Theileria equi is a protozoan parasite that infects horses, causing a disease known as equine piroplasmosis. This parasite is transmitted primarily through tick bites, with species such as Rhipicephalus and Dermacentor acting as vectors. The infection can lead to a range of clinical signs in horses, including fever, anemia, jaundice, and lethargy. Infected horses may also exhibit decreased performance and, in severe cases, death. Diagnosis of Theileria equi involves blood tests, including polymerase chain reaction (PCR) assays and serological methods, to detect the presence of the parasite or antibodies. This page compiles peer-reviewed research studies and scholarly articles that explore the transmission, pathogenesis, diagnosis, and management of Theileria equi in equine populations.
El-Sayed SAE, AbouLaila M, ElKhatam A, Abdel-Wahab A, Rizk MA.In the present study, we conducted an epidemiological survey of Theileria equi, with sequencing analysis of the PCR product using blood-DNA samples collected from donkeys (n = 149) reared in different Egyptian provinces in Lower Egypt (Menoufia and Mersa Matruh) and middle Egypt (Giza). All animals were tested for the presence of T. equi parasite using species-specific PCR assay targeting the Equi merozoite antigen-1 (EMA-1). Nine- (6.04%) samples were positive for T. equi. The highest positive rate for infection was detected in Giza zoological garden (10.16%). Egyptian EMA-1 gene sequence e...
Onyiche TE, Taioe MO, Molefe NI, Biu AA, Luka J, Omeh IJ, Yokoyama N, Thekisoe O.Equine piroplasmosis (EP) is a tick-borne disease of economic importance, relevant in the international movement of equids. The causative agents are at least two apicomplexan protozoan parasites Babesia caballi and Theileria equi. To date, there is no study that estimates global and regional exposure of equids to EP. We therefore conducted a systematic review and meta-analysis to estimate the pooled prevalence and heterogeneity of EP using random-effects model. Six electronic databases were searched for publications on EP and assessed according to Preferred Reporting Items for Systematic Revie...
Camino E, Cruz-Lopez F, de Juan L, Dominguez L, Shiels B, Coultous RM.The intraerythrocytic protozoans Theileria equi and Babesia caballi are the causative agents of equine piroplasmosis (EP), one of the most important equine tick-borne diseases due to its significant impact on global international horse trade. Although EP is known to be endemic in Spain, previous phylogenetic studies have only been conducted for limited geographical regions. Therefore, the objective of this study was to evaluate the genetic diversity and distribution of these parasite species nationwide. This was performed by amplification of the 18S small subunit (SSU) rRNA gene from 100 EP ...
Mahmoud MS, Kandil OM, Abu El-Ezz NT, Hendawy SHM, Elsawy BSM, Knowles DP, Bastos RG, Kappmeyer LS, Laughery JM, Alzan HF, Suarez CE.The tick-borne intra-erythrocytic apicomplexan Babesia caballi is one of the etiological agents of equine babesiosis, an economically important disease of equids in most tropical and subtropical areas of the world. Discovering candidate antigens for improved diagnostic tools and vaccines remains needed for controlling equine babesiosis. This study describes the B. caballi sbp4 (Bcsbp4) gene and protein (BcSBP4) and analyzes its antigenicity in infected equids. Methods: BLAST searches of an uncurated B. caballi assembly genome using the B. bovis SBP4 as a query were carried out, followed by PCR...
Tirosh-Levy S, Gottlieb Y, Mazuz ML, Savitsky I, Steinman A.The tick-borne equine hemoparasite, Theileria equi, is endemic in many parts of the world where prevalence may be high, and most infected horses are apparently healthy but serve as life-long carriers. To determine the factors that affect T. equi dynamics, we followed parasitic loads in apparently healthy horses at four time points during one year. A total of 1094 blood samples were collected from 395 horses, along with ticks and demographic and clinical data. Infection and load of T. equi were tested by PCR and qPCR, and for the spring dataset, infection was also tested serologically by IFAT (...
Mshelia PW, Kappmeyer L, Johnson WC, Kudi CA, Oluyinka OO, Balogun EO, Richard EE, Onoja E, Sears KP, Ueti MW.Equine piroplasmosis (EP) is an infectious, tick-borne disease caused by the hemoprotozoan parasites, Theileria equi, Babesia caballi, and a recently reported new species, T. haneyi. Infections by these apicomplexan parasites limit performance and cause economic losses for the horse industry. Equine piroplasmosis is widespread in the northern regions of Nigeria, where an increasing portion of the animal population is composed of horses. This disease has remained epidemiologically challenging, especially as the movement of horses increases across Nigeria. In this study, blood samples from 300 h...
