Serology in horse research involves the study and analysis of blood serum to detect the presence of antibodies or antigens associated with infectious diseases and other health conditions. It is a diagnostic tool used to identify immune responses to pathogens, vaccination status, and exposure to specific diseases. Serological tests in equine research can include enzyme-linked immunosorbent assays (ELISA), complement fixation tests, and virus neutralization tests. These tests help in understanding the epidemiology of diseases, monitoring herd health, and informing vaccination strategies. This page compiles peer-reviewed research studies and scholarly articles that explore the methodologies, applications, and implications of serological testing in equine medicine.
Shi N, Qiu X, Cao X, Mai Z, Zhu X, Li N, Zhang H, Zhang J, Li Z, Shaya N, Lu H, Jin N.The Getah virus (GETV), a mosquito-borne RNA virus, is widely distributed in Oceania and Asia. GETV is not the only pathogenic to horses, pigs, cattle, foxes and boars, but it can also cause fever in humans. Since its first reported case in Chinese mainland in 2017, the number of GETV-affected provinces has increased to seventeen till now. Therefore, we performed an epidemiologic investigation of GETV in the Xinjiang region, located in northwestern China, during the period of 2017-2020. ELISA was used to analyze 3299 serum samples collected from thoroughbred horse, local horse, sheep, goat, ca...
Verney M, Gautron M, Lemans C, Rincé A, Hans A, Hébert L.Trypanozoon infections in equids are caused by three parasite species in the Trypanozoon subgenus: Trypanosoma equiperdum, T. brucei and T. evansi. They are respectively responsible for infectious diseases dourine, nagana and surra. Due to the threat that Trypanozoon infection represents for international horse trading, accurate diagnostic tests are crucial. Current tests suffer from poor sensitivity and specificity, due in the first case to the transient presence of parasites in the blood and in the second, to antigenic cross-reactivity among Trypanozoon subspecies. This study was designed to...
Lee SK, Park D, Lee I.Equine parvovirus-hepatitis (EqPV-H) causes equine hepatitis. The prevalence of EqPV-H in healthy horses has been reported in the United States, China, Germany, and Austria. The present study determined the prevalence of EqPV-H in the sera of clinically healthy horses in South Korea to identify the potential factors for infection and examine the genetic diversity of EqPV-H DNA sequences through comparison with foreign strains. Serum samples collected from 321 horses were tested for EqPV-H using non-structural protein 1 (NS1)-specific polymerase chain reaction. The associations of EqPV-H infect...
Pradella GD, Duarte CA, Escobar TA, Zuravski L, Góss GC, Skupien JA, Lübeck I.The Leishmaniases are on the top of the global list of tropical neglected diseases. The number of infected dogs in South America is estimated in millions and correlated to disease cases in humans, especially in Brazil. Equines may get infected too and can play a role in the epidemiological chain. Thus, the aim of the present study was to evaluate risk and protective factors of leishmaniasis in rural areas of the western border region of Rio Grande do Sul state, Brazil by Leishmania spp. protozoa molecular detection and serological evaluation (ELISA) in equine and canine blood samples. This wor...
Campos JBV, Martins FS, de Oliveira CE, Taveira AA, Oliveira JR, Gonçalves LR, Cordeiro MD, Calchi AC, de Campos Binder L, Serpa MCA, Barbieri ARM....The emergence of tick-borne diseases has been reported as a serious problem in public health worldwide and many aspects of its epidemiology and effects on the health of its hosts are unclear. We aimed to perform an epidemiological study of tick-borne zoonotic Rickettsia, Borrelia, and Anaplasmataceae in horses from Midwestern Brazil. We also evaluated whether Borrelia spp. and Anaplasmataceae may be associated with hematological disorders in the sampled animals. Blood and serum samples as well as ticks were collected from 262 horses. Serum samples were used to perform serological tests, and he...
McNabb L, Andiani A, Bulavaite A, Zvirbliene A, Sasnauskas K, Lunt R.Zoonotic transmission of Hendra virus (HeV) from primary hosts (pteropid bats) to horses, and, occasionally, onward adventitious spread to humans, is associated with high mortality rates in both affected secondary species. The introduction of an effective recombinant G protein vaccine for use in horses has been a major advance for the suppression of disease risk. However, equine HeV vaccination induces neutralising antibody that is indistinguishable from a post infection immune response when using most first line serology assays (eg. VNT and some ELISAs). We have constructed and evaluated an I...
de Heus P, Kolodziejek J, Hubálek Z, Dimmel K, Racher V, Nowotny N, Cavalleri JV.The emergence of West Nile virus (WNV) and Usutu virus (USUV) in addition to the autochthonous tick-borne encephalitis virus (TBEV) in Europe causes rising concern for public and animal health. The first equine case of West Nile neuroinvasive disease in Austria was diagnosed in 2016. As a consequence, a cross-sectional seroprevalence study was conducted in 2017, including 348 equids from eastern Austria. Serum samples reactive by ELISA for either flavivirus immunoglobulin G or M were further analyzed with the plaque reduction neutralization test (PRNT-80) to identify the specific etiologic age...
