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.
Valderrama-Martinez C, Packham A, Smith W, Mendoza-Flores JE, Zheng S, Chigerwe M, Plancarte M, Aleman M.Long-term freezing storage can alter the stability of proteins, thereby compromising accurate determination of indirect fluorescent antibody test (IFAT) titers that support the diagnosis of equine protozoal myeloencephalitis. Objective: Assess the effect of long-term storage at -80°C on IFAT against S. neurona and N. hughesi in equine serum and cerebrospinal fluid (CSF). Methods: Paired serum and CSF (n = 46), and serum only (n = 25) samples. Methods: Prospective study of samples stored 6-12, 13-18, and 19-24 months. Comparing antibody titers across time points, McNemar and Wilcoxon...
Nemoto M, Kawanishi N, Kamei R, Furusho K, Kawauchi K, Yabuuchi Y, Oue Y, Uchida Y, Nishiura H, Reedy SE, Chambers TM, Li F, Bannai H, Yamanaka T....In April and May 2025, outbreaks of equine influenza occurred for the first time in 17 years in Japan. Equine influenza virus (EIV) of the H3N8 subtype was mainly detected in heavy draft horse populations in Kumamoto Prefecture and the Tokachi area of Hokkaido. In total, 10 EIVs were isolated from infected horses and then were used for genetic and serological analyses. Phylogenetic analysis of all eight genes revealed that all Japanese isolates were clustered with the Florida sublineage clade 1 (Fc1) viruses and were closely related to North American Fc1 viruses detected in 2024-2025. The resu...
Şahinkesen İ, Bilge-Dağalp S.Equine herpesvirus 1 (EHV-1) and Equine herpesvirus 4 (EHV-4) are major viral pathogens of horses that contribute to respiratory disease, abortion, and neurological disorders, leading to economic losses in the equine industry. Accurate serological diagnosis is critical for disease surveillance and control. This study aimed to develop and validate an in-house enzyme-linked immunosorbent assay (ELISA) for detecting antibodies against EHV-1 and EHV-4 in horse sera. Serum samples previously confirmed by virus neutralization test (VNT) and a commercial ELISA were used to optimize the assay. Cut-off...
Yang Y, Guo K, Xu L, Guo W, Dong M, Liu W, Li S, Zhang Z, Chu X, Wang Y, Zhang Z, Hu Z, Wang X.Equine influenza (EI), caused by the equine influenza virus (EIV), is an acute respiratory disease that has become enzootic worldwide, resulting in frequent outbreaks and substantial economic losses within the equine industry. In this study, we developed a competitive enzyme-linked immunosorbent assay (NP-cELISA) for the detection of antibodies against the EIV nucleoprotein (NP). The assay was designed by coating plates with purified monoclonal antibodies (mAbs) against the NP protein, followed by simultaneous incubation of the test serum samples and HRP-NP antigen in a competitive binding rea...
Chinyere CN, Ajaebili AC, Peter-Ajuzie IK, Galadima HB, Daodu OB, Fatola OI, Okolo CC, Alaba BA, Akinniyi OO, Omoniwa DO, Edeh ER, Olorunfemi AB....African horse sickness (AHS) is a severe, infectious arthropod-borne disease of equids caused by the AHS virus (AHSV). It is endemic in Sub-Saharan Africa, and several sporadic outbreaks of the disease have been reported in Nigeria in the past 5 decades. Following a recent outbreak of the disease in Lagos State, this study was conducted to investigate the prevalence of (AHSV) antibodies in apparently healthy horses and some selected wildlife sampled in four geographical regions of Nigeria. Using a competitive enzyme-linked immunosorbent assay, 575 serum samples collected from horses in five ...
Janshoff S, Plümers R, Ramsauer AS, Cavalleri J, Vollmer T, Todt D, Brown RJP, Steinmann E, Gömer A.The emergence of new pathogens poses a significant threat to global health, exacerbated by climate change, biodiversity loss, and increased globalization. Ticks, as vectors for various pathogens, contribute to the rising incidence of diseases. Surveillance programs are crucial for identifying and controlling emerging pathogens. This study focuses on the Alongshan virus (ALSV), a segmented flavi-like virus first identified in humans in China in 2017. Despite its ability to infect a wide range of mammals, the natural hosts and transmission pathways of ALSV remain poorly understood. Therefore, we...