Hao L, Yuan D, Li S, Jia T, Guo L, Hou W, Lu Z, Mo X, Yin J, Yang A, Zheng W, Li R.Theileria species, with a broad geographic distribution, infect a wide range of both domestic and wild animals and are transmitted by ixodid ticks. Currently, there is no comprehensive report regarding the distribution of Theileria spp. in the eastern Tibetan Plateau, especially in Ganze Tibetan autonomous prefecture (153,700 km) and Ngawa Tibetan and Qiang autonomous prefecture (84,242 km) of Sichuan province, China. In this study, we collected blood samples from yaks (n = 144) (Bos grunniens), Tibetan sheep (n = 92), and Tibet horses (n = 142) in Ganze and Ngawa.Theileria sinen...
Onyiche TE, Taioe MO, Ogo NI, Sivakumar T, Biu AA, Mbaya AW, Xuan X, Yokoyama N, Thekisoe O.Babesia caballi and Theileria equi are biological agents responsible for equine piroplasmosis (EP). We conducted a robust and extensive epidemiological study in Nigeria on the prevalence and risk factors of EP. Blood (468, both horses and donkeys) and ticks (201 pools) were screened using polymerase chain reaction (PCR). DNA of equine piroplasms was observed in tick pools with B. caballi amplified in Rhipicephalus evertsi evertsi only [minimum infection rate (MIR) of 7.6%] while T. equi was observed in R. e. evertsi (MIR, 61.6%), Hyalomma dromedarii (MIR, 23.7%) and H. truncatum (MIR, 50.0%). ...
Shah MH, Ijaz M, Ahmed A, Aziz MU, Ghaffar A, Ghauri HN, Naveed M.Theileriosis is an important disease of economic significance which badly affects the equine husbandry of developing countries. The present study was planned to investigate the molecular prevalence of theileriosis, associated risk factors, and alterations in hematological parameters of donkeys and mules from district Mianwali, Punjab, Pakistan. Blood samples from 150 equids (n = 75 donkeys; n = 75 mules) were examined microscopically, and the genomic DNA from each sample was processed for the amplification of the 18S rRNA gene of Theileria. The polymerase chain reaction confirmed isolates we...
Wang Y, Zhang LP, Li J, Li DD, Zhang Q, Li C.The aim of this study was to determine the seroprevalence of Babesia caballi and Theileria equi in horses imported into Shanghai port. Between 2018 and 2019, 344 horse sera samples were collected and tested for B. caballi and T. equi, using commercially available kits. Only one B. caballi seropositive sample was detected. To the best of our knowledge, this is the first report of a B. caballi seropositive in imported horses at Shanghai port, which reflects the importance of monitoring piroplasmosis seroprevalence in imported horses.
Babesia caballi and Theileria equi are widely recognized as causative agents of equine pirolasmosis (EP), an acute, sub-acute, and chronic disease of equines, with relevant economic impact on horse trade worldwide. Although several studies on EP prevalence from central Italy have been published, data on ticks responsible for its transmission are still lacking. In this study, we identified a potential competent vector, investigating main features of its ecology together with EP infection rates. A two-year sampling of questing ticks was carried out for the first time in Italy in an area known fo...
Ahmadpour S, Esmaeilnejad B, Dalir-Naghadeh B, Asri-Rezaei S.Equine theileriosis due to Theileria equi is probably the most widespread and pathogenic disease of equines, which comes with major cardiac and renal complications. This study was undertaken to investigate the biomarkers of cardiac and renal functions in horses infected with T. equi and determine the association between these parameters and the level of parasitemia. Giemsa-stained blood smears from 300 horses with ages of 3-4 years old were examined for detection of T. equi on erythrocytes. Moreover, multiplex PCR was employed for confirmation of the diagnosis in the 28 positive cases. Based o...
Ahmadi Afshar N, Malekifard F, Asri Rezaei S, Tavassoli M.Equine piroplasmosis is a tick-borne protozoal disease affecting horses, mules, donkeys and zebras and can lead to severe economic losses in the equine industry. There is limited information on clinical pathologic changes of equine piroplasmosis in donkeys. This study aims to investigate the impacts of babesiosis on various hematological and biochemical properties in naturally infected donkeys with Theileria equi and Babesia caballi. Methods: A total of 200 apparently healthy donkeys were randomly examined for the presence of equine piroplasmosis in blood samples. Of 200 samples, 11(5.5%) anim...
Tirosh-Levy S, Steinman A, Levy H, Katz Y, Shtilman M, Gottlieb Y.Equine piroplasmosis is a highly endemic protozoan disease of horses worldwide, caused by Theileria equi and Babesia caballi. While most horses in endemic areas are subclinically infected, the mechanisms leading to clinical outcome are vastly unknown. Moreover, since clinical signs of disease are not specific, and the prevalence in endemic areas is high, it is difficult to determine if equine piroplasmosis is the cause of disease. To identify possible mechanisms leading to the clinical outcome in an endemic area, we compared parasite loads and genotypes in clinically and subclinically infected...
