Infections in horses encompass a range of diseases caused by various pathogens, including bacteria, viruses, fungi, and parasites. These infections can affect different systems within the horse, such as the respiratory, gastrointestinal, and integumentary systems, leading to a variety of clinical signs depending on the pathogen and the severity of the infection. Common infectious diseases in horses include equine influenza, strangles, and equine herpesvirus. Diagnosis often involves clinical examination, laboratory testing, and sometimes imaging, to identify the causative agent and assess the extent of the disease. Treatment strategies may include antimicrobial therapy, supportive care, and preventive measures such as vaccination and biosecurity practices. This page aggregates peer-reviewed research studies and scholarly articles that explore the pathogenesis, diagnosis, treatment, and prevention of infectious diseases in equine populations.
Baptiste KE, Kyvsgaard NC, Ahmed MO, Damborg P, Dowling PM.Rifampin is an enigma among antimicrobials. Blood and tissue compartment concentrations are a "moving target" along the treatment course due to the complex pharmacodynamic interactions within the body. Rifampin concomitant therapies are for the prevention and treatment of Rhodococcus equi infection in foals, for nearly 40 years. The necessity of rifampin concomitant therapies is based on beliefs that both antimicrobials (e.g., rifampin plus macrolide) penetrate into pulmonary abscesses and intracellular compartments above R. equi minimum inhibitory concentrations (MICs), as well as better ef...
Hoxha I, Xhekaj B, Muja-Bajraktari N, Sekulin K, Unterköfler MS, Schlamadinger L, Situmorang T, Fuehrer HP, Obwaller AG, Camp JV, Walochnik J....West Nile virus (WNV, family Flaviviridae) is the most geographically widespread arbovirus affecting humans. It circulates between wild birds and mosquitoes, while humans and horses are dead-end hosts. In recent years, several outbreaks have been reported from European countries, including the Balkan Peninsula. In the Republic of Kosovo, a southern Balkan country, data on WNV are scarce, and neither mosquito monitoring nor WNV surveillance is established. To address this gap, we aimed to assess a first monitoring approach that should set the basis and support future large-scale activities in t...
Bai B, Zhang X, Zhang M, Ma W, Li J, Zhang H, Na L, Guo X, Lin Y, Wang XF, Wang X.Equine infectious anemia virus (EIAV) is an important model for the study of pathogenesis in lentiviruses. Studies of viral genome organization and replication mechanisms are fundamental to the understanding of virus pathogenicity. In this study, we identified an unique transcript from EIAV in vivo and in vitro by Sanger sequencing and Northern blotting. The transcript contains a complete open reading frame and has length 369 nt. We named the protein encoded by this transcript S4 and demonstrated its expression in EIAV-infected cells. An S4-deficient EIAV infectious clone displayed obviously i...
Sosa-Portugal S, Dale L, Devaney J, Sharp A, Malalana F, Timofte D.The "ESKAPE" bacteria include a group of organisms known for their multidrug resistance and potential association with nosocomial infections in human and veterinary hospitals. Objective: This study aimed to evaluate the effectiveness of steam cleaning in reducing the number of ESKAPE organisms on environmental surfaces from the stables of an equine veterinary referral hospital. Methods: Environmental sampling was performed at two timepoints (pre- and post-steam cleaning) on smooth metallic doors and rough rubber stable walls. Microbiological culture targeted ESKAPE organisms and Escherichia co...
Collins E, Barr E, Zhang C, Steadman M, Gilger B, Henriksen ML.To describe the most efficient topical horizontally centrifuged platelet-rich fibrin (H-PRF) treatment protocol for equine ulcerative keratitis (EUK) that is easy to use, and to report the preliminary concentration of growth factors and cytokines in equine H-PRF. Unassigned: 5 client-owned horses diagnosed with EUK were enrolled over an 11-month period. Unassigned: 3 horses were geldings, and 2 were mares. The mean (± SD) age was 5.95 ± 5.01 years. The owners' main goal was to avoid surgery for EUK. Unassigned: H-PRF was used in 3 different protocols: solid H-PRF, sutured to the EUK area (n ...