Badr C, Arbi M, Souiai O, Larbi I, Nsiri J, Elbehi I, Bouslama Z, Bennour MA, Essaied MS, Ines Khosrof , Chabchoub A, Ben Aoun B, Ghram A, Lachheb J.Equine influenza (EI) is a highly contagious viral respiratory disease affecting equids, with the potential of causing widespread outbreaks across Europe, the Americas, Asia, and other regions of the world. In Tunisia, in the spring of 2021, an EI virus outbreak occurred in a farm housing purebred Arabian horses that exhibited respiratory signs. This outbreak led to a national lockdown on horse movements and the cancellation of equestrian events. A total of 432 serum samples, collected from 2018 to 2021, were tested using ELISA competition assay. In addition, 100 Nasal swabs were collected dur...
Tinarwo M, Dennis SJ, Hitzeroth II, Meyers AE, Rybicki EP, Mbewana S.African horse sickness (AHS) is a severe, noncontagious disease of equines caused by the African horse sickness virus (AHSV). The virus has nine serotypes and is transmitted by the midge. AHS is endemic in South Africa and other sub-Saharan African countries. Currently, the disease is managed using a live attenuated vaccine manufactured by Onderstepoort Biological Products (OBP). Although this vaccine has been in use for decades, it has several drawbacks, including the possibility of reversion to virulence, and it does not allow for the differentiation of infected horses from vaccinated horse...
Schwarzer A, Ziegler U, Fertey J, Kreuz M, Vahlenkamp TW, Groschup MH, Ulbert S.West Nile virus (WNV), Usutu virus (USUV) and tick-borne encephalitis virus (TBEV) are worldwide endemic zoonotic orthoflaviviruses, often co-circulating in the same areas. Serological studies in animals, mostly birds and horses, are important means to monitor the spread of these viruses and the infection risks for humans. However, cross-reactive antibodies to these structurally similar flaviviruses frequently impact serological differentiation in enzyme-linked immunosorbent assays (ELISAs), hence time-consuming virus neutralization tests (VNTs) have to be employed in laboratories with high bi...
Imandar M, Javadi A, Abdollahpour G, Mahale PRS, Qanbari A, Mirzaalimohammadi M, Taherkhani E, Olfatifar M, Nikkhahi F, Eslahi AV, Badri M.Leptospirosis, a global zoonotic disease caused by pathogenic Leptospira spp., poses significant health risks to both animals and humans. This study aimed to assess the seroprevalence of antibodies against Leptospira interrogans serovars in stabled horses in Qazvin province, Northwest Iran. From January 2023 to April 2024, a total of 83 blood samples were collected from asymptomatic horses using the microscopic agglutination test (MAT). Results indicated a seroprevalence of 40.96% (95% CI: 31-52), with notable variations among regions: 38.89% (95% CI: 27-52) in Qazvin, 38.46% (95% CI: 18-64) i...
Busquets N, Gardela J, José-Cunilleras E, Solé A, Salvador MJ, Obón E, Molina-López R, Aranda C, Montalvo T, Corbella I, Bou-Monclús MA....West Nile virus (WNV), mainly transmitted by mosquitoes, poses significant health risks to humans and horses, particularly in endemic regions. The first detection of WNV lineage 2 in Spain was in 2017 in Catalonia (northeastern Spain). In 2023, WNV was confirmed in a young yellow-legged gull and a probable human case was notified within the urban settings. We aimed to define the zone of WNV circulation in the Barcelona Metropolitan Area where these infections occurred and the effectiveness of the One Health approach for early WNV detection. The Catalan WNV surveillance and control programs in...
Kukurić T, Erdeljan M, Matthews JB, Lightbody KL, Austin CJ, Peczak N, Uzelac A, Klun I, Simin S. spp. are common equine tapeworm species in Europe, frequently found in grazing horses. is the most pathogenic, clinically significant species associated with gastrointestinal disorders, particularly colic, and can have a fatal outcome in some horses. The aim of this study was to determine the infection prevalence of spp. in Serbia and to identify relevant risk factors. A total of 173 horses from various regions were tested using a combination of diagnostic methods: coprological analysis via combined sedimentation-flotation and the Mini-FLOTAC technique, as well as serological testing using ...