Bishop RP, Kappmeyer LS, Onzere CK, Odongo DO, Githaka N, Sears KP, Knowles DP, Fry LM.Equine theileriosis, a tick-transmitted disease caused by the hemoprotozoan parasites Theileria equi and Theileria haneyi, affects equids throughout tropical and subtropical regions of the world. It is a significant regulatory concern in non-endemic countries, where testing for equine theileriosis is required prior to horse import to prevent parasite entry. Within endemic areas, infection causes significant morbidity and mortality, leading to economic losses. No vaccine for equine theileriosis is available, and current drug treatment protocols are inconsistent and associated with significant s...
Springer A, Ehrmann C, Lembcke M, Roscher K, Strube C.Equine piroplasmosis, caused by the protozoan pathogens or , is endemic in many (sub-)tropical regions worldwide, including Southern Europe. In Germany, it mainly plays a role as an imported parasitosis. Nevetherless, tick species with known vector potential for equine piroplasms occur in Germany. Thus, a long-term establishment of autochthonous cycles after introduction via infected equids or ticks cannot be excluded. In the present case, 2 horses developed clinical infection after returning from a trail riding trip to southern France. During treatment, a feeding tick was discovered on one ...
Song J, Song R, Wang P, Zhang Y, Yan Y, Zhou J, Chahan B, Liao M.The erythrocytic-stage surface protein equi merozoite antigen 1 (EMA-1) of Theileria equi is a major candidate for the development of a diagnostic antigen for equine piroplasmosis. In this study, BALB/c mice were immunized with purified recombinant EMA-1 to prepare monoclonal antibody (mAb) against T. equi EMA-1, and 1 mAb 5H2 was obtained that showed good reaction with infected red blood cells (RBC) in the indirect immunofluorescence assay (IFA). To develop a rapid serological detection method for T. equi infection in Xinjiang Uygur Autonomous Region, China, recombinant EMA-1 originating from...
Lei R, Wang X, Zhang D, Liu Y, Chen Q, Jiang N.Equine piroplasmosis (EP) is a severe disease of horses caused by the tick-borne protozoa Theileria equi (T. equi) and Babesia caballi (B. caballi). Infectious carriers are not always symptomatic, meaning there is a risk to non-enzootic areas. Regulatory tests for EP include sero-epidemiological methods for equine babesiosis, but these lack specificity due to cross-reactivity with other Babesia species. In this study, we present a real-time quantitative recombinase polymerase amplification (qRPA) method for fast simultaneous detection of both T. equi and B. caballi. In this method, primers and...
Tirosh-Levy S, Steinman A, Einhorn A, Apanaskevich DA, Mumcuoglu KY, Gottlieb Y.Theileria equi Mehlhorn and Schein, 1998 (Piroplasmida: Babesiidae) is an important tick-borne pathogen of horses that is highly endemic in many parts of the world, including Israel. The present study evaluated the potential roles of five hard tick species [Hyalomma excavatum Koch, 1844; Hyalomma marginatum Koch, 1844; Rhipicephalus turanicus Pomerantsev 1936; Rhipicephalus annulatus Say, 1821; Haemaphysalis parva (Neumann, 1897) (all: Ixodida: Ixodidae)], previously found to infest horses in Israel, in acting as vectors for piroplasmosis. For this, DNA was extracted from whole ticks and, when...
Mostafavi E, Esmaeilnejad B, Meysam Abtahi Foroushani S.This study was undertaken to assess the effects of T. equi infection on serum concentrations of some important cytokines including interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), and interleukin-1 beta (IL-1β), IL-1α, IL-4, IL-6, IL-8, IL-10, IL-12α, IL-12β, IL-18, as well as total, protein and lipid binding sialic acids (TSA, PBSA and LBSA). Furthermore, any probable relation among the parasitemia, cytokines and sialic acids (SAs) were calculated using Pearson correlation and simple linear regression. Almost 300 draft horses (Kurdish-breed) with age of 3-4 years old from north-...
Tirosh-Levy S, Gottlieb Y, Mimoun L, Mazuz ML, Steinman A.Although the main route of transmission of is through tick feeding, transplacental transmission is also possible and may lead to abortion, or to the birth of a sick or carrier foal. The aim of this study was to evaluate the role of as a cause of abortions in Israel and the risk of foals being infected at a young age. Eight aborting mares were serologically evaluated for exposure to via the immunofluorescence antibody test (IFAT) and their aborted fetuses were evaluated using PCR and qPCR. In addition, five mares and their foals (aged 4-6 months) from a highly endemic farm were tested for i...
