Diagnostic methods used for the detection of Theileria equi: review of the last decade


  • Simona Giubega Banat’s University of Agricultural Sciences and Veterinary Medicine” King Michael I of Romania” from Timisoara
  • Cristian Dreghiciu Banat’s University of Agricultural Sciences and Veterinary Medicine” King Michael I of Romania” from Timisoara
  • Marius Stelian Ilie Banat’s University of Agricultural Sciences and Veterinary Medicine” King Michael I of Romania” from Timisoara
  • Gheorghe Darabus Banat’s University of Agricultural Sciences and Veterinary Medicine” King Michael I of Romania” from Timisoara




Theileria equi, equine piroplasmosis, PCR, cELISA, blood smear


Theileria equi is one of the aetiological agents responsible for EP and is transmitted by ticks to horses, mules, donkeys and zebras. Clinical signs are often nonspecific and can easily be confused with other pathologies. Although acute, sub-acute and chronic forms have been described, the most common situation in equines is that of asymptomatic carrier, characterized by undetectable or extremely low parasitaemia and lack of clinical signs. Identification of the parasitic agent can be done both by direct methods and by molecular and serological methods. This study aims to identify the most commonly used diagnostic methods of EP with the highest specificity and sensitivity and the fewest limitations. In order to achieve the aim of this study, a systematic database search was carried out, resulting, after a preliminary selection, in a total of 97 publications considered eligible. It was concluded that molecular diagnostic methods can overcome many of the limitations of traditional methods and are essential to identify and distinguish genotypes of T. equi. Nonmolecular diagnostic methods may lack sensitivity and specificity, but they are still widely used and useful to support clinical and epidemiological research.


Knowles, D.P.; Kappmeyer, L.S.; Haney, D.; Herndon, D.R.; Fry, L.M.; Munro, J.B.; Sears, K.; Ueti, M.V.; Wise, L.N; Silva, M.; Schneider, D.A.; Grause, J.; White, S.N.; Tretina, K.; Bishop, R.P.; Odongo, D.O.; Pelzel-McCluskey, A.M.; Scoles, G.A.; Mealey, R.H.; Silva, J.C. 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., 2018, 48(9-10):679-690.

Elsawy, B.S.M.; Nassar, A.M.; Alzan, H.F.; Bhoora, R.V.; Ozubek, S.; Mahmoud, M.S.; Kandil, O.M.; Mahdy, O.A. Rapid detection of equine piroplasms using multiplex PCR and first genetic characterization of Theileria haneyi in Egypt. Pathogens 2021, 10, 1414.

Phipps, L.P.; Otter, A. Transplacental transmission of Theileria equi in two foals born and reared in the United Kingdom. Vet Rec., 2004, 154:406–8.

Torres, R.; Hurtado, C.; Pérez-Macchi, S.; Bittencourt, P.; Freschi, C.; de Mello, V.V.C.; Machado, R.Z.; André, M.R.; Müller, A. Occurrence and Genetic Diversity of Babesia caballi and Theileria equi in Chilean Thoroughbred Racing Horses. Pathogens, 2021, 10(6):714.

OIE, Terrestrial Manual, Chapter 3.6.8, Equine Piroplasmosis, Available online: https://www.oie.int/fileadmin/Home/eng/Health_standards/tahm/3.06.08_EQUINE_PIROPLASMOSIS.pdf (accessed on 03.03.2022).

Wagner, G.; Cruz, D.; Holman, P.; Waghela, S.; Perrone, J.; Shompole, S.; Rurangirwa, F. Non-imunologic methods of diagnosis of babesiosis, Mem. Inst. Oswaldo Cruz, Rio de Janeiro, 1992, Vol. 87, Suppl III, 193-199

Oladosu, L. A.; Olufemi, B. E. Haematology of experimental babesiosis and ehrlichiosis in steroid immunosuppressed horses. Zentralblatt fur Veterinarmedizin. Reihe B. Journal of veterinary medicine, 1992, Series B, 39(5), 345–352.

De Waal, D. T.; Van Heerden, J.; Van den Berg, S. S.; Stegmann, G. F.; Potgieter, F. T. Isolation of pure Babesia equi and Babesia caballi organisms in splenectomized horses from endemic areas in South Africa. The Onderstepoort journal of veterinary research, 1988, 55(1), 33–35.

Lewis, M. J.; Wagner, B.; Woof, J. M. The different effector function capabilities of the seven equine IgG subclasses have implications for vaccine strategies. Molecular immunology, 2008, 45(3), 818–827.

https://vmrd.com/test-kits/detail/theileria-equi-antibody-test-kit-celisa/ (accessed on 23.02.2022).

