Analyze Diet
Acta parasitologica2025; 70(2); 66; doi: 10.1007/s11686-025-01006-1

First Molecular Characterization of Theileria equi from Northeastern Algeria.

Abstract: Equine piroplasmosis (EP) is a tick-borne disease that affects equids and is caused by the parasites Theileria equi, Theileria haneyi and Babesia caballi. This disease leads to significant economic losses for the global equine industry. The current study aimed to evaluate the prevalence of Piroplasmida infections in equines from El Tarf, located in northeastern Algeria, and investigate the phylogenetic diversity within isolates obtained from infected equines in this study and between those from previous studies. Methods: A total of 120 blood samples were collected from equines in three municipalities of El Tarf. The small subunit of the 18 S rRNA gene, commonly used for genotyping and phylogenetic analysis, was amplified from the positive samples and subsequently sequenced for further analysis. Results: The study found that 40% of equines were infected with T. equi, while no cases of B. caballi infection were detected. The positivity rate was almost identical across all three municipalities. Four distinct T. equi 18 S rRNA gene sequences were identified in equines from El Tarf. Phylogenetic analysis revealed that these T. equi sequences could be categorized into three distinct clades. The isolates identified in this study grouped into clades A and C, indicating the presence of two genotypes of T. equi 18S rRNA sequences in El Tarf, Northeastern Algeria. Conclusions: The results confirmed a high prevalence of equine piroplasmosis in three municipalities of El Tarf. They also demonstrated that different isolates of T. equi can coexist within the same geographic region, offering additional insight into T. equi sequences. This finding emphasizes the significant implications for the surveillance of Apicomplexan parasites.
Publication Date: 2025-03-06 PubMed ID: 40050535PubMed Central: 6572709DOI: 10.1007/s11686-025-01006-1Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
  • Journal Article

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

Overview

  • This study investigated the presence and genetic diversity of the parasite Theileria equi in horses from northeastern Algeria, revealing a high infection rate and multiple genetic types coexisting in the region.

Introduction

  • Equine piroplasmosis (EP) is a disease affecting horses, donkeys, and related animals, caused mainly by Theileria equi, Theileria haneyi, and Babesia caballi.
  • EP is transmitted by ticks and has serious economic impact on the equine industry worldwide due to illness and loss of animal productivity.
  • The study aimed to assess how common Theileria equi infection is among equines in the El Tarf region of northeastern Algeria and to examine the genetic diversity of the parasite strains present.

Methods

  • A total of 120 blood samples were collected from equines across three municipalities within the El Tarf region.
  • Polymerase Chain Reaction (PCR) targeting the 18S rRNA gene—a genetic marker commonly used for identifying and classifying these parasites—was used to detect and genotype Theileria equi in positive samples.
  • Sequencing of the amplified 18S rRNA gene fragments enabled detailed genetic analysis and phylogenetic classification of the isolates.

Results

  • 40% of the tested equines were infected with Theileria equi, demonstrating a high prevalence of EP in the region.
  • No instances of Babesia caballi infection were found among the sampled animals.
  • The infection rate was consistent across the three municipalities studied, indicating widespread parasite presence in the entire area.
  • Four distinct genetic sequences of the T. equi 18S rRNA gene were identified in the infected horses from El Tarf.
  • Phylogenetic analysis grouped these sequences into three different clades (genetic clusters), with isolates from El Tarf falling into two of these clades, named A and C.
  • This shows that at least two different genotypes of T. equi coexist in this geographic region.

Conclusions

  • The study confirms a significant burden of equine piroplasmosis caused by T. equi in northeastern Algeria.
  • The coexistence of multiple genetic variants of T. equi within the same area has implications for disease monitoring, control strategies, and understanding parasite evolution.
  • The identification of distinct parasite genotypes provides valuable data that can improve epidemiological surveillance of apicomplexan parasites, the group to which Theileria belongs.
  • These insights may help in developing targeted interventions to reduce transmission and economic losses associated with equine piroplasmosis.

Cite This Article

APA
Sadeddine R, Righi S, Saidani K, Benakhla A. (2025). First Molecular Characterization of Theileria equi from Northeastern Algeria. Acta Parasitol, 70(2), 66. https://doi.org/10.1007/s11686-025-01006-1

Publication

ISSN: 1896-1851
NlmUniqueID: 9301947
Country: Switzerland
Language: English
Volume: 70
Issue: 2
Pages: 66

Researcher Affiliations

Sadeddine, Rima
  • Department, of Veterinary Science, Chadli Bendjedid University, El Tarf, 36000, Algeria. r.sadeddine@univ-eltarf.dz.
Righi, Souad
  • Department, of Veterinary Science, Chadli Bendjedid University, El Tarf, 36000, Algeria.
Saidani, Khelaf
  • Institute Veterinary Science, Saad Dahleb University, Blida, 9000, Algeria.
Benakhla, Ahmed
  • Department, of Veterinary Science, Chadli Bendjedid University, El Tarf, 36000, Algeria.