Tirosh-Levy S, Gottlieb Y, Steinman A.Stress has been suggested as a risk factor for Theileria equi peracute disease and may lead to relapse in clinical signs in chronically infected horses. The aim of this study was to assess the effect of stress on T. equi parasitemia in sub-clinically infected horses in two settings: horses hospitalized at a veterinary teaching hospital and horses from an endurance farm. Blood samples were collected from the hospitalized horses (n = 32) upon admission (T0) and at discharge (T1) from the hospital, and results were compared between horses that underwent surgery (stress) and other hospitalized...
Elata A, Mossaad E, Satti R, Matar N, Ohari Y, Xuan X, Inoue N, Suganuma K.In Sudan, donkeys are important animals, providing transportation and income possibilities. However, the prevalence of parasites in donkeys in Sudan has not been thoroughly characterized. Accordingly, in this study, we aimed to detect selected hemoprotozoan parasites in donkeys in West Omdurman, Khartoum State, Sudan, wherein people depend mainly on donkeys for their daily life. In total, 198 blood samples collected from donkeys in a local market in West Omdurman, were screened using serological and molecular diagnostic techniques. Serologically, 52 (26.3%), 56 (28.3%), and 19 (9.6%) samples w...
Coultous RM, McDonald M, Raftery AG, Shiels BR, Sutton DGM, Weir W.Theileria equi, one of the primary pathogens causing equine piroplasmosis, has previously been sub-classified into a number of clades on the basis of 18S SSU rRNA gene sequence diversity. This partitioning of the parasite population has potential implications for host immunity, treatment and vaccine development. To detect and identify different clade genotypes among and within individual equine blood samples, a novel PCR-based technique was designed and optimized. Theileria equi has only recently been described in The Gambia, and the developed genotyping technique was used to analyse blood sam...
Bhoora RV, Collins NE, Schnittger L, Troskie C, Marumo R, Labuschagne K, Smith RM, Dalton DL, Mbizeni S.Recently reported substantial genetic diversity within Theileria equi 18S rRNA gene sequences has led to the identification of five genotypes A, B, C, D, and E, complicating molecular and serological diagnosis. In addition, T. haneyi has lately been reported as a species closely related to the T. equi 18S rRNA genotype C (Knowles et al., 2018). Theileria spp. of this group have a monophyletic origin and are therefore referred to as Equus group to distinguish them from the remaining Theileria lineages (Jalovecka et al., 2019). In this study, we report on the development of genotype-specific qua...
Kumar S, Sudan V, Shanker D, Devi A.Equine piroplasmosis, caused by Babesia (Theileria) equi, is well reported from many parts of India. However, literature regarding its prevalence from semi arid India is limited. Alongside, there is complete absence of information about genetic characterization of B.(T.) equi and the associated genotypes from India. In the present study, the prevalence of B.(T.) equi was studied from semi arid India using 18S ribosomal gene based PCR assay. An overall prevalence rate of 10.46% was recorded. PCR was more sensitive and specific in comparison with blood smears. The found isolates were sequenced. ...
Camino E, Pozo P, Dorrego A, Carvajal KA, Buendia A, Gonzalez S, de Juan L, Dominguez L, Cruz-Lopez F.Serological analysis of equine piroplasmosis (EP), caused by Theileria equi and Babesia caballi, is included in the export testing requirements for most of the countries worldwide, thus involving a high economic impact on equine industry of EP-endemic countries, such as Spain. A total of 3368 serum samples from healthy horses collected prior to export between 2015 and 2018 in Spain were tested for antibodies against T. equi and B. caballi by using a competitive inhibition enzyme-linked immunosorbent assay (cELISA). The overall seroprevalence results in Spain revealed that almost a quarter of t...
Souza EAR, Araujo AC, Pires LCSR, Freschi CR, Azevedo SS, Machado RZ, Horta MC.Equine piroplasmosis, an economically important disease in horses, has so far not been reported in Pernambuco state, Brazil. This study aimed to evaluate the seroprevalence of anti-Babesia caballi and anti-Theileria equi antibodies based on the detection of these agents in equine blood and in ticks on horses in the municipality of Petrolina, Pernambuco, northeastern Brazil. Blood samples were drawn from 393 horses and sera were examined by ELISA. The presence of tick infestations was evaluated, and 101 ticks were subjected to DNA amplification for the detection of Babesia spp. by polymerase ch...
Aziz KJ, Al-Barwary LTO.Equine piroplasmosis is a major tick-borne disease that can lead to serious health problems and economic losses in horse industry. The aim of the study is to determine the prevalence of and in different species of Equus namely (Horse, mule, donkey and pony) by Giemsa stained blood films and competitive ELISA. Methods: This study was conducted at various geographic areas of Erbil governorate. A total of 349 blood samples from equine (209 horses, 62 mule, 57 donkey and 21 ponies) were collected to estimate the prevalence rate of and by using Giemsa stained blood smear and competitive ELISA. ...