Nardini, R.; Bartolomé Del Pino, L. E.; Cersini, A.; Manna, G.; Viola, M. R.; Antognetti, V.; Autorino, G. L.; Scicluna, M. T. Comparison of PCR-based methods for the detection of Babesia caballi and Theileria equi in field samples collected in Central Italy. Parasitology research, 2021, 120(6), 2157–2164.

McPherson, R.A.; Pincus, M. R. Henry's Clinical Diagnosis and Management by Laboratory Methods - Polymerase Chain Reaction and Other Nucleic Acid Amplification Technology, State University of New York Downstate Medical Center, Brooklyn, New York, 2022, (69) 1271-1281.

Chifiriuc, M. C.; Gheorghe, I.; Czobor, I.; Florea, D.A.; Mateescu, L.; Caplan, M.E.; Caplan, D. M; Lazar, V. Advances in molecular biology based assays for the rapid detection of food microbial contaminants, , Food Preservation, 2017.

Ferreira, E.P.; Vidotto, O.; Almeida, J.C.; Ribeiro, L.P.S.; Borges, M.V.; Pequeno, W.H.C.; Stipp, D.T.; de Oliveira, C.J.B.; Biondo, A.W.; Vieira, T.S.W.J.; et al. Serological and molecular detection of Theileria equi in sport horses of northeastern Brazil. Comp. Immunol. Microbiol. Infect. Dis. 2016, 47, 72–76

Butler, C. Can Theileria equi be eliminated from carrier horses? Vet. J. 2013, 196, 279.

Torres, R.; Hurtado, C.; Pérez-Macchi, S.; Bittencourt, P.; Freschi, C.; de Mello, V.V.C.; Machado, R.Z.; André, M.R.; Müller, A. Occurrence and Genetic Diversity of Babesia caballi and Theileria equi in Chilean Thoroughbred Racing Horses. Pathogens, 2021, 10(6):714.

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(1):459.

Onyiche, T.E.; Taioe, M.O.; Ogo, N.; Sivakumar, T.; Biu, A.A.; Mbaya, A.W.; 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, 2020,147(11):1238-1248.

Sunday Idoko I.; Tirosh-Levy S.; Leszkowicz M. M.; Mohammed A. B.; Sikiti G. B.; Wesley Nafarnda D.; Steinman A. Genetic Characterization of Piroplasms in Donkeys and Horses from Nigeria. Animals (Basel). 2020 Feb 18;10(2):324

Coultous, R.M.; McDonald, M.; Raftery, A.G.; Shiels, B.R.; Sutton, D.G.M.; Weir, W. Analysis of Theileria equi diversity in The Gambia using a novel genotyping method. Transbound Emerg Dis. 2020, 67(3):1213-1221.

Chisu, V.; Alberti, A.; Zobba, R.; Foxi, C.; Masala, G. Molecular characterization and phylogenetic analysis of Babesia and Theileria spp. in ticks from domestic and wild hosts in Sardinia. Acta Trop. 2019, 196:60-65.

Ybañez, A.P.; Ybañez, R.H.D.; Talle, M.G.; Arreglo, R.M.T.; Geens, M.J.C.; Villas, J.G.I. 3rd.; Villar, S.R.; Laruga, C.L.; Cao, S.; Moumouni, F.P.A.; Liu, M.; Igarashi, I.; Xuan, X. Serological and molecular detection of Theileria equi and Babesia caballi in Philippine horses. Ticks Tick Borne Dis. 2018, 9(5):1125-1128.

Lobanov, V.A.; Peckle, M.; Massard, C.L.; Brad Scandrett, W.; Gajadhar, A.A. Development and validation of a duplex real-time PCR assay for the diagnosis of equine piroplasmosis. Parasit Vectors. 2018, 11(1):125.

Vieira, M.; Costa, M. M.; de Oliveira, M. T.; Gonçalves, L. R.; André, M. R.; Machado, R. Z. Serological detection and molecular characterization of piroplasmids in equids in Brazil. Acta tropica, 2018, 179, 81–87.

Sumbria, D.; Singla, L.D.; Sharma, A.; Bal, M.S.; Randhawa, C.S. Molecular survey in relation to risk factors and haemato-biochemical alteration in Theileria equi infection of equines in Punjab Province, India. Vet Parasitol Reg Stud Reports. 2017, 8:43-50.