Gonzalez-Obando J, Jaimes-Dueñez J, Zuluaga-Cabrera A, Forero JE, Diaz A, Rojas-Arbeláez C, Ruiz-Saenz J.Equine influenza is a highly contagious disease caused by the equine influenza virus (EIV). The occurrence of EIV outbreaks in America is associated with low levels of vaccination coverage. In Colombia, no seroprevalence evaluation has been carried out to estimate the distribution of the virus within the country. Our aim was to perform a sero-epidemiological survey of equine influenza infections and to identify associated risk factors in horses from four departments of Colombia. Serological testing was carried out by using an ELISA for the detection of IgG antibodies against the influenza A vi...
Duaso J, Perez-Ecija A, Navarro A, Martínez E, De Las Heras A, Mendoza FJ.Equine piroplasmosis (EP) is an endemic parasitic disease in southern European countries, such as Spain. Andalusia, the most southwestern region of Europe, is the community with the highest number of registered horses and farms in Spain and one of the main international exporters of Andalusian (Spanish Purebred) horses worldwide. Considering the current expansion of this disease and the possible effect of climate change on its prevalence, studying the EP prevalence in this region is compelling. Molecular (PCR) and serological methods (cELISA and IFAT) were used to study the true and apparent p...
Crisman EC, Furr M, Ramachandran A.To determine the seroprevalence of Francisella tularensis in horses in Oklahoma and to describe factors associated with seropositivity. Unassigned: In this observational study, 238 frozen equine serum samples were tested for F tularensis by microagglutination assay (MAT). Samples were collected from 36 of 77 Oklahoma counties from 2021 through 2023. Exclusion criteria included insufficient sample quantity, cross-reactivity to Brucella abortus, and county outside of Oklahoma. The Fisher exact test was used to compare the proportion of positive tests by year, river basin, and topographic region....
Picanço EMB, Assis FFV, Peleja PL, Sousa ABB, Barrêto Júnior RA, Lima RF, Neves KAL, Minervino AHH.This study aimed to determine the prevalence of antibodies against equine brucellosis in three distinct equid groups (farm animal, urban carthorse, and sport horse) in Western Pará, Brazil, and to identify associated risk factors. A cross-sectional study, involving 75 farms across 14 municipalities, sampled 1069 equids composed of urban carthorses and sport horses. Serum samples were tested for antibodies against spp. using the buffered acidified plate antigen (BAPA) test for screening, followed by the serum agglutination in tubes with 2-mercaptoethanol (2-ME) for confirmation. Univariate an...
Sousa JA, Miranda LM, Coutinho DJB, Costa TF, Costa SP, Freitas ÚS, Costa FB, Machado RZ, Nogueira RMS, Costa APD.The hemoprotozoan Trypanosoma evansi is a parasite that infects mammals, causing an infection known as trypanosomiasis. There is no report of T. evansi in horses in the State of Maranhão, highlighting the need to assess exposure and infection by the parasite and generate data for its monitoring. The objectives of this study were to identify T. evansi in blood samples from horses, investigate its occurrence in horses in this region, and analyze the associated risk factors. Three hundred blood samples were collected for parasitological (blood smear), serological (indirect enzyme-linked immunoso...
Tolnai CH, Forgách P, Marosi A, Fehér O, Paszerbovics B, Tenk M, Wagenhoffer Z, Kutasi O.In the last three decades, West Nile virus (WNV, Flaviviridae, Orthoflavivirus genus) has become one of the most important encephalitic agents worldwide, causing substantial numbers of cases in humans and horses every year by re-emerging in endemic areas and emerging in new territories. It is considered that after natural WNV infection, humans and birds develop long-term immunoprotection, but data on immunoprotection in horses is scarce. Objective: West Nile virus infection provides long-term humoral immunity in subclinically infected horses. Methods: Client-owned, naturally WNV subclinically ...
Ostuni A, Frontoso R, Crudele MA, Barca L, Amati M, Boni R, De Vendel J, Raimondi P, Bavoso A.Equine Infectious Anemia Virus (EIAV), a lentivirus marked by considerable genetic variability, poses significant diagnostic challenges. Existing diagnostic tools encompass the Agar Gel Immunodiffusion Assay (AGID), enzyme-linked immunosorbent assay (ELISA), and Western blotting (WB). ELISA and AGID mainly utilize the p26 capsid protein, often sourced from the Wyoming reference strain. To broaden the range of viral proteins and strains employed in these immunoassays, we previously developed a novel p26/double-strain gp45 indirect ELISA. In this study, we evaluated the performance of this ELISA...