Camino E, Dorrego A, Carvajal KA, Buendia-Andres A, de Juan L, Dominguez L, Cruz-Lopez F.Equine piroplasmosis (EP) is a tick-borne protozoan disease caused by Theileria equi and/or Babesia caballi. Clinical signs (fever, pale mucosal membranes, jaundice), anemia and hyperbilirubinemia have been associated with the disease. EP is widespread, has a significant economic impact on the equine industry and remains endemic in Spain. This study was carried out with samples belonging to 140 horses residing in Spain and showing common clinical signs of EP. A blood smear microscopic examination and a comparison between the different results obtained by competitive Enzyme-Linked Immunosorbent...
Nadal C, Bonnet SI, Marsot M.When studying a vector-borne disease, an eco-epidemiological approach is vital for a comprehensive understanding of how the pathogen circulates amongst populations. Equine piroplasmosis (EP), a tick-borne disease caused by the protozoans Babesia caballi and Theileria equi, is endemic in the Mediterranean basin of Europe and causes both animal health and economic issues for the equine sector. With no vaccine available, defining the episystem of the disease can help to identify which components of the host-pathogen-vector-environment system to target to improve preventive measures. In this syste...
Lei R, Wang X, Zhang D, Liu Y, Chen Q, Jiang N.Equine piroplasmosis (EP) is a severe disease of horses caused by the tick-borne protozoa Theileria equi (T. equi) and Babesia caballi (B. caballi). Infectious carriers are not always symptomatic, meaning there is a risk to non-enzootic areas. Regulatory tests for EP include sero-epidemiological methods for equine babesiosis, but these lack specificity due to cross-reactivity with other Babesia species. In this study, we present a real-time quantitative recombinase polymerase amplification (qRPA) method for fast simultaneous detection of both T. equi and B. caballi. In this method, primers and...
Sloboda M, Jirků M, Lukešová D, Qablan M, Batsukh Z, Fiala I, Hořín P, Modrý D, Lukeš J.Equine piroplasmosis caused by Babesia caballi and Theileria equi is widespread in Asia. The presence of these haemozoans in Mongolia was previously confirmed in domestic as well as in reintroduced Przewalski horses in which they cause significant pathology. The data on occurrence of piroplasms from Bactrian camels in Asia is lacking. A total of 192 horses, 70 Bactrian camels, and additional 16 shepherd dogs from the Hentiy province were included in our study. No clinical signs typical for piroplasmid infection were observed during the field survey. Microscopic examination revealed the presenc...
Díaz-Sánchez AA, Pires MS, Estrada CY, Cañizares EV, Del Castillo Domínguez SL, Cabezas-Cruz A, Rivero EL, da Fonseca AH, Massard CL....Equine piroplasmosis is a disease of Equidae, including horses, donkeys, mules, and zebras, caused by either Theileria equi or Babesia caballi. This disease represents a serious problem for the horse industry and its control is critical for the international trade of horses. The objective of the present study was to detect B. caballi and T. equi infections in horses reared in western Cuba. Blood samples from 100 horses were tested for the presence of piroplasms by using Giemsa-stained blood smears and nested PCR (nPCR) assays targeting merozoite antigen genes of B. caballi (bc48) and T. equi (...
Hailat NQ, Lafi SQ, al-Darraji AM, al-Ani FK.Clinical, haematological and pathological studies were undertaken in Jordan in a stud of 103 racing horses clinically suffering from babesiosis and apparently healthy animals. Out of 47 horses which participated in strenuous exercise, three mares showed sudden onset of immobility and reluctance to move and two mares died. Clinical examination revealed that these five horses (group 1) had fever, anorexia, weakness and severe icterus and, in two mares, haemoglobinuria. Haematological examination revealed that all five horses were heavily parasitized with Babesia equi. This was also found in four...
Gallusová M, Qablan MA, D'Amico G, Oborník M, Petrželková KJ, Mihalca AD, Modrý D.Rural areas of Romania, particularly the localities covering Danube Delta, are still not sufficiently explored in terms of epidemiological aspects, despite the large density of domestic animals living in close contact with people and natural environment of the Danube Delta Biosphere Reserve. Between 2010 and 2012, a survey on equine piroplasmids species was performed in this area, using a total of 178 horses, 15 donkeys and 177 dogs from 18 localities inside and outside the Danube Delta. None of the sampled hosts showed any clinical symptoms typical for equine piroplasmoses. A 25.4% overall pr...
Holman PJ, Chieves L, Frerichs WM, Olson D, Wagner GG.Babesia equi was continuously cultured through 90 passages in an enriched chemically defined basal medium (HL-1) supplemented with 20% fetal bovine serum and serum replacement factors, including lipid-rich bovine serum albumin, bovine insulin, and human transferrin. Cryopreservation and subsequent recovery of B. equi were easily achieved. Inoculation of a splenectomized and an intact horse with cultured infected erythrocytes resulted in parasitemias and B. equi in vitro reisolation from both animals. In vitro forms of the parasite resembled in vivo forms. After establishment, parasitemias of 1...