MeSH Terms

  • Animals
  • Theileria / genetics
  • Theileria / classification
  • Theileria / isolation & purification
  • Algeria / epidemiology
  • Horses
  • Theileriasis / epidemiology
  • Theileriasis / parasitology
  • Horse Diseases / parasitology
  • Horse Diseases / epidemiology
  • Phylogeny
  • RNA, Ribosomal, 18S / genetics
  • DNA, Protozoan / genetics
  • DNA, Protozoan / chemistry
  • Genotype
  • Prevalence
  • Babesiosis / epidemiology
  • Babesiosis / parasitology
  • Sequence Analysis, DNA
  • Genetic Variation
  • Babesia / genetics
  • Babesia / isolation & purification

Conflict of Interest Statement

Declarations. Competing Interests: The authors declare no competing interests.

References

This article includes 53 references
  1. Onyiche TE, Suganuma K, Igarashi I, Yokoyama N, Xuan X, Thekisoe O. A review on equine piroplasmosis: epidemiology, vector ecology, risk factors, host immunity, diagnosis and control.. Int J Environ Res Public Health 2019;16:1736.
    doi: 10.3390/ijerph16101736pubmed: 31100920pmc: 6572709google scholar: lookup
  2. Romero-Salas D, Solis-Cortés M, Zazueta-Islas HM, Flores-Vásquez F, Cruz-Romero A, Aguilar-Domínguez M, Salguero-Romero JL, de León AP, Fernández-Figueroa EA, Lammoglia-Villagómez MÁ. Molecular detection of Theileria equi in horses from Veracruz, Mexico.. Ticks Tick-Borne dis 2021;12:101671.
  3. Maslin J, Beugnet F, Davoust B, Klotz F. Babesiosis.. EMC -. Mal Infect 2004;1:281–292.
  4. Almazán C, Scimeca RC, Reichard MV, Mosqueda J. Babesiosis and theileriosis in North America.. Pathog Basel Switz 2022;11:168.
    doi: 10.3390/pathogens11020168google scholar: lookup
  5. Dahmana H, Amanzougaghene N, Davoust B, Normand T, Carette O, Demoncheaux J-P, Mulot B, Fabrizy B, Scandola P, Chik M. Great diversity of Piroplasmida in Equidae in Africa and Europe, including potential new species.. Vet Parasitol Reg Stud Rep 2019;18:100332.
  6. Silva MG, Graça T, Suarez CE, Knowles DP. Repertoire of Theileria equi immunodominant antigens bound by equine antibody.. Mol Biochem Parasitol 2013;188:109–115.
  7. 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.. Parasitol Res 2020;119:2955–2963.
    doi: 10.1007/s00436-020-06797-ypubmed: 32647992google scholar: lookup
  8. Scoles GA, Ueti MW. Vector ecology of equine piroplasmosis.. Annu Rev Entomol 2015;60:561–580.
  9. Leblond A. Equine piroplasmosis - the view of a practitioner from an endemic region.. Vet Rec 2019;184:92–94.
    doi: 10.1136/vr.l16pubmed: 30655402google scholar: lookup
  10. Wise LN, Pelzel-McCluskey AM, Mealey RH, Knowles DP. Equine piroplasmosis.. Vet. Clin. North am. Equine Pract 2014;30:677–693.
  11. Wise Ln, Kappmeyer Ls, Mealey Rh, Knowles D p. Review of equine piroplasmosis.. J Vet Intern Med 2013;27:1334–1346.
    doi: 10.1111/jvim.12168pubmed: 24033559google scholar: lookup
  12. 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;13:267.
    doi: 10.1186/s13071-020-04133-ypubmed: 32434550pmc: 7240905google scholar: lookup
  13. 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.. Pathog Basel Switz 2021;10:714.
    doi: 10.3390/pathogens10060714google scholar: lookup
  14. Coultous RM, Leadon DP, Shiels BR, Sutton D, Weir W. Investigating the presence of equine piroplasmosis in Ireland.. Vet Rec 2020;187:e97–e97.
    doi: 10.1136/vr.105937pubmed: 32887846google scholar: lookup
  15. Zhao S, Wang H, Zhang S, Xie S, Li H, Zhang X, Jia L. First report of genetic diversity and risk factor analysis of equine Piroplasm infection in equids in Jilin, China.. Parasit Vectors 2020;13:459.