Firdausy LW, Fikri F, Wicaksono AP, Çalışkan H, Purnama MTE.Equine infectious anemia (EIA) is a lentiviral disease affecting members of the Equidae family, with global distribution and significant implications for animal health and biosecurity. Despite numerous individual reports, a comprehensive synthesis of its global prevalence and risk factors remains lacking. This study aimed to conduct a systematic review and meta-analysis to estimate the global prevalence of EIA, identify diagnostic trends, and evaluate factors associated with heterogeneity across studies. Unassigned: A systematic search was conducted in six major databases (PubMed, Scopus, Web ...
Abbas I, Ahmed F, Muqaddas H, Alberti A, Varcasia A, Sedda L.Climate change can cause spatio-temporal shifts in the epidemiology of various vector borne pathogens, especially in vulnerable areas such as the Mediterranean Basin (MB). Among these pathogens, the West Nile virus (WNV) became endemic in the region. This systematic review and meta-analysis study summarizes WNV epidemiology, molecular characteristics, and surveillance in various MB countries, relying on data and scientific articles on WNV published during 2010-2023. The number of published articles varied across the three MB subregions: Southern Europe (n = 153), North Africa (n = 33), and...
Al-Rammahi HM, Mohsen RK, Othman RM.West Nile virus (WNV) circulates between birds and mosquitoes, with horses and humans as incidental dead-end hosts. Despite documented cases in neighboring countries and human cases in southern Iraq, no previous studies have investigated WNV in Iraqi horses. Unassigned: To determine the seroprevalence of WNV in horses from three southern Iraqi governorates (Thi-Qar, Misan, and Basrah) between March and June 2024. Unassigned: Blood samples were collected from 236 horses regardless of age, sex, or health status. Serum samples were analyzed using commercial competitive enzyme-linked immunosorbent...
Franco JJ, Gonzálvez M, Cano-Terriza D, Barbero-Moyano J, Jose-Cunilleras E, Alguacil E, García J, García-Bocanegra I.Equine viral arteritis is a notifiable infectious disease with sanitary and economic implications at a global scale. A cross-sectional serosurvey was performed to determine the exposure of equids to the Alphaarterivirus equid [Equine Arteritis Virus (EAV)] in three regions in western Europe. Serum samples from 1425 equids (1196 horses, 104 donkeys, and 125 mules/hinnies) from Catalonia (northeastern Spain), Andalusia (southern Spain) and southeastern United Kingdom (UK) were collected during the period 2011-2023. The overall EAV seroprevalence in EAV-unvaccinated equids was 9.7 % (138/1425; 9...
Elmahallawy EK, Hassan MF, Cano-Terriza D, Albalawi NO, Fajardo T, Gouda AA, Atiba A, Hendawy A, Villena I, Barakat AM, Alzaylaee H, Almería S....Toxoplasmosis, caused by the intracellular protozoan (), continues to be a widespread parasitic zoonotic disease globally. The seroepidemiology of infection in Egyptian equids, particularly donkeys, remains insufficiently explored. The present study was designed to assess the seroprevalence of in equines from Northern Egypt. Unassigned: A total of 360 serum samples from two equine species (157 horses and 203 donkeys) were obtained during 2023. The Modified Agglutination Test (MAT, cut-off of 1:25) was used to screen for the anti- antibodies. The study also analyzed potential risk factors th...
Punyadarsaniya D, Taesuji M, Rattanamas K, Ruenphet S.Standard serological tests post-vaccination, such as enzyme-linked immunosorbent assay (ELISA), complement fixation, and virus neutralization, are crucial for monitoring African horse sickness (AHS). However, the availability of commercial test kits such as blocking ELISA varies by regions; while they are commonly used in Africa and Europe, their limited availability and high cost in Thailand present significant challenges. Therefore, this study aimed to evaluate an alternative approach using an in-house indirect ELISA based on cell-based monovalent and polyvalent strains of live attenuated AH...