Georges KC, Ezeokoli CD, Sparagano O, Pargass I, Campbell M, D'Abadie R, Yabsley MJ.Equine piroplasmosis due to Theileria equi and Babesia caballi is endemic in Trinidad. A case of equine piroplasmosis due to T. equi was diagnosed in a thoroughbred foal at 10h post-partum. A high parasitaemia (63%) of piroplasms was observed in a Wright-Giemsa(®) stained thin blood smear from the foal. In addition, the 18S rRNA gene for Babesia/Theileria was amplified from DNA extracted from the blood of the foal and the mare. Amplified products were subjected to a reverse line blot hybridization assay (RLB), which confirmed the presence of T. equi DNA in the foal. The mare was negative by R...
Ribeiro AJ, Cardoso L, Maia JM, Coutinho T, Cotovio M.Piroplasmid protozoa Theileria equi and Babesia caballi and zoonotic rickettsial bacterium Anaplasma phagocytophilum are important agents of equine vector-borne diseases (EVBD). This study aimed at investigating the prevalence of infections with or exposure to these pathogens in horses from the north of Portugal. Blood was randomly collected from 162 horses, living in 72 different stables, to prepare Giemsa-stained slide smears. Additionally, plasma samples were tested for antibodies to T. equi and B. caballi by two competitive enzyme-linked immunosorbent assays and to A. phagocytophilum by an...
Santodomingo A, Sierra-Orozco K, Cotes-Perdomo A, Castro LR.Horses are among the domestic animals that closely interact with humans and are highly parasitized by ticks, which are the primary vectors of zoonoses. As horses in Tayrona National Natural Park (PNNT) are used as a means of transporting goods, luggage and people, they are in constant contact with wild animals, workers and tourists from different countries. These factors increase the transmission risk of hemoparasites. The purpose of this study was to determine the presence of Rickettsia sp., Anaplasma sp., and Theileria sp., in horse ticks in this protected area using conventional PCR. We col...
Sevinc F, Maden M, Kumas C, Sevinc M, Ekici OD.Blood and serum samples were taken from 481 horses, from a stud farm or a racecourse, and tested by microscopic examination of blood smears and cELISA for Theileria equi (T. equi) and Babesia caballi (B. caballi) infections. At the time of sampling, animals were also examined for tick infestations and clinical disease, which were not observed in any of the sampled horses. During the microscopic examination of thin blood smears, parasites were detected in the three horses from the racecourse. Overall seroprevalence of infection was detected as 18.50% (89 of 481 horses) by cELISA, with T. equi b...
Sigg L, Gerber V, Gottstein B, Doherr MG, Frey CF.In Switzerland, the prevalence and incidence of equine piroplasma parasite (EPP) infections are unknown. In order to obtain a first insight into the prevalence, a representative sample of 689 sera of horses from Switzerland was serologically tested for the presence of antibodies directed against T. equi and B. caballi using the Indirect Fluorescence Antibody Test (IFAT). A total of 50 (7.3%) horses were seropositive for EPP: overall, the seroprevalence of T. equi was significantly higher than that of B. caballi (p=0.002). The seropositivities in indigenous horses (animals bred and raised in Sw...
Kerber CE, Labruna MB, Ferreira F, De Waal DT, Knowles DP, Gennari SM.Serum samples were collected from 582 horses from 40 stud farms in the State of São Paulo and tick (Acari: Ixodidae) infestations were evaluated on them. Serum samples were subjected to the complement fixation test (CFT) and a competitive inhibition ELISA (cELISA) for Babesia caballi and Theileria equi. Logistic regression analyses were performed to construct multivariate models that could explain the dependent variable (horses positive for B. caballi or T. equi) as a function of the independent variables (presence or abundance of each one of the tick species found on the farms). A higher ove...
Narankhajid M, Yeruult C, Gurbadam A, Battsetseg J, Aberle SW, Bayartogtokh B, Joachim A, Duscher GG.Ticks are cosmopolitan vectors of numerous diseases, and detection of various pathogens in ticks can help to assess their distribution. In the current study, 528 adult ticks were collected from grazing animals or the ground in ten different Mongolian provinces. Dermacentor nuttalli constituted 76.1% of them and was found in all ecozones except the eastern desert. Dermacentor marginatus (8.3%), Dermacentor silvarum (1.1%) and Ixodes persulcatus (3.0%) were found in the northern forest areas and Hyalomma asiaticum (11.4%) only in the southern (semi-)desert. Of these, 359 ticks were subjected to ...