Alnaeem A, Shawaf T, Ali AM, Hemida MG.In the current study, we are investigating the viral causes of some respiratory clinical signs in some animals belongs to the family Equidae in eastern Saudi Arabia (ESA) during winter- 2019. We observed the progression of severe respiratory clinical signs among some horses, donkeys, and ponies in the ESA. Animals showed rapid respiration, fever, nasal discharges (started as serous then changed into mucopurulent with the progression of the infection per some animals). We conducted a longitudinal study to monitor the progression of this outbreak. We conducted molecular surveillance for the infl...
Bażanów B, Pawęska JT, Pogorzelska A, Florek M, Frącka A, Gębarowski T, Chwirot W, Stygar D.Huculs () are an old breed of primitive mountain horses, originating from the Carpathian Mountains. To the best of our knowledge, data concerning the epidemiology of viral infections observed within this breed are sparse. The objective of this study was to estimate the serological status of a semi-isolated, unvaccinated Hucul herd, with respect to both common equine viral infections and horse-infecting arboviruses, the presence of which was previously reported in Poland. Twenty horses of the Hucul breed, living in a remote area in Poland, were studied in 2018 from March to May. Using nasal sec...
Reinecke B, Klöhn M, Brüggemann Y, Kinast V, Todt D, Stang A, Badenhorst M, Koeppel K, Guthrie A, Groner U, Puff C, de le Roi M, Baumgärtner W....Since its first discovery by Arnold Theiler in 1918, serum hepatitis also known as Theiler's disease has been reported worldwide, causing idiopathic acute hepatitis and liver failure in horses. Recent studies have suggested a novel parvovirus, named equine parvovirus hepatitis (EqPV-H), to be associated with Theiler's disease. Despite the severity and potential fatality of EqPV-H infection, little is known about the possibility of developing chronic infections and putative cross-species infection of equine sister species. In the present longitudinal study, we employed qPCR analysis, serology, ...
Jonsdottir S, Torsteinsdottir S, Svansson V, Gudbrandsson J, Stefansdottir SB, Mar Bjornsson J, Runarsdottir A, Marti E.Insect bite hypersensitivity (IBH) is an allergic dermatitis of horses, an IgE-mediated reaction to Culicoides midges. Causative Culicoides spp. are not indigenous in Iceland resulting in high prevalence of IBH in horses born in Iceland and exported as compared to Icelandic horses born in a Culicoides rich environment. The aims were (i) to compare IgE levels in sera of IBH-affected horses born in Iceland (n = 47) with horses of the Icelandic breed (n = 23) and of other breeds (n = 27) born in Culicoides infested area; (ii) to investigate if barley could be a useful production system of allerge...
Mayo CE, Weyer CT, Carpenter MJ, Reed KJ, Rodgers CP, Lovett KM, Guthrie AJ, Mullens BA, Barker CM, Reisen WK, MacLachlan NJ.The availability of rapid, highly sensitive and specific molecular and serologic diagnostic assays, such as competitive enzyme-linked immunosorbent assay (cELISA), has expedited the diagnosis of emerging transboundary animal diseases, including bluetongue (BT) and African horse sickness (AHS), and facilitated more thorough characterisation of their epidemiology. The development of assays based on real-time, reverse-transcription polymerase chain reaction (RT-PCR) to detect and identify the numerous serotypes of BT virus (BTV) and AHS virus (AHSV) has aided in-depth studies of the epidemiology ...
Wasiński B, Paschalis-Trela K, Trela J, Czopowicz M, Kita J, Żychska M, Cywińska A, Markowska-Daniel I, Carter C, Witkowski L.Leptospirosis is one of the most common zoonotic infections worldwide, including in most livestock, some companion animals, horses, wildlife, and humans. Epidemiological estimation of its prevalence in all species is difficult due to the variety of clinical presentations and challenges regarding laboratory diagnosis. The purpose of this study was to measure the seroprevalence of leptospiral infection in Arabian horses kept in the largest breeding farms in Poland, representing over 15% of the Polish Arabian horse population. Leptospira antibodies were detected by MAT (cut-off 1:100) in 33.2% of...
Neely M, Arroyo L, Jardine C, Clow K, Moore A, Hazlett M, Weese JS.The blacklegged tick (), which transmits , the causative agent of Lyme disease, has undergone rapid range expansion in Ontario. In horses, Lyme disease remains an enigmatic disease, with limited understanding of the pathogenesis and many issues pertaining to selection and interpretation of laboratory tests. We evaluated seropositivity in naturally exposed horses over a 12-mo period and compared paired samples with 2 common serologic tests. Serum samples were collected in 2017, ~1 y after initial testing, from a cohort of 22 horses that were seropositive in a 2016 seroprevalence study. Sampl...