Pinho APVB, Ferreira F, Fuck JJ, de Oliveira JP, Dias RA, Grisi-Filho JHH, Heinemann MB, Telles EO, Amaku M, Ferreira Neto JS.Considering that control strategies for Equine Infectious Anemia, based on the serological diagnosis of equids and the removal of positive animals, may not be optimal for developing countries with an absolute predominance of grade working animals, this study aimed to address this issue based on the epidemiological situation of the disease in Pará, a state in the Brazilian Amazon. Pará was divided into five regions, and within each region a pre-established number of farms were randomly selected. Within each farm, a pre-set number of animals were randomly selected and submitted to Agar Gel Imm...
Serpa PBS, Bogers S, Byron C, Cardona G, Patton M.A 1-year-old American Quarter horse was presented with acute onset of right hind lameness. On physical examination, there was synovial effusion of the right tarsocrural joint. Synovial fluid cytology revealed a marked eosinophilic synovitis. Serology indicated evidence of acute and chronic infection with Borrelia burgdorferi, although PCR of the synovial fluid was negative. The filly was treated with phenylbutazone and oxytetracycline, and repeated synovial cytology indicated improvement. The filly was discharged with a prescription of minocycline for 30 days. Despite initial improvement, recu...
Pádua GT, Tavares MA, de Lima NJ, Paula WVF, Dos Santos GC, Neves LC, Bittencourt RBM, Paludo RLDR, Cardoso ERN, da Silva BBF, Pádua BR....This study sought to investigate the presence of anti- spp. antibodies in georeferenced serum samples from equids across all regions of the state of Goiás, while also presenting variables that indicate risk factors for the circulation of rickettsiae, and evaluating the presence of rickettsial DNA in ticks collected from equids and the surrounding environment in the municipalities of Uruaçu and Porangatu, located in the northern region of the state. A total of 1156 equid serum samples provided by the Goiás Agricultural Defense Agency (Agrodefesa) were analyzed for antibodies against 4 antig...
Chevalier N, Migné CV, Mariteragi-Helle T, Dumarest M, De Mas M, Chevrier M, Queré E, Marcillaud-Pitel C, Lupo C, Bigeard C, Touzet T, Leblond A....The circulation of West Nile virus (WNV), Usutu virus (USUV), and tick-borne encephalitis virus (TBEV) was investigated in south-western France during the first six months of 2023, following the emergence of WNV in equids in Gironde, a département in south-western France, in 2022. Blood samples were collected from 494 horses located in the Gironde département and divided into three zones: the Confluence zone, the Intermediate zone and the Arcachon Basin. Samples were tested for WNV-, USUV- and TBEV-specific antibodies. An overall seroprevalence of 14% (95% CI [11-18%]) for orthoflavivirus an...
Domínguez-Odio A, González LIC, Alfonso DM, Guevara-Hernández F, La O Arias MA, Zayas MP, Ríos MÁB.The transmembrane glycoprotein gp45 (implicated in virus-equine B lymphocyte binding and in subsequent infection) is an important protein used as an antigen in the serological diagnosis of equine infectious anemia, but synthetic peptides derived from its structure are not. Consequently, the present study aimed to determine the diagnostic performance of the Bio-AIELAB immunoassay (novel synthetic peptide P05/gp45) in comparison with a similar commercial assay (ELISA EIA, VMRD Inc, USA) and with the gold standard (AGID, LABIOFAM, Cuba). A total of 365 samples of sera from naturally infected Cuba...
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...
Oue Y, Morita Y, Kondo T, Nemoto M.Equine coronavirus (ECoV) outbreaks have occurred three times at Obihiro Racecourse in Hokkaido, Japan. The third ECoV outbreak occurred between late February and early April 2012. The main clinical signs of affected horses were anorexia, pyrexia and leucopenia; gastrointestinal disease was observed in about 10% of affected horses. Two ECoV strains were isolated from diarrheal samples. All paired sera (9/9) collected from febrile horses showed seroconversion by neutralization test. Sequence and phylogenetic analysis of the ECoV isolated showed that putative amino acid sequences in S and N gene...
