of piroplasms from Australian marsupials and ticks.. PLoS One 2019;14(12):e0225822.
- Azmi K, Al-Jawabreh A, Abdeen Z. Molecular Detection of Theileria ovis and Theleiria equi in Livestock from Palestine.. Sci Rep 2019 Aug 9;9(1):11557.
- Tonui T, Corredor-Moreno P, Kanduma E, Njuguna J, Njahira MN, Nyanjom SG, Silva JC, Djikeng A, Pelle R. Transcriptomics reveal potential vaccine antigens and a drastic increase of upregulated genes during Theileria parva development from arthropod to bovine infective stages.. PLoS One 2018;13(10):e0204047.
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