Reck C, Menin Á, Batista F, Meira Santos PO, Miletti LC.Surra is an infectious disease caused by , which affects a large number of domestic and wild animal species. Infection control is based on rapid diagnosis followed by treatment of sick animals. This study aimed to evaluate a buffered antigen and rapid serum agglutination test (BA/Te) for the detection of anti- antibodies in serum samples of horses. For this purpose, 445 serum samples from horses were evaluated and the results compared with the diagnosis by CATT/. Our data show a sensitivity of 92%, specificity of 91% and a degree of agreement kappa () of 0.82 (95% CI: 0.771-0.877, < 0...
Idoko IS, Edeh RE, Adamu AM, Machunga-Mambula S, Okubanjo OO, Balogun EO, Adamu S, Johnson W, Kappmeyer L, Mousel M, Ueti MW.Equine piroplasmosis, an economically important disease of equids caused by the hemoprotozoan parasites , , and , has a worldwide distribution. These parasites are transmitted by ixodid ticks. To improve the detection of horses in Nigeria exposed to piroplasm parasites, 72 horses with variable clinical signs of piroplasmosis were sampled from Northwest and Northcentral Nigeria and tested by nPCR and cELISA. Blood and serum samples were collected from each horse via jugular venesection. Individually, nPCR or cELISA failed to identify all horses exposed to piroplasms. A combination of species-sp...
Tirosh-Levy S, Mazuz ML, Savitsky I, Pinkas D, Gottlieb Y, Steinman A.Babesia caballi is a tick-borne hemoparasite of equines and one of the causative agents of equine piroplasmosis, which poses a great concern for the equine industry regarding animal welfare and international horse movement. The parasite is endemic in Israel; however, its seroprevalence in the area was never evaluated due to antigenic heterogenicity in the gene used in the commercially available kit. Blood samples were collected from 257 horses at 19 farms throughout the country and screened for the presence of anti-B. caballi antibodies via an indirect immunofluorescent antibody test (IFAT) an...
Jaferi M, Mozaffari A, Jajarmi M, Imani M, Khalili M.There are few reports about Q fever in horse populations worldwide. This study aimed to detect the C. burnetii infection by serologic and molecular confirmation using commercial ELISA kit and real-time PCR in the East of Iran a region highly endemic. A total of 177 blood samples and 115 vaginal swabs were randomly collected from horses in East of Iran. The sera samples were analyzed for anti C.burnetii Ig G antibodies by a commercial ELISA kit and nucleic acid extraxted from vaginal samples were used to determine the C. burnetii DNA by real-time PCR assay. Antibodies were detected in 5.64 % (1...
Weber MN, Mosena ACS, Baumbach LF, da Silva MS, Canova R, Dos Santos DRL, Budaszewski RDF, de Oliveira LV, Soane MM, Saraiva NB, Bellucco FT....Flaviviruses as West Nile virus (WNV), Saint Louis encephalitis virus (SLEV), Ilhéus virus (ILHV), and Rocio virus (ROCV) are previously reported in different Brazilian regions, but studies in Southern Brazil are still scarce. To improve the information regarding flaviviruses in Southern Brazil, horse serum samples were analyzed using RT-qPCR and a commercial ELISA-Ab against WNV followed by PRNT. All 1000 samples analyzed by real-time RT-PCR resulted negative. The 465 subsampled samples were analyzed by a commercial ELISA-Ab against WNV, and the 18.5% (86/465) positive samples were further a...
Romo-Sáenz CI, Tamez-Guerra P, Olivas-Holguin A, Ramos-Zayas Y, Obregón-Macías N, González-Ochoa G, Zavala-Díaz de la Serna FJ....Equine infectious anemia (EIA) is a highly infectious disease in members of the family, caused by equine infectious anemia virus (EIAV). The disease severity ranges from subclinical to acute or chronic, and causes significant economic losses in the equine industry worldwide. Serologic tests for detection of EIAV infection have some concerns given the prolonged seroconversion time. Therefore, molecular methods are needed to improve surveillance programs for this disease. We attempted detection of EIAV in 6 clinical and 42 non-clinical horses in Nuevo Leon State, Mexico, using the agar gel immu...
Nunes JDSDSS, Casseb LMN, Guimarães RJPS, Reis WDM, de Barros BCV, Ferreira MS, Chiang JO, Pinheiro HHC, Vasconcelos PFDC, Cruz ACR.Serum samples from 89 equids were analyzed (75 horses, 9 donkeys, and 5 mules) from the municipality of Viseu, Pará state, Brazil. Samples were collected in November 2014 and August 2015. The antibody prevalence against the following alphaviruses was estimated: Eastern equine encephalitis virus, Western equine encephalitis virus, Mucambo virus, and Mayaro virus. Seroprevalence was determined by the hemagglutination inhibition (HI) technique. Sera that exhibited HI antibodies with heterotypic reactions for the analyzed viruses were subjected to the 90% plaque reduction neutralization test (PRN...