Sumbria D, Das Singla L, Sharma A.A cross-sectional study was conducted in Submountain undulating, Undulating plain, Western and Western plain agro-climatic zones of Punjab province, India, to determine the prevalence, agreement between diagnostic tests and associated related risk factors of Theileria equi and Babesia caballi infection in equids (horses, donkey, mules). An overall prevalence of 14.14 and 0.0% of T. equi and B. caballi was recorded by multiplex polymerase chain reaction targeting 18S ribosomal RNA (rRNA) for both the parasites and 75 and 1.11% by competitive enzyme-linked immunosorbent assay in a representative...
Silva MG, Bastos RG, Stone Doggett J, Riscoe MK, Pou S, Winter R, Dodean RA, Nilsen A, Suarez CE.The most common apicomplexan parasites causing bovine babesiosis are Babesia bovis and B. bigemina, while B. caballi and Theileria equi are responsible for equine piroplasmosis. Treatment and control of these diseases are usually achieved using potentially toxic chemotherapeutics, such as imidocarb diproprionate, but drug-resistant parasites are emerging, and alternative effective and safer drugs are needed. The endochin-like quinolones (ELQ)-300 and ELQ-316 have been proven to be safe and efficacious against related apicomplexans, such as Plasmodium spp., with ELQ-316 also being effective aga...
Shkap V, Cohen I, Leibovitz B, Savitsky , Pipano E, Avni G, Shofer S, Giger U, Kappmeyer L, Knowles D.Sera from 361 horses were tested by indirect immunofluorescence antibody test (IFA) and by competitive inhibition ELISA (cELISA), to detect antibodies to Babesia equi. The concordance between the assays was 95.7%. Application of a cutoff based on a calculated percent inhibition of 20% inhibition was used. Approximately one-third of all the horses tested were found serologically positive to B. equi, with more horses testing positive from northern Israel. Among horses raised with access to pasture there was a significant difference in the percentage of seropositive reactors (76.6% in the north ...
Ramadan RM, Taha NM, Auda HM, Elsamman EM, El-Bahy MM, Salem MA.Equine piroplasmosis is not fully understood regarding pathogenicity, prophylaxis, host immune response expression, and specific vectors. Accurately identifying the parasite vector is crucial for developing an effective control plan for a particular infection. This study focused on morphologically identifying two Hyalomma species (H. anatolicum and H. marginatum) and one Rhipicephalus annulatus (R. annulatus) at the species level. The identification process was followed by phylogenetic analysis using the neighbor-joining method based on the cytochrome oxidase subunit 1 (COXI) gene as a specifi...
Liu Q, Meli ML, Zhang Y, Meili T, Stirn M, Riond B, Weibel B, Hofmann-Lehmann R.A reverse line blot (RLB) hybridization assay was adapted and applied for equine blood samples collected at the animal hospital of the University of Zurich to determine the presence of piroplasms in horses in Switzerland. A total of 100 equine blood samples were included in the study. The V4 hypervariable region of the 18S rRNA gene was amplified by polymerase chain reaction and analyzed using the RLB assay. Samples from seven horses hybridized to a Theileria/Babesia genus-specific and a Theileria genus-specific probe. Of these, two hybridized also to the Theileria equi-specific probe. The oth...
Butler CM, Nijhof AM, van der Kolk JH, de Haseth OB, Taoufik A, Jongejan F, Houwers DJ.Imidocarb treatment of horses infected with Babesia caballi is supposed to eliminate the infection, but data on the efficacy of this treatment is scarce. The study presented here concerns four Paso Fino horses, which were imported into the island of Curacao on the basis of a piroplasmosis negative complement fixation test (CFT). Upon re-testing with an indirect fluorescent antibody test immediately after arrival in Curacao, two horses appeared to have antibodies to B. caballi and all horses had antibodies to Theileria equi. Subsequent testing with polymerase chain reaction combined with a reve...
Knowles DP.Infection of horses with the hemoprotozoan Babesia equi has been reported in southern Florida, US Virgin Islands, part of Asia, Russia, India, the Middle East, Europe, Africa, Australia, South America, Central America, Mexico, Philippine Islands and some Caribbean islands. The restrictions placed on the international movement of infected horses has refocused attention on potential methods to control or eliminate infection. Don Knowles here discusses the primary chemotherapeutic compounds that have been used; the current knowledge concerning immune responses that potentially contribute to contr...
Zanet S, Bassano M, Trisciuoglio A, Taricco I, Ferroglio E.Equine Piroplasmosis (EP) caused by Theileria equi and Babesia caballi is a disease affecting the health and the international movement of horses. In order to assess prevalence of Piroplasmid infection in the Northwestern part of Italy and to evaluate the associated risk factors, whole blood was collected from 135 horses from 7 different stables across the study area. PCR and sequencing were used to assess prevalence of infection and to identify detected Piroplasms to species level. A total of 23 horses (P=17.04%; CI95%: 10.70-23.38%) was found to be infected with Piroplasms and T. equi was th...