Malekifard, F.; Tavassoli, M.; Yakhchali, M.; Darvishzadeh, R. Detection of Theileria equi and Babesia caballi using mi-croscopic and molecular methods in horses in suburb of Urmia, Iran. Vet Res Forum. 2014, 5(2):129-33.

Alanazi, A.D.; Said, A.E.; Morin-Adeline, V.; Alyousif, M.S.; Slapeta, J. Quantitative PCR detection of Theileria equi using laboratory workflows to detect asymptomatic persistently infected horses. Vet Parasitol. 2014, 206(3-4):138-45.

Sebastian, P.S.; Benitez-Ibalo, A.P.; Flores, F.S.; Debárbora, V.N.; Martinez, E.I.; Thompson, C.S.; Mangold, A.J. Molec-ular detection and phylogenetic characterization of Theileria equi in horses (Equus caballus) from a peri-urban area of Argentina. Ticks Tick Borne Dis. 2021, 12(6):101810.

Romero-Salas, D.; Solis-Cortés. M.; Zazueta-Islas, H.M.; Flores-Vásquez, F.; Cruz-Romero, A.; Aguilar-Domínguez, M.; Salguero-Romero, J.L.; de León, A.P.; Fernández-Figueroa, E.A.; Lammoglia-Villagómez, M.Á.; Becker, I.; Sánchez-Montes, S. Molecular detection of Theileria equi in horses from Veracruz, Mexico. Ticks Tick Borne Dis. 2021, 12(3):101671.

Sears, K.P.; Kappmeyer, L.S.; Wise, L.N.; Silva, M.; Ueti, M.W.; White, S.; Reif, K.E.; Knowles, D.P. Infection dynamics of Theileria equi and Theileria haneyi, a newly discovered apicomplexan of the horse. Vet Parasitol. 2019, 271:68-75.

Allsopp, M.T.E.P.; Allsopp, B.A. Molecular sequence evidence for the reclassification of some Babesia species. Ann. N.Y. Acad. Sci. 2006, 1081, 509–517.

Peckle, M.; Pires, M.S.; Silva, C.B.D.; Costa, R.L.D.; Vitari, G.L.V.; Senra, M.V.X.; Dias, R.J.P.; Santos, H.A.; Massard, C.L. Molecular characterization of Theileria equi in horses from the state of Rio de Janeiro, Brazil. Ticks Tick Borne Dis. 2018, 9(2):349-353.

Gallusova, M.; Qablan, M. A.; D'Amico, G.; Obornik, M.; Petrzelkova, K. J.; Mihalca, A. D.; Modry, D. Piroplasms in feral and domestic equines in rural areas of the Danube Delta, Romania, with survey of dogs as a possible reservoir. Veterinary Parasitology, 2014, 206(3-4), 287-292.

Tirosh-Levy, S.; Gottlieb, Y.; Fry, L.M.; Knowles, D.P.; Steinman, A., Twenty Years of Equine Piroplasmosis Research: Global Distribution, Molecular Diagnosis, and Phylogeny. Pathogens 2020,9, 926.

Ribeiro, I.B.; Câmara, A.C.; Bittencourt, M.V.; Marçola, T.G.; Paludo, G.R.; Soto-Blanco, B. Detection of Theileria equi in spleen and blood of asymptomatic piroplasm carrier horses. Acta Parasitol. 2013, 58(2):218-22.

Camino, E.; Cruz-Lopez, F.; de Juan, L.; Dominguez, L.; Shiels, B.; Coultous, R.M. Phylogenetic analysis and geo-graphical distribution of Theileria equi and Babesia caballi sequences from horses residing in Spain. Ticks Tick Borne Dis. 2020, 11(6):101521.

Salinas-Estrella, E.; Ueti, M. W.; Lobanov, V. A.; Castillo-Payró, E.; Lizcano-Mata, A.; Badilla, C.; Martínez-Ibáñez, F.; Mosqueda, J. (Serological and molecular detection of Babesia caballi and Theileria equi in Mexico: A prospective study. PloS one, 2022, 17(3), e0264998.

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, 121(3):999-1008.

Bělková, T.; Bártová, E.; Řičařová, D.; Jahn, P.; Jandová, V.; Modrý, D.; Hrazdilová, K.; Sedlák, K. Theileria equi and Babesia caballi in horses in the Czech Republic. Acta Trop. 2021, 221:105993.