Björnström A, Blomström AL, Singh MC, Hesson JC.A number of viruses transmitted by mosquitoes are well known to cause disease in both humans and horses, ranging from mild fevers to mortal neurological disease. A recently discovered connection between the alphavirus Sindbis virus (SINV) and neurological disease in horses in South Africa initiated this serological study in northern Europe, where the same genotype of SINV (SINV-I) is also highly endemic. We tested 171 serum samples, originally obtained from horses for other reasons from April to October 2019, for presence of SINV neutralising antibodies using a plaque reduction neutralisation ...
Boyle AG, Mitchell C, Stefanovski D, Waller AS.The dual antigen iELISA uses two Streptococcus equi subsp equi surface protein antigens composed of N-terminal portions of SEQ2190 (Antigen A) and SeM (Antigen C). It is currently used to identify animals exposed to S. equi which have developed an immune response to the target antigens. Objective: To determine the usefulness of the dual antigen iELISA in a population of horses vaccinated with Pinnacle IN. We hypothesised that horses vaccinated for strangles with a live attenuated, non-encapsulated SeM-2 strain of S. equi, would seroconvert when tested 5 weeks later by the dual antigen iELIS...
Muraro LS, Souza AO, Leite TNS, Cândido SL, Melo ALT, Toma HS, Carvalho MB, Dutra V, Nakazato L, Cabezas-Cruz A, Aguiar DM.The genus includes tick-borne bacterial pathogens affecting humans, domestic and wild mammals. has been identified in different animal species and geographical locations, suggesting that this is a widely distributed and generalist . In the present study, we evaluated infection in 148 Equidae presented to the Medical Clinic Department of a Veterinary Hospital from a midwestern region of Brazil. Blood samples and ticks collected from the animals were tested by Polymerase Chain Reaction (PCR) for the presence of spp. A multigenic approach including Anaplasmataceae-specific (i.e., 16S rRNA, , ...
Elschner MC, Melzer F, Singha H, Muhammad S, Gardner I, Neubauer H.Glanders, caused by Burkholderia (B.) mallei is a notifiable zoonotic disease in equidae. For international trade and movement of equids, certificates of negative serological test results for antibodies against B. mallei are required. To date, the complement fixation test (CFT) is the mandatory test to issue these health certificates. The CFT is difficult to standardize and, due to its poor specificity, often leads to false-positive reactions resulting in trade restrictions with considerable financial consequences. In the present study, the new ID Screen Glanders Double Antigen Multispecies EL...
Bogdan AM, Ionita M, Mitrea IL.The purpose of this study was to investigate the seroprevalence of selected tick-borne-pathogens (TBPs) among Romanian horses. For this, a total of 223 animals originating from north, central, and southeast Romania, including horses from stud farms ( = 118) and working horses ( = 105), were tested using a commercial rapid ELISA-based test. Overall, 10.3% (95% confidence interval (CI): 6.7-15.1%) of the tested horses were seropositive for antibodies (Ab) against Additionally, 18.8% (95% CI: 13.9-24.6%) and 0.5% (95% CI: 0.01-2.5%) of horses were seropositive for Ab against sensu lato and spp...
Reemers S, van Bommel S, Cao Q, Sutton D, van de Zande S.Equine influenza virus (EIV) is a major cause of respiratory disease in horses. Vaccination is an effective tool for infection control. Although various EIV vaccines are widely available, major outbreaks occurred in Europe in 2018 involving a new EIV H3N8 FC1 strain. In France, it was reported that both unvaccinated and vaccinated horses were affected despite >80% vaccination coverage and most horses being vaccinated with a vaccine expressing FC1 antigen. This study assessed whether vaccine type, next to antigenic difference between vaccine and field strain, plays a role. Horses were vaccin...
Di Francesco CE, Smoglica C, De Amicis I, Cafini F, Carluccio A, Contri A.Eight Martina Franca pregnant jennies were selected in order to evaluate the transfer of colostral antibodies against equine herpesvirus type 1 in their relative foals after immunization with a commercial inactivated vaccine, compared with an unvaccinated group. Samples of serum and colostrums/milk were collected from jennies and foals under study starting from 10 min before and up to 21 days after the foaling. Specific anti-EHV-1 antibody titers were evaluated by means of a serum neutralization test, and the results obtained from both groups were analyzed. The serological titers in the vaccin...