Kutasi O, Bakonyi T, Lecollinet S, Biksi I, Ferenczi E, Bahuon C, Sardi S, Zientara S, Szenci O.The spread of lineage 2 West Nile virus (WNV) from sub-Saharan regions to Europe and the unpredictable change in pathogenicity indicate a potential public and veterinary health threat and requires scientific awareness. Objective: To describe the results of clinical and virological investigations of the 1st outbreak of a genetic lineage 2 WNV encephalomyelitis in horses. Methods: Seventeen horses with neurologic signs. Methods: Information regarding signalment, clinical signs, and outcome was obtained for each animal. Serology was performed in 15 cases, clinicopathological examination in 7 case...
Osawa S, Furuse K, Watanabe I.To determine the distribution pattern of ribonucleic acid (RNA) coliphages (classified by serological groups I through IV) in animal sources, we isolated RNA phages from (i) feces samples from domestic animals (cows, pigs, horses, and fowls), some other animals in a zoological garden, and humans, (ii) the gastrointestinal contents of cows and pigs, and (iii) sewage samples from treatment plants in slaughter houses. These samples were then analyzed serologically. The concentration of RNA phages in the first and second kinds of material was fairly low (10 to 10(3) plaque-forming units per origin...
Cerri D, Ebani VV, Fratini F, Pinzauti P, Andreani E.Serological data on leptospira infection were reported and discussed. From 1995 to 2001, the blood serum samples of 9885 domestic and wild animals and humans, living in Northern and Central Italy, were examined by the macroagglutination test (MAT) employing bratislava, ballum, canicola, grippotyphosa, icterohaemorrhagiae, pomona, hardjo and tarassovi serovars as antigens. Considering sera with > or = 1:400 antibody titers as positive, 674 (6.81%) animals scored positive. Sheep, horses, pigs and dogs gave the highest number of positive responses, particularly against the serovar bratislava and,...
Richt JA, Pfeuffer I, Christ M, Frese K, Bechter K, Herzog S.The geographic distribution and host range of Borna disease (BD), a fatal neurologic disease of horses and sheep, are larger than previously thought. The etiologic agent, Borna disease virus (BDV), has been identified as an enveloped nonsegmented negative-strand RNA virus with unique properties of replication. Data indicate a high degree of genetic stability of BDV in its natural host, the horse. Studies in the Lewis rat have shown that BDV replication does not directly influence vital functions; rather, the disease is caused by a virus-induced T-cell mediated immune reaction. Because antibodi...
M'ghirbi Y, Yaïch H, Ghorbel A, Bouattour A.Anaplasma phagocytophilum , the causative agent of granulocytic anaplasmosis, affects several species of wild and domesticated mammals, including horses. We used direct and indirect methods to compare and evaluate exposure to A. phagocytophilum in horses in northern Tunisia. Methods: Serum from 60 horses was tested by IFA for antibodies to A. phagocytophilum , and whole blood was tested for A. phagocytophilum 16S rRNA gene using a nested-PCR. To examine the risk of A. phagocytophilum transmission, 154 ticks that had been collected from horses were examined for the presence of A. phagocytophilu...
Virmani N, Bera BC, Singh BK, Shanmugasundaram K, Gulati BR, Barua S, Vaid RK, Gupta AK, Singh RK.An outbreak of equine influenza (EI) was reported in India in June, 2008 after a gap of two decades. The outbreak started from Jammu and Kashmir (Katra), northern state of India and spread to the other parts of the country affecting equines in 11 states. The virus (H3N8) was isolated from nasal swabs obtained from clinical cases in various locations in the country including Katra (Jammu and Kashmir), Mysore (Karnataka) and Ahmedabad (Gujarat) using embryonated chicken eggs. The virus isolates were identified as H3N8 by haemagglutination inhibition (HI) test titration with standard serum and by...
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 ...
Heim A, Passos LM, Ribeiro MF, Costa-Júnior LM, Bastos CV, Cabral DD, Hirzmann J, Pfister K.Blood samples were collected from 487 adult horses, including 83 pregnant mares, at a slaughterhouse located in Araguari, Minas Gerais State, Brazil. For each blood sample, the packed cell volume (PCV) was determined, and Giemsa-stained smears were microscopically examined for the presence of hemoparasites. The plasma was examined by the indirect fluorescent antibody test for detection of antibodies against Babesia caballi and Theileria equi. In addition, DNA was extracted and analyzed by a multiplex real-time polymerase chain reaction (PCR), specific for B. caballi and T. equi. Products of PC...
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...