Huang X, Xuan X, Xu L, Zhang S, Yokoyama N, Suzuki N, Igarashi I.An immunochromatographic test (BeICT) for the rapid detection of antibodies against Babesia equi was developed. It clearly differentiated B. equi-infected horses from B. caballi-infected and uninfected horses. The agreement with enzyme-linked immunosorbent assay results was 96.7% in the detection of field sera. The results suggest that BeICT is rapid, simple, reliable, and suitable for use to detect B. equi infection in the field.
Wise LN, Kappmeyer LS, Silva MG, White SN, Grause JF, Knowles DP.Certain countries including the United States remain non-endemic for particular infectious diseases such as equine piroplasmosis through import restrictions and surveillance. Endemic regions often employ premunition as the primary method to control disease, however in non-endemic countries, chemosterilization combined with methods to confirm parasite elimination are required to maintain disease-free status. The ability of imidocarb diproprionate (ID) to clear persistent Theileria equi infection from infected horses has been shown through the inability of treated horses to transmit via blood tr...
Boldbaatar D, Xuan X, Battsetseg B, Igarashi I, Battur B, Batsukh Z, Bayambaa B, Fujisaki K.The purpose of this study was to demonstrate the occurrence of equine piroplasmosis in Mongolia, a country in which the disease occurs epidemically in different climatic conditions. Antibodies to Babesia equi and B. caballi were determined in serum samples of 254 pastured horses in different locations of Mongolia using an enzyme-linked immunosorbent assay with recombinant antigens. One hundred and eighty-five (72.8%) and 102 (40.1%) of all serum samples were positive for B. equi and B. caballi infections, respectively. In addition, 78 (30.7%) samples were positive for both B. equi and B. cabal...
Farkas R, Tánczos B, Gyurkovszky M, Földvári G, Solymosi N, Edelhofer R, Hornok S.The prevalence of Theileria equi infection was studied in 324 healthy horses from 27 farms in Hungary with cELISA and IFAT and the blood samples of 101 horses selected randomly were also examined by PCR. The results indicate that there are many stud farms where one or more horses are infected with T. equi. Among 27 farms 17 (67.9%) were found to have seropositive horses. The seroprevalence of theileriosis among the tested stud farms ranged between 0 and 100%. No marked differences were found in seropositivity between geographical areas. The overall prevalence of positive samples was 32.0% with...
Camino E, Dorrego A, Carvajal KA, Buendia-Andres A, de Juan L, Dominguez L, Cruz-Lopez F.Equine piroplasmosis (EP) is a tick-borne protozoan disease caused by Theileria equi and/or Babesia caballi. Clinical signs (fever, pale mucosal membranes, jaundice), anemia and hyperbilirubinemia have been associated with the disease. EP is widespread, has a significant economic impact on the equine industry and remains endemic in Spain. This study was carried out with samples belonging to 140 horses residing in Spain and showing common clinical signs of EP. A blood smear microscopic examination and a comparison between the different results obtained by competitive Enzyme-Linked Immunosorbent...
Manna G, Cersini A, Nardini R, Bartolomé Del Pino LE, Antognetti V, Zini M, Conti R, Lorenzetti R, Veneziano V, Autorino GL, Scicluna MT.Babesia caballi and Theileria equi are tick-borne pathogens causing equine piroplasmosis infecting the Equidae family in which they cause significant sanitary and economic losses. Furthermore, equine piroplasmosis is included in the World Animal Health Organization (OIE) notifiable diseases list with possible movement restrictions for positive horses. Thirty-nine EDTA and whole-blood samples collected during 2013 and 2014 from symptomatic and asymptomatic horses of Central-Southern Italy were included in the present study either because of their strongly positive results in Real Time (RT) PCRs...
Zweygarth E, Just MC, de Waal DT.The protozoan parasite Babesia equi, a causative agent of equine piroplasmosis, was continuously cultivated in horse erythrocytes. The parasites were isolated from a carrier horse at a time when no parasite was detected in a thin blood smear. The culture medium consisted of modified medium 199 supplemented with 40% non-heat-inactivated horse serum in a humidified atmosphere containing 5% CO2, 2% O2, and 93% N2 at 37 degrees C. Parasites were detected after 2 days in culture. When the percentage of parasitized erythrocytes (PPE) reached 1%, the cultures were transferred into a humidified atmosp...
Rüegg SR, Heinzmann D, Barbour AD, Torgerson PR.For the evaluation of the epidemiology of Theileria equi and Babesia caballi in a herd of 510 horses in SW Mongolia, several mathematical models of the transmission dynamics were constructed. Because the field data contain information on the presence of the parasite (determined by PCR) and the presence of antibodies (determined by IFAT), the models cater for maternal protection with antibodies, susceptible animals, infected animals and animals which have eliminated the parasite and also allow for age-dependent infection in susceptible animals. Maximum likelihood estimation procedures were used...