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...
Martano M, Montagnaro S, Power K, Cuccaro B, Cutarelli A, Maiolino P, Restucci B.This study investigated the presence of δ bovine papillomaviruses (BPV-1, BPV-2, BPV-13, BPV-14) in equine skin lesions from Southern Italy, focusing on equine sarcoids and their histopathological correlations. 63 equine skin samples were analysed using PCR and sequencing for BPV detection, and their histopathological features were assessed. BPV DNA was detected in 69.84% of the samples, with BPV-1 and BPV-2 being the most prevalent genotype, followed by BPV-13, while BPV-14 was not detected. BPV DNA was also found in non-sarcoid tumours and non-neoplastic conditions. Histopathological analys...
Musoles-Cuenca B, Padilla-Blanco M, Vitale V, Lorenzo-Bermejo T, de la Cuesta-Torrado M, Ballester B, Maiques E, Rubio-Guerri C, Velloso Alvarez A.Equine Herpesvirus Type 1 (EHV-1) is a significant pathogen within the subfamily, causing respiratory disease, abortions, and, in severe cases, equine herpesvirus myeloencephalopathy (EHM). While nasal swabs and blood samples are commonly used for real-time polymerase chain reaction (RT-PCR) diagnosis, variability in viral shedding necessitates exploring additional sample types. This study reports the first molecular detection of EHV-1 in ocular swabs from naturally infected horses during an outbreak in the Valencian Community in 2023. Nasal and ocular swabs were collected from ten symptomati...
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 ...
Slavik K, Whitlock R, Johnson A.Botulism is a severe and often fatal disease in equine patients worldwide. Clostridium botulinum is a ubiquitous soil organism which produces a potent neurotoxin resulting in neuromuscular blockade and flaccid paralysis in affected animals. Definitive diagnosis is often impractical or impossible, leading to diagnosis and treatment based on clinical experience and presenting signs. Delay in case identification and treatment results in rapid deterioration of the patient. Treatment of recumbent equine botulism cases presents challenges due to patient size and requires intensive nursing care. This...
Kholik K, Sukri A, Priscilia Riwu KH, Ayu IW, Dewi IN.The transmission of () containing virulent genes from animals to humans and the environment poses significant public health challenges. This study aimed to detect the virulence factor of the () in isolated from the feces of apparently healthy horses in the island of Sumbawa, Indonesia. The study utilized 52 fecal samples from a total horse population of 283, calculated using the disease detection formula. Fresh feces were collected immediately after excretion and placed in buffered peptone water for subsequent analysis. The samples were then isolated on eosin methylene blue media and identi...
Legere RM, Ott JA, Poveda C, Vanover D, Borba KER, Yeon Joo J, Martin CL, da Silveira BP, Bray JM, Landrock K, Wright GA, Blazier JC, Hillhouse AE....Inhalation of Rhodococcus equi causes severe pneumonia in humans and animals worldwide, most commonly affecting horse foals. The standard for preventing R. equi pneumonia in foals is transfusion of hyperimmune plasma, which is expensive and carries the risk of adverse effects. Our goal was to passively immunize foals against R. equi by nebulizing mRNA encoding an equine monoclonal antibody (mAb) against the virulence-associated protein A (VapA) directly into the lungs. VapA-specific memory B cells from an immunized horse were used to identify and select the sequence for an equine immunoglobuli...
Moreno C, Rice H.Diagnostic and treatment strategies for infectious equine tendon and ligament disorders are continually evolving where recent progress is focused on advanced imaging and evidence supporting endoscopic lavage and regional antimicrobial therapy.
Gomes-Gonçalves S, Mesquita JR, Ruano ZM, Barradas PF.Coxiella burnetii is a bacterium that causes coxiellosis in animals and Q fever in humans. While ruminants are the main reservoirs, the role of ticks in their transmission is still uncertain. This study looked for C. burnetii in ticks collected from two autochthonous breeds in Portugal: Churra Galega Mirandesa sheep and Garrano horses. A total of 555 ticks were tested, including 100 Rhipicephalus sanguineus sensu (s.) stricto (s.) from sheep and 455 Rhipicephalus bursa from horses. Coxiella burnetii was found in 7 % of R. sanguineus s.s., but not in R. bursa. Phylogenetic analysis confirmed th...