Leszkowicz Mazuz M, Mimoun L, Schvartz G, Tirosh-Levy S, Savitzki I, Edery N, Blum SE, Baneth G, Pusterla N, Steinman A.In horses, and have been associated with fetal loss, and neurological disease, respectively. This study investigated the role of spp. infection in equine abortion in Israel. The presence of anti- spp. antibodies was evaluated in 31 aborting mares by indirect fluorescent antibody test (IFAT) and the presence of parasite DNA in their aborted fetuses was evaluated by polymerase chain reaction (PCR), using two target loci (ITS1 and Nc5). The seroprevalence found in aborting mares was 70.9% and the prevalence by DNA detection in the aborted fetuses was 41.9%. Transplacental transmission from pos...
Faber NA, Crawford M, LeFebvre RB, Buyukmihci NC, Madigan JE, Willits NH.Leptospiral organisms have long been presumed to be associated with the presence of equine recurrent uveitis. This project was undertaken to determine the presence of Leptospira spp. in the aqueous humor of horses with uveitis to determine if there was an association with inflammation. Thirty horses were determined to have recurrent uveitis based on clinical evaluation or history. Sixteen horses were judged clinically and historically to be free of uveitis and were used as controls. Aqueous humor samples were cultured and evaluated by PCR for the presence of Leptospira DNA. Serum was collected...
Beards GM, Brown DW, Green J, Flewett TH.Pleomorphic virus-like particles have been observed by electron microscopy in the faeces of children and adults with diarrhoea. Some of these particles were approximately 100 nm in diameter and had a "fringe" of closely applied peplomers approximately 10 nm long; they closely resembled Berne virus of horses and Breda virus of calves, the two representatives of a newly proposed family called the Toroviridae. In one sample a toroidal nucleoprotein-like structure was observed within the particles. For two samples a buoyant density of 1.14 g/ml was determined by centrifugation through a sucrose de...
Moretti A, Mangili V, Salvatori R, Maresca C, Scoccia E, Torina A, Moretta I, Gabrielli S, Tampieri MP, Pietrobelli M.Babesia caballi and Theileria equi are the causative agents of equine piroplasmosis. In this preliminary epidemiological study, 412 horses reared in central and northern Italy were sampled and three diagnostic methods compared, namely, the microscopy, the indirect fluorescent antibody test (IFAT) and a PCR. Possible risk factors (such as area, season, breed, activity, sex, age, and grazing) associated with serological positivity were evaluated. A seroprevalence of 68.4% was found: 12.4% of the animals had anti-T. equi antibodies, 17.9% anti-B. caballi antibodies and 38.1% had antibodies agains...
Adney DR, Brown VR, Porter SM, Bielefeldt-Ohmann H, Hartwig AE, Bowen RA.The Middle East respiratory syndrome coronavirus (MERS-CoV) was first recognized in 2012 and can cause severe disease in infected humans. Dromedary camels are the reservoir for the virus, although, other than nasal discharge, these animals do not display any overt clinical disease. Data from in vitro experiments suggest that other livestock such as sheep, goats, and horses might also contribute to viral transmission, although field data has not identified any seropositive animals. In order to understand if these animals could be infected, we challenged young goats and horses and adult sheep wi...
Zoonoses and public healthJuly 30, 2009
Volume 57, Issue 7-8 476-486 doi: 10.1111/j.1863-2378.2009.01245.x
Monaco F, Lelli R, Teodori L, Pinoni C, Di Gennaro A, Polci A, Calistri P, Savini G.In August 2008, West Nile disease re-emerged in Italy. The infection is affecting the North Eastern regions and, as of November 2008, has caused 33 clinical cases and five fatalities in horses. Until now, no deaths have been reported in birds. Mosquitoes, blood, serum and tissue samples, from horses and birds, within and around the outbreak area, have been collected and tested by various methods both serologically and virologically. West Nile virus strains have been isolated from blood samples of one horse and one donkey and from pools of brain, kidneys, heart and spleen of a pigeon and three ...
MacLachlan NJ, Balasuriya UB, Hedges JF, Schweidler TM, McCollum WH, Timoney PJ, Hullinger PJ, Patton JF.Equine arteritis virus (EAV) is the causative agent of equine viral arteritis, an apparently emerging disease of equids. In this study, the antibody response of horses to the structural proteins of EAV was evaluated using gradient-purified EAV virions and baculovirus-expressed recombinant EAV structural proteins (G(L), G(S), M, N) as antigens in a Western immunoblotting assay. Thirty-three sera from horses that previously had been naturally or experimentally infected with EAV were evaluated, including samples from mares, geldings, and both persistently and nonpersistently infected stallions. S...
Issel CJ, Adams WV, Meek L, Ochoa R.Twenty seven adult horses positive to the agar gel immunodiffusion (AGID) test for equine infectious anemia (EIA), but with no history of clinical EIA, were used in transfusion studies to determine whether infectious EIA virus was present in 1 to 5 ml of their blood. Of 27 recipients, 21 (78%) became AGID test-positive at an average of 24 days after inoculation. Two horses that were initially negative when screened were retested and found to carry infectious virus in 5-300 ml of whole blood; the other 4 horses were not retested. Horse flies (Tabanus fuscicostatus Hine) were unable to transmit ...