Coultous, R.M.; Leadon, D.P.; Shiels, B.R.; Sutton, D.; Weir W. Investigating the presence of equine piroplasmosis in Ireland. Veterinary Record. 2020, 187(11): e97.

Bartolomé Del Pino, L.E.; Nardini, R.; Veneziano, V.; Iacoponi, F.; Cersini, A.; Autorino, G.L.; Buono, F.; Scicluna, M. Babesia caballi and Theileria equi infections in horses in Central-Southern Italy: Sero-molecular survey and associated risk factors. Ticks Tick Borne Dis. 2016, 7(3):462-9.

Laus, F.; Spaterna, A.; Faillace, V.; Veronesi, F.; Ravagnan, S.; Beribé, F.; Cerquetella, M.; Meligrana, M.; Tesei, B. Clinical investigation on Theileria equi and Babesia caballi infections in Italian donkeys. BMC Veterinary Research, 2015, 11:100

Moretti, A.; Mangili, V.; Salvatori, R.; Maresca, C.; Scoccia, E.; Torina, A.; Moretta, I.; Gabrielli, S.; Tampieri, M.P.’ Pie-trobelli, M., Prevalence and diagnosis of Babesia and Theileria infections in horses in Italy: a preliminary study. Veter-inary Journal. 2010, 184(3):346-50.

Grandi, G.; Molinari, G.; Tittarelli, M.; Sassera, D.; Kramer, L.H. Prevalence of Theileria equi and Babesia caballi infection in horses from northern Italy, Vector Borne Zoonotic Dis. 2011, 11(7):955-6.

Butler, C. M.; Sloet van Oldruitenborgh-Oosterbaan, M. M.; Stout, T. A.; van der Kolk, J. H.; Wollenberg, L. V.; Nielen, M.; Jongejan, F.; Werners, A. H.; Houwers, D. J. Prevalence of the causative agents of equine piroplasmosis in the South West of The Netherlands and the identification of two autochthonous clinical Theileria equi infections. Veterinary journal, 2012, 193(2), 381–385.

Padalino, B.; Rosanowski, S. M.; Di Bella, C.; Lacinio, R.; Rubino, G. Piroplasmosis in Italian Standardbred Horses: 15 Years of Surveillance Data. Journal of equine veterinary science, 2019, 83, 102813.

Díaz-Sánchez, A. A.; Pires, M. S.; Estrada, C. Y.; Cañizares, E. V.; Del Castillo Domínguez, S. L.; Cabezas-Cruz, A.; Rivero, E. L.; da Fonseca, A. H.; Massard, C. L.; Corona-González, B. First molecular evidence of Babesia caballi and Theileria equi infections in horses in Cuba. Parasitology research, 2018, 117(10), 3109–3118.

Abedi, V.; Razmi, G.; Seifi, H.; Naghibi, A. Molecular detection of equine piroplasms in donkeys (Equus asinus) in North Khorasan province, Iran. Iranian journal of veterinary research, 2015, 16(2), 202–204.

Campos, J.; André, M. R.; Gonçalves, L. R.; Freschi, C. R.; Santos, F. M.; de Oliveira, C. E.; Piranda, E. M.; de Andrade, G. B.; Macedo, G. C.; Machado, R. Z.; Herrera, H. M. Assessment of equine piroplasmids in the Nhecolândia sub-region of Brazilian Pantanal wetland using serological, parasitological, molecular, and hematological approaches. Ticks and tick-borne diseases, 2019, 10(3), 714–721.

Nugraha, A. B.; Cahyaningsih, U.; Amrozi, A.; Ridwan, Y.; Agungpriyono, S.; Taher, D. M.; Guswanto, A.; Gantuya, S.; Tayebwa, D. S.; Tuvshintulga, B.; Sivakumar, T.; Yokoyama, N.; Igarashi, I. Serological and molecular prevalence of equine piroplasmosis in Western Java, Indonesia. Veterinary parasitology, regional studies and reports, 2018, 14, 1–6.

Souza, E.; Araujo, A. C.; Pires, L.; Freschi, C. R.; Azevedo, S. S.; Machado, R. Z.; Horta, M. C. Serological detection and risk factors for equine piroplasmosis in the semiarid region of Pernambuco, Northeastern Brazil, Brazilian journal of veterinary parasitology, 2019, 28(4), 685–691.




How to Cite

Giubega, S. (2022) “Diagnostic methods used for the detection of Theileria equi: review of the last decade”, Cluj Veterinary Journal, 27(2), pp. 16–24. doi: 10.52331/cvj.v27i2.37.

Most read articles by the same author(s)