Crabtree NE, Capper AM, McKinnon LH, Epstein KL.The objective was to compare perioperative factors that may influence clinician decisions regarding antimicrobial therapy duration and outcomes in horses undergoing exploratory celiotomy. Unassigned: Horses > 1 mo of age undergoing exploratory celiotomy for colic that survived without repeat celiotomy for ≥ 5 d. Unassigned: Retrospective cohort study. Cases were grouped by duration of antimicrobial therapy: G1, ≤ 24 h; G2, 1 to 3 d; G3, > 3 d. Admission, surgical, and postoperative data from the medical records and long-term outcome assessed telephone follow-up were compared among g...
Tarillion M, Hertzsch R, Richter A.Since 28.01.2022, veterinary medicinal products must be used in accordance with the conditions of authorization (Regulation (EU) 2019/6, Article 106). This entails further restrictions on therapeutic freedom, e. g., with regard to dose deviations. To date, there is no data available in equine medicine on the scope of off-label use as any use deviating from the expert information for antibiotics, on the basis of which the feasibility of implementing the new regulations in Germany can be assessed.To collect data on the off-label use of antibiotics, a Germany-wide anonymous online survey was th...
Bannai H, Kambayashi Y, Kume K, Takebe N, Endo Y, Kawanishi N, Nemoto M, Tsujimura K.The endemic situation of respiratory disease caused by equine herpesvirus type-1 (EHV-1) and type-4 (EHV-4) was investigated in a training facility for Thoroughbred yearlings in Japan. Vaccination typically starts in mid-September or early October-only after all yearlings have arrived-leaving those introduced earlier unprotected. To bridge this immunity gap, a revised vaccination program that started earlier was implemented. In 2021-2022 and 2022-2023, yearlings were allocated to three groups according to their introduction dates. Each group received a live EHV-1 vaccine (Equi N Tect ERP, Niss...
Huang X, Deng R, Huang H, Xie H, Chen A.This case report detailed a rare co-infection of and in a 9-year-old warmblood mare, leading to severe cellulitis and secondary lymphangitis following traditional hoof blood-letting therapy. The mare exhibited acute limb swelling, fever, cutaneous ulceration, lymphatic dysfunction and unknown anemia. Comprehensive diagnostics, including bacterial culture, whole-genome sequencing, anti-elastin antibody (AEAb) ELISA, and diagnostic imaging, confirmed the pathogens causing cellulitis and secondary lymphangitis. AEAb levels were elevated, correlating with lymphatic degradation, while radiography...
Schlote MT, Drozdzewska K, Ehrle A, Lischer C, Gehlen H.This case report describes the use of computed tomography for the diagnosis and surgical planning in a horse with bilateral nephrolithiasis. An adult Warmblood stallion (460 kg) was presented with chronic weight loss, hypercalcemia and azotemia. Ultrasonographic examination identified hyperechoic masses in both kidneys and dilation of the right renal pelvis. A solid mass was evident upon transrectal examination on the left side. Computed tomography (CT) of the caudal abdomen was performed and provided good quality images that facilitated exact determination of the size, position and extent of ...
van Maanen K, van den Wollenberg L, de Haan T, Frippiat T.Monitoring infectious diseases is essential for safeguarding equine health and ensuring the sustainability of the horse industry. In 2019, the Royal Veterinary Association of the Netherlands (KNMvD) and Royal GD (GD Animal Health) launched SEIN (Surveillance of Equine Infectious diseases in the Netherlands), a voluntary surveillance system for laboratory-confirmed outbreaks of equid alphaherpesvirus 1 (EHV-1), equid alphaherpesvirus 4 (EHV-4), equine influenza virus (EIV), and subsp. . This retrospective study analyzed 364 confirmed outbreaks reported through SEIN between June 2019 and April ...