Beck C, Lowenski S, Durand B, Bahuon C, Zientara S, Lecollinet S.West Nile Fever is a zoonotic disease caused by a mosquito-borne flavivirus, WNV. By its clinical sensitivity to the disease, the horse is a useful sentinel of infection. Because of the virus' low-level, short-term viraemia in horses, the primary tools used to diagnose WNV are serological tests. Inter-laboratory proficiency tests (ILPTs) were held in 2010 and 2013 to evaluate WNV serological diagnostic tools suited for the European network of National Reference Laboratories (NRLs) for equine diseases. These ILPTs were designed to evaluate the laboratories' and methods' performances in detectin...
Mott J, Rikihisa Y, Zhang Y, Reed SM, Yu CY.Potomac horse fever is an acute systemic equine disease caused by Ehrlichia risticii. Currently, serologic methods are widely used to diagnose this disease. However, serologic methods cannot determine whether the horse is presently infected or has been exposed to ehrlichial antigens in the past. The purpose of the present study was to compare the sensitivities of the nested PCR and cell culture with that of the indirect fluorescent-antibody (IFA) test for the diagnosis of Potomac horse fever. Blood and fecal specimens serially collected from a pony experimentally infected with E. risticii Mary...
Thomson GR, Mumford JA, Campbell J, Griffiths L, Clapham P.An investigation was made of 3 serological tests (virus neutralization, complement fixation and indirect immunofluorescence), which are applicable to epidemiological studies of infections by Equid herpesvirus 1 (EHV-1). Sera from gnotobiotic foals inoculated intranasally with various strains of EHV-1 were unable in some cases to neutralize heterologous strains and these results were not consistent with the existence of clearly-defined subtypes of EHV-1, as previously proposed. The cross-reactions in complement-fixation tests paralleled those with neutralization but immunofluorescence tests wer...
Aleman M, Spier SJ, Wilson WD, Doherr M.To describe clinical manifestations of Corynebacterium pseudotuberculosis infection in horses and to evaluate diagnostic methods for identification of this disease. Methods: Retrospective case series. Methods: 538 horses with a diagnosis of C pseudotuberculosis infection. Results: Median age of horses with external abscesses was similar to that in horses with internal abscesses. Breed and sex did not appear to be associated with infection. Cases were detected during all 12 months; however, the disease was most common in the fall and early winter, with the highest incidence in September, Octobe...
Artursson K, Gunnarsson A, Wikström UB, Engvall EO.For diagnosis of equine granulocytic ehrlichiosis (EGE) serological testing of antibodies to Ehrlichia equi is frequently used. An elevated antibody level is often misinterpreted as confirmative of active infection and results in treatment with antibiotics. If only seropositivity is considered as the diagnostic criterium, many horses showing convalescence titres will be treated. This study was undertaken to obtain information about the kinetics of antibodies during the course of infection and, for this purpose, 45 horses with clinical signs of EGE and confirmed ehrlichiaemia were monitored ser...
Gardner IA, Wong SJ, Ferraro GL, Balasuriya UB, Hullinger PJ, Wilson WD, Shi PY, MacLachlan NJ.A prospective cohort study was used to estimate the incidence of West Nile virus (WNV) infection in a group of unvaccinated horses (n = 37) in California and compare the effects of natural WNV infection in these unvaccinated horses to a group of co-mingled vaccinated horses (n = 155). Horses initially were vaccinated with either inactivated whole virus (n = 87) or canarypox recombinant (n = 68) WNV vaccines during 2003 or 2004, prior to emergence of WNV in the region. Unvaccinated horses were serologically tested for antibodies to WNV by microsphere immunoassay incorporating recombinant WNV E ...
Parker JL, White KK.A complete search of the literature concerning Lyme borreliosis as it relates to horses and cattle was done. The epidemiology, pathogenesis, immunological response to the disease, diagnosis and treatment are discussed. A review of clinical cases in horses and cattle is presented. Clinical signs of Lyme borreliosis in horses include: chronic weight loss, sporadic lameness, laminitis, low grade fever, swollen joints, muscle tenderness, and anterior uveitis. In addition to those clinical signs, neurological signs such as depression, behavioral changes, dysphagia, head tilt and encephalitis can be...
Abdelgawad A, Hermes R, Damiani A, Lamglait B, Czirják GÁ, East M, Aschenborn O, Wenker C, Kasem S, Osterrieder N, Greenwood AD.Equine herpesvirus type 1 (EHV-1) causes respiratory disorders and abortion in equids while EHV-1 regularly causes equine herpesvirus myeloencephalopathy (EHM), a stroke-like syndrome following endothelial cell infection in horses. Both EHV-1 and EHV-9 infections of non-definitive hosts often result in neuronal infection and high case fatality rates. Hence, EHV-1 and EHV-9 are somewhat unusual herpesviruses and lack strict host specificity, and the true extent of their host ranges have remained unclear. In order to determine the seroprevalence of EHV-1 and EHV-9, a sensitive and specific pepti...