    doi: 10.1186/s13071-020-04338-1pubmed: 32907616pmc: 7479743google scholar: lookup
  16. Alhassan A, Pumidonming W, Okamura M, Hirata H, Battsetseg B, Fujisaki K, Yokoyama N, Igarashi I. Development of a single-round and multiplex PCR method for the simultaneous detection of Babesia Caballi and Babesia equi in horse blood. Vet Parasitol 129:43–49.
    doi: 10.1016/j.vetpar.2004.12.018pubmed: 15817201google scholar: lookup
  17. Battsetseg B, Lucero S, Xuan X, Claveria FG, Inoue N, Alhassan A, Kanno T, Igarashi I, Nagasawa H, Mikami T. Detection of natural infection of Boophilus microplus with Babesia equi and Babesia Caballi in Brazilian horses using nested polymerase chain reaction. Vet Parasitol 107:351–357.
    doi: 10.1016/s0304-4017(02)00131-0pubmed: 12163246google scholar: lookup
  18. Salim B, Bakheit MA, Kamau J, Nakamura I, Sugimoto C. Nucleotide sequence heterogeneity in the small subunit ribosomal RNA gene within Theileria equi from horses in Sudan. Parasitol Res 106:493–498.
    doi: 10.1007/s00436-009-1691-7pubmed: 19953269google scholar: lookup
  19. Nagore D, García-Sanmartín J, García-Pérez AL, Juste RA, Hurtado A. Identification, genetic diversity and prevalence of Theileria and Babesia species in a sheep population from Northern Spain. Int J Parasitol 34:1059–1067.
    doi: 10.1016/j.ijpara.2004.05.008pubmed: 15313132google scholar: lookup
  20. Peckle M, Pires MS, Silva CB da, Costa RL da, Vitari GLV, Senra MVX, Dias RJP, Santos HA, Massard CL. Molecular characterization of Theileria equi in horses from the state of Rio de Janeiro, Brazil. Ticks Tick-Borne Dis 9:349–353.
    doi: 10.1016/j.ttbdis.2017.11.011pubmed: 29223587google scholar: lookup
  21. Roger MJ. Note On an Equine Piroplasma, Observed in Algeria. Vet. J. 1900 62, 362–364.
  22. Kouidri M, Ammar S, Kouider Z, Al-Abidine Z. First study on the composition species of tick (ixodidae) infesting horses in Algeria. Agricultura 109.
  23. Benfenatki A, Benfodil K, Miroud K, Zenia S, Khelef D, Ait-Oudhia K. Equine piroplasmosis in Northern Algeria: haematological and serological parameters. J Hell Vet Med Soc 73:3971–3978.
    doi: 10.12681/jhvms.25493google scholar: lookup
  24. Sadeddine R, Diarra AZ, Laroche M, Mediannikov O, Righi S, Benakhla A, Dahmana H, Raoult D, Parola P. Molecular identification of protozoal and bacterial organisms in domestic animals and their infesting ticks from north-eastern Algeria. Ticks Tick-Borne Dis 11:101330.
    doi: 10.1016/j.ttbdis.2019.101330pubmed: 31786146google scholar: lookup
  25. Kherifi W, Kherici-bousnoubra H. Analysis and correction of the rainfall records in some weather stations of the area of El Tarf (northeastern Algerian). LARHYSS J 14:153–165.
  26. Hall TA. BioEdit: a user-friendly biological sequence alignment editor and analysis program for Windows 95/98/NT. Nucleic acids symposium series (Oxford) pp. 95–98.
  27. Milne I, Wright F, Rowe G, Marshall DF, Husmeier D, McGuire G. TOPALi: software for automatic identification of Recombinant sequences within DNA multiple alignments. Bioinforma Oxf Engl 20:1806–1807.
  28. Benfenatki A, Bou N, Ait-Oudhia K, Khelef D. Prevalence of Theileria equi infection in Algiers urban area using cELISA and microscopic examination. Asian J Anim Vet Adv 11:511–515.
  29. Mahmoud MS, El-Ezz NTA, Abdel-Shafy S, Nassar SA, El Namaky AH, Khalil WKB, Knowles D, Kappmeyer L, Silva MG, Suarez CE. Assessment of Theileria equi and Babesia Caballi infections in equine populations in Egypt by molecular, serological and hematological approaches. Parasit Vectors 9:260.