Wang H, Liu KJ, Sun YH, Cui LY, Meng X, Jiang GM, Zhao FW, Li JJ.Salmonella enterica subspecies enterica serovar abortus equi (S. abortus equi) is well known as the aetiological agent of equine abortion. However, abortion caused by S. abortus equi has not been previously described in donkeys. Objective: To investigate whether S. abortus equi was correlated with an abortion outbreak consisting of 61 abortions. Methods: Investigation of the clinical cases using pathoanatomical, bacteriological, serological and molecular approaches. Methods: Autopsies on nine aborted foetuses were performed. Tissue specimens from seven aborted foetuses and two mares were cu...
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...
Grause JF, Ueti MW, Nelson JT, Knowles DP, Kappmeyer LS, Bunn TO.Theileria equi, one of the causative agents of equine piroplasmosis, is endemic in many regions of the world but is considered a 'foreign' animal disease in the USA. In an effort to prevent the importation of T. equi, stringent serological screening of horses is practiced prior to entry to the USA. Current regulatory options available where horses are found to be infected include permanent quarantine with or without chemotherapy, repatriation, or euthanasia. Chemotherapeutics that eliminate infection and subsequently transmission risk are critical in the management of infected horses. In this ...
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...
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 ...
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...
Proudman CJ, French NP, Trees AJ.The association between the equine intestinal tapeworm Anoplocephala perfoliata and specific types of intestinal disease was investigated by matched case-control study using coprological and serological diagnosis. We have previously shown that the host IgG(T) response to 12/13 kDa antigens of A. perfoliata correlates well with infection intensity, therefore this antibody response was used to investigate the risk of colic at different levels of parasite infection intensity. One hundred and three spasmodic colic cases with an equal number of controls matched for age, breed and gender, and 20 ile...
Pinto PS, Libonati H, Lilenbaum W.Leptospirosis is a worldwide zoonosis which can affect many species. Control programs need accurate diagnosis to be successful, and currently, diagnosis relies on serology. It presents three main issues: the sampling, the antigen panel, and the cutoff point. Herein, we propose a systematic review on leptospirosis among dogs, pigs, and horses in Latin America in order to improve the understanding of the seroepidemiology of leptospirosis in these species in the region as well as the temporal development of the research on this topic and, consequently, improve the chances of success on control pr...
Hansen MG, Christoffersen M, Thuesen LR, Petersen MR, Bojesen AM.Borrelia burgdorferi sensu lato and Anaplasma phagocytophilum are able to infect horses. However, the extend to which Danish horses are infected and seroconvert due to these two bacteria is unknown. The aim of the present study was to evaluate the seroprevalence of B. burgdorferi sensu lato and A. phagocytophilum in Danish horses. Methods: A total of 390 blood samples collected from all major regions of Denmark and with a geographical distribution corresponding to the density of the Danish horse population were analyzed. All samples were examined for the presence of antibodies against B. burgd...
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...
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...
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...
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 ...
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...
Rocha T, Ellis WA, Montgomery J, Gilmore C, Regalla J, Brem S.A bacteriological survey of kidneys from 145 abattoir horses was performed, which resulted in the isolation of two Leptospira strains. The isolates were serologically typed as belonging to serogroups Australis and Pomona, and REA identified them as L. interrogans serovar Bratislava and L. kirschneri serovar Tsaratsovo, respectively. These are the first Leptospira isolates obtained from horses in Portugal and the Bratislava strain is the first serogroup Australis strain to be isolated in this country. The 145 horses were also serologically tested for leptospiral antibodies, and 37% had MAT titr...
Carrera JP, Bagamian KH, Travassos da Rosa AP, Wang E, Beltran D, Gundaker ND, Armien B, Arroyo G, Sosa N, Pascale JM, Valderrama A, Tesh RB....Members of the genera (family ) and (family ) are important zoonotic human and equine etiologic agents of neurologic diseases in the New World. In 2010, an outbreak of Madariaga virus (MADV; formerly eastern equine encephalitis virus) and Venezuelan equine encephalitis virus (VEEV) infections was reported in eastern Panamá. We further characterized the epidemiology of the outbreak by studying household contacts of confirmed human cases and of equine cases with neurological disease signs. Serum samples were screened using a hemagglutination inhibition test, and human results were confirmed u...
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...