Kumar S, Kumar R, Sugimoto C.The donkey population has remained unchanged in the last two decades despite a decrease in the overall population of equids, emphasizing the usefulness of the donkey as a draught and pack animal. Piroplasmosis in donkeys, caused by Theileria equi and Babesia caballi, has been recognized as a serious problem of major economic importance as the affected animals manifest decreased working capacity, loss of appetite, etc. In tropical countries, T. equi infections are more wide-spread and pathogenic than those caused by B. caballi. Donkeys usually remain asymptomatic carriers with positive antibody...
van Maanen C, Sloet van Oldruitenborgh-Oosterbaan MM, Damen EA, Derksen AG.An outbreak of neurological disease caused by EHV-1 infection is described with emphasis on diagnosis and prognosis for recumbent horses. In April 1995, an outbreak of the neurological form of Equine herpesvirus type 1 (EHV-1) occurred in a well-managed riding school with 41 horses: 34 horses showed a temperature spike and 20 some degree of neurological signs, of which 10 were nursed intensively in the indoor arena of the riding school for 3 to 20 days, 8 having to be maintained in slings for 2-18 days, while 9 needed bladder catheterisation b.i.d. for 2-16 days. Within the first 3 days, one h...
Yamanaka T, Nemoto M, Tsujimura K, Kondo T, Matsumura T.In horse populations, influenza A virus subtype H3N8 (equine influenza virus, EIV) is a very important pathogen that leads to acute respiratory disease. Recently, EIV has emerged in dogs, and has become widespread among the canine population in the United States. The interspecies transmission route had thus far remained unclear. Here, we tested whether the interspecies transmission of EIV to dogs could occur as a result of close contact with experimentally EIV-infected horses. Three pairs consisting of an EIV-infected horse and a healthy dog were kept together in individual stalls for 15 conse...
Daly JM, Yates PJ, Newton JR, Park A, Henley W, Wood JL, Davis-Poynter N, Mumford JA.Two lineages of antigenically distinct equine influenza A H3N8 subtype viruses, American and European, co-circulate. Experiments were conducted in ponies to investigate the protection induced by vaccines containing virus from one lineage against challenge infection with homologous or heterologous virus. Regression analysis showed that vaccinated ponies with average pre-challenge single radial haemolysis (SRH) antibody levels (i.e. 45-190mm2) had a higher probability of becoming infected if they were vaccinated with virus heterologous to the challenge strain than if they were vaccinated with ho...
Tumova B, Easterday BC.This study demonstrates relationships in envelope antigens of 4 human influenza A2 strains isolated during the period 1957-68 (including A2/Hong Kong/68), 2 strains of A/Equi-2/63 and 7 avian influenza viruses isolated in Europe, North America, and the Ukraine in the years 1960-67.Antigenic relationships among the strains were determined on the basis of haemagglutination-inhibition, virus-neutralization, strain-specific complement-fixation, and neuraminidase-inhibition tests.North American avian influenza strains, Turkey/California/64, Turkey/Massachusetts/65, Turkey/Wisconsin/66, Turkey/Ontar...
Nakamura Y, Kishi M, Nakaya T, Asahi S, Tanaka H, Sentsui H, Ikeda K, Ikuta K.Borna disease (BD) is a progressive poliomeningoencephalomyelitis which occurs naturally in horses and sheep. Here, peripheral blood mononuclear cells (PBMC) derived from 57 healthy horses in Japan were examined by a nested reverse transcription-polymerase chain reaction to determine the prevalence of BD virus (BDV) infection. Seventeen (29.8%) of the samples were positive by this examination and the specificity of the amplified product was confirmed by hybridization with authentic oligomer probes. About 60% of the BDV RNA-positive individuals also showed seropositivity by Western blotting. Th...
Quirin R, Salas M, Zientara S, Zeller H, Labie J, Murri S, Lefrançois T, Petitclerc M, Martinez D.To determine whether West Nile virus (WNV) had reached the archipelago of Guadeloupe, a serologic study in horses and birds was conducted in 2002. Immunoglobulin (Ig) G, IgM, enzyme-linked immunosorbent assay, and seroneutralization tests identified WNV infection in horses and chickens. Six months later, a high rate of seroconversion was observed in horses.
Turtinen LW, Allen GP, Darlington RW, Bryans JT.The molecular and serologic relatedness of 2 recent respiratory tract isolates of equine herpesvirus type 1, designated T1 and T2, were compared with the Army 183, Kentucky-A hamster-adapted (KyA-ha), and L-M cell-adapted (KyA-LM) strains. Electrophoresis in polyacrylamide gels revealed differences in virion structural proteins among 4 purified strains. Seven envelope glycoproteins (molecular weight of 93,000, 65,000, 62,000, 60,000, 36,000, 20,000, and 18,000) corresponding to virion proteins 13, 16, 17, 18, 23, 25, and 26a, respectively, found in both the Army 183 and KyA-ha strains had slig...