    doi: 10.1186/s13071-016-1539-9pubmed: 27146413pmc: 4857240google scholar: lookup
  30. Jouglin M, Bonsergent clair, De la cotte N, Mège M, Bizon C, Couroucé A, Lallemand élodie-A, Leblond A, Lemonnier LC. Equine piroplasmosis in different geographical areas in France: prevalence heterogeneity of asymptomatic carriers and low genetic diversity of Theileria equi and Babesia Caballi. Ticks Tick-Borne Dis 16:102434.
    doi: 10.1016/j.ttbdis.2024.102434pubmed: 39754868google scholar: lookup
  31. Facile V, Magliocca M, Dini FM, Imposimato I, Mariella J, Freccero F, Urbani L, Rinnovati R, Sel E, Gallina L. Molecular diagnosis and identification of equine Piroplasms: challenges and insights from a study in Northern Italy. Animals 15(437).
    doi: 10.3390/ani15030437google scholar: lookup
  32. Camino E, Buendia A, Dorrego A, Pozo P, de Juan L, Dominguez L, Cruz-Lopez F. Sero-molecular survey and risk factors of equine piroplasmosis in horses in Spain. Equine Vet J 53:771–779.
    doi: 10.1111/evj.13348pubmed: 32918303google scholar: lookup
  33. Dhaouadi S, Mahjoub T, Drissi G, Bahri A, Mhadhbi M, Sassi L, Gharbi M. Epidemiological survey of vector-borne infections in equids from Northern Tunisia. Rev Sci Tech Int Off Epizoot 37:1021–1027.
    doi: 10.20506/rst.37.3.2904google scholar: lookup
  34. Ros-García A, M’ghirbi Y, Hurtado A, Bouattour A. Prevalence and genetic diversity of Piroplasm species in horses and ticks from Tunisia. Infect Genet Evol 17:33–37.
    doi: 10.1016/j.meegid.2013.03.038pubmed: 23542456google scholar: lookup
  35. Ferreira EP, Vidotto O, Almeida JC, Ribeiro LPS, Borges MV, Pequeno WHC, Stipp DT, de Oliveira CJB, Biondo AW, Vieira TSWJ. Serological and molecular detection of Theileria equi in sport horses of Northeastern Brazil. Comp Immunol Microbiol Infect Dis 47:72–76.
    doi: 10.1016/j.cimid.2016.06.004pubmed: 27477509google scholar: lookup
  36. Nugraha AB, Cahyaningsih U, Amrozi A, Ridwan Y, Agungpriyono S, Taher DM, Guswanto A, Gantuya S, Tayebwa DS, Tuvshintulga B. Serological and molecular prevalence of equine piroplasmosis in Western Java, Indonesia. Vet Parasitol Reg Stud Rep 14:1–6.
  37. Onyiche TE, Taioe MO, Ogo NI, Sivakumar T, Biu AA, Mbaya AW, Xuan X, Yokoyama N, Thekisoe O. Molecular evidence of Babesia Caballi and Theileria equi in equines and ticks in Nigeria: prevalence and risk factors analysis. Parasitology 147:1238–1248.
    doi: 10.1017/S0031182020000992pubmed: 32605687pmc: 10317755google scholar: lookup
  38. García-Bocanegra I, Arenas-Montes A, Hernández E, Adaszek Ł, Carbonero A, Almería S, Jaén-Téllez JA, Gutiérrez-Palomino P, Arenas A. Seroprevalence and risk factors associated with Babesia Caballi and Theileria equi infection in equids. Vet J 195:172–178.
    doi: 10.1016/j.tvjl.2012.06.012pubmed: 22784418google scholar: lookup
  39. Qablan MA, Oborník M, Petrželková KJ, Sloboda M, Shudiefat MF, Hořín P, Lukeš J, Modrý D. Infections by Babesia Caballi and Theileria equi in Jordanian equids: epidemiology and genetic diversity. Parasitology 140:1096–1103.
    doi: 10.1017/S0031182013000486pubmed: 23673249google scholar: lookup
  40. Roberts CW, Walker W, Alexander J. Sex-associated hormones and immunity to protozoan parasites. Clin Microbiol Rev 14:476–488.
    doi: 10.1128/CMR.14.3.476-488.2001pubmed: 11432809pmc: 88985google scholar: lookup
  41. Rüegg SR, Torgerson P, Deplazes P, Mathis A. Age-dependent dynamics of Theileria equi and Babesia Caballi infections in Southwest Mongolia based on IFAT and/or PCR prevalence data from domestic horses and ticks. Parasitology 134:939–947.
    doi: 10.1017/S0031182007002405pubmed: 17306055google scholar: lookup
  42. Moretti A, Mangili V, Salvatori R, Maresca C, Scoccia E, Torina A, Moretta I, Gabrielli S, Tampieri MP, Pietrobelli M. Prevalence and diagnosis of Babesia and theileria infections in horses in Italy: a preliminary study. Vet J Lond Engl 1997 184:346–350.
  43. Grandi G, Molinari G, Tittarelli M, Sassera D, Kramer LH. Prevalence of Theileria equi and Babesia Caballi infection in horses from Northern Italy. Vector Borne Zoonotic Dis Larchmt N 11:955–956.
    doi: 10.1089/vbz.2010.0193google scholar: lookup
  44. Bahrami S, Ghadrdan AR, Pourmahdi Borujeni M, Vafayi Salarpur M. Epidemiology of Theileria equi in Persian Arab horses from Iran. Veterinární Medicína 59:409–414.
    doi: 10.17221/7680-VETMEDgoogle scholar: lookup
  45. Salim BOM, Hassan SM, Bakheit MA, Alhassan A, Igarashi I, Karanis P, Abdelrahman MB. Diagnosis of Babesia Caballi and Theileria equi infections in horses in Sudan using ELISA and PCR. Parasitol Res 103:1145–1150.
    doi: 10.1007/s00436-008-1108-zpubmed: 18618143google scholar: lookup
  46. Kalantari M, Sharifiyazdi H, Ghaemi M, Ghane M, Nazifi S. Theileria equi in the horses of Iran: molecular detection, genetic diversity, and hematological findings. Vet Parasitol Reg Stud Rep 36:100792.
  47. Davitkov D, Davitkov D, Vucicevic M, Stanisic L, Radakovic M, Glavinic U, Stanimirovic Z. A molecular and haematological study of Theileria equi in Balkan donkeys. Acta Vet Hung 65:234–241.
    doi: 10.1556/004.2017.023pubmed: 28605963google scholar: lookup
  48. Bhoora R, Quan M, Franssen L, Butler CM, van der Kolk JH, Guthrie AJ, Zweygarth E, Jongejan F, Collins NE. Development and evaluation of real-time PCR assays for the quantitative detection of Babesia Caballi and Theileria equi infections in horses from South Africa. Vet Parasitol 168:201–211.
    doi: 10.1016/j.vetpar.2009.11.011pubmed: 20031328google scholar: lookup
  49. Ahedor B, Sivakumar T, Valinotti MFR, Otgonsuren D, Yokoyama N, Acosta TJ. PCR detection of Theileria equi and Babesia Caballi in apparently healthy horses in Paraguay. Vet Parasitol Reg Stud Rep 39:100835.
  50. 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. Pathog Basel Switz 10:1414.
    doi: 10.3390/pathogens10111414google scholar: lookup
  51. Nardini R, Bartolomé D, Pino LE, Cersini A, Manna G, Viola MR, Antognetti V, Autorino GL, Scicluna MT. Comparison of PCR-based methods for the detection of Babesia caballi and Theileria equi in field samples collected in Central Italy. Parasitol. Res. 120, 2157–2164.
  52. Bhoora R, Franssen L, Oosthuizen MC, Guthrie AJ, Zweygarth E, Penzhorn BL, Jongejan F, Collins NE. Sequence heterogeneity in the 18S rRNA gene within Theileria equi and Babesia Caballi from horses in South Africa. Vet Parasitol 159:112–120.
    doi: 10.1016/j.vetpar.2008.10.004pubmed: 19019541google scholar: lookup
  53. Ozubek S, Aktas M. Genetic diversity and prevalence of Piroplasm species in equids from Turkey. Comp Immunol Microbiol Infect Dis 59:47–51.
    doi: 10.1016/j.cimid.2018.08.005pubmed: 30290887google scholar: lookup

Citations

This article has been cited 1 times.
  1. Soliman AM, Elhawary NM, Helmy NM, El-Seify MA, Amer MM, Mohamed S, Memon FU, Rashid MHO, Gadelhaq SM. Molecular detection and genotyping of Theileria equi infection within the equine population in Giza, Egypt, using real-time PCR as compared with conventional detection methods.. Iran J Vet Res 2025;26(2):145-151.
    doi: 10.22099/ijvr.2025.51028.7553pubmed: 41170307google scholar: lookup