Ludwig H, Thein P.From 18 horses with clinical symptoms of an affection of the central nervous system and with histopathologic alterations in the brain, four were demonstrated to have Bornavirus-specific antibodies. The antibodies are monospecific, recognizing identical antigens from infected brains of different animal species as well as from persistently infected tissue culture cells. Discrete immunoglobulin species (oligoclonal IgG) can be demonstrated in concentrated horse cerebrospinal fluid; they carry Bornavirus antibody specificity. Their presence, together with the higher antibody titers in the cerebros...
Rockstroh A, Moges B, Berneck BS, Sattler T, Revilla-Fernández S, Schmoll F, Pacenti M, Sinigaglia A, Barzon L, Schmidt-Chanasit J, Nowotny N....Tick-borne encephalitis virus (TBEV) and West Nile virus (WNV) are important arthropod-borne zoonotic flaviviruses. Due to the emergence of WNV in TBEV-endemic regions co-circulation of both viruses is increasing. Flaviviruses are structurally highly similar, which leads to cross-reacting antibodies upon infection. Currently available serological assays for TBEV and WNV infections are therefore compromised by false-positive results, especially in IgG measurements. In order to discriminate both infections novel diagnostic methods are needed. We describe an ELISA to measure IgG antibodies specif...
Blakeslee JR, Olsen RG, McAllister ES, Fassbender J, Dennis R.Five horses were experimentally exposed to equine herpesvirus 2 strain LK. Two young foals developed chronic pharyngitis (98 and 232 days, respectively). Growth characteristics, cytopathic effects (CPE), inclusion body formation, ether sensitivity, and immunofluorescent analysis indicated that the virus recovered from infected animals was a herpesvirus serologically identical with, or at least antigenically related to EHV-2 strain LK. No significant complement-fixing (CF) or virus-neutralizing (VN) antibody responses were observed in adult horses while both foals demonstrated a rise in CF anti...
Ward MP, Schuermann JA, Highfield LD, Murray KO.Equine West Nile virus (WNV) encephalomyelitis cases - based on clinical signs and ELISA serology test results - reported to Texas disease control authorities during 2002 were analyzed to provide insights into the epidemiology of the disease within a previously disease-free population. The epidemic occurred between June 27 and December 17 (peaking in early October) and 1,698 cases were reported. Three distinct epidemic phases were identified, occurring mostly in southeast, northwest and then central Texas. Significant (P<0.05) disease clusters were identified in northwest and northern Texas. M...
Hirota J, Nishi H, Matsuda H, Tsunemitsu H, Shimiz S.Flavivirus-infected sera are known to show cross-reactions in serodiagnoses of heterologous flavivirus infections. Japanese encephalitis virus (JEV) is endemic in Asia and, in Japan, many horses are vaccinated against JEV. However, the cross-reactivity level of JEV-vaccinated horse sera in the serodiagnosis of West Nile virus (WNV) has not been clarified. The antibody cross-reactivity of JEV-vaccinated horse sera in WNV serological tests, such as the plaque reduction neutralization test (PRNT), IgG indirect ELISA (IgG-ELISA) and hemagglutination inhibition (HI) test, was examined. All JEV-vacc...
Magnarelli LA, Ijdo JW, Van Andel AE, Wu C, Padula SJ, Fikrig E.To determine whether horses living in tick-infested areas of northeastern United States with clinical signs of borreliosis or granulocytic ehrlichiosis had detectable serum antibodies to both Borrelia burgdorferi and Ehrlichia equi. Methods: Prospective study. Methods: Serum samples from 51 clinically normal horses, 14 horses with clinical signs of borreliosis, and 17 horses with clinical signs of granulocytic ehrlichiosis. Methods: Serum B burgdorferi or E equi antibodies were measured by use of an ELISA, immunoblot analysis, or indirect fluorescent antibody (IFA) staining. Results: Of the 82...
Shi N, Qiu X, Cao X, Mai Z, Zhu X, Li N, Zhang H, Zhang J, Li Z, Shaya N, Lu H, Jin N.The Getah virus (GETV), a mosquito-borne RNA virus, is widely distributed in Oceania and Asia. GETV is not the only pathogenic to horses, pigs, cattle, foxes and boars, but it can also cause fever in humans. Since its first reported case in Chinese mainland in 2017, the number of GETV-affected provinces has increased to seventeen till now. Therefore, we performed an epidemiologic investigation of GETV in the Xinjiang region, located in northwestern China, during the period of 2017-2020. ELISA was used to analyze 3299 serum samples collected from thoroughbred horse, local horse, sheep, goat, ca...