Suvanto MT, Truong Nguyen PT, Vauhkonen H, Olander V, Joensuu R, Culverwell CL, Kaansalo K, Hepojoki J, Vapalahti O, Korhonen EM, Smura T, Huhtamo E.The genus (, ) comprises several globally important vector-borne animal viruses, such as borne bluetongue virus, African horse sickness virus and epizootic haemorrhagic disease virus (EHDV). Orbiviruses that are associated with mosquitoes are a diverse group including established mosquito-borne animal pathogens such as the Peruvian horse sickness virus and phylogenetically related less well-characterized viruses isolated mostly from mammals. Although reported from various geographic regions, these viruses have not previously been detected in northern Europe. Using next-generation sequencing a...
Gamage C, Holl W, Parreño V, Thieulent CJ, Balasuriya UBR, Vissani MA, Barrandeguy ME, Carossino M.Group A rotavirus (RVA) infections are a leading cause of neonatal diarrhoea in foals. Neonatal mice could serve as a useful tool to study the pathogenesis of equine RVA (ERVA) as well as a preclinical model for assessment of vaccine efficacy. This study aimed to comparatively evaluate the clinical, virological and pathological features of ERVA G3P[12] and G14P[12] infection in neonatal mice and compare them with porcine OSU G5P[7] and bovine UK G6P[5] RVA reference strains. Neonatal mice orally inoculated with equine, bovine and porcine RVA developed short-lived diarrhoea at variable rates, G...
Leus EK, Collins N, Gruyaert M, Kennedy RN, McConnell E, McGorum BC, Luethy D, Sanz M, Versporten A, Viljoen A, Lyle CH.Antimicrobial resistance (AMR) is increasingly recognised in equine medicine. Antimicrobial use (AMU) is a key driver of AMR. Objective: To pilot a point prevalence survey (PPS), based on the Global-PPS used in human hospitals, to obtain data on antibiotic prescribing and AMR in equine hospitals and to identify targets for improvement in AMU. Methods: Point prevalence survey. Methods: Eight equine hospitals located in Australia, Belgium, South Africa, the United Kingdom and the United States were recruited. Data on AMU were collected from all in-patients on antibiotic treatment at 08h00 on fou...
Yuan Y, Hao Y, Peng C, Zhang D, Ma W, Xiao P, Li N.Getah virus (GETV) is a member of the of the . It is a single-stranded positive-RNA virus that is mainly transmitted by mosquitoes. In recent years, the spread of GETV has become increasingly serious, causing serious losses to the animal economy and posing a potential threat to public health. GETV infected animals extend from traditional domestic animals such as horses and pigs to cattle, foxes and other animals. Especially in China, the virus has been detected in many provinces in recent years. In addition, GETV-specific antibodies were detected in healthy humans. However, the threat posed b...
Nikvand AA, Jalali SM, Bahrami S, Rahij Torfi H.Trypanosoma evansi (T. evansi) is a hemoprotozoan parasite affecting camels and equids, such as horses, mules, and donkeys, and is known to cause surra disease in these animals. Despite the worldwide distribution of T. evansi infections in equids, surra has not been reported in Arabian horses in Khuzestan Province for over 60 years. In September 2018, a 7-year-old Arabian mare was referred from a 10-horse farm in the suburbs of Ahvaz City. The mare presented with a history of weight loss, poor appetite, and proximity to a camel herd. Physical examination revealed a poor body condition score ...
Turcotte GK, O'Sullivan TL, Spence KL, Winder CB, Greer AL.Horses may travel for a variety of reasons, leading to potential exposure to pathogens. Typically, these movements are bidirectional with horses returning to their home facility, therefore also risking pathogen exposure to resident horses at home facilities. The Canadian National Farm and Facility Level Biosecurity Standard for the Equine Sector was designed to outline best practices for managing biosecurity at equestrian facilities, however, there is a gap between the implementation of these recommendations and the day-to-day operations of equestrian facilities. This study aimed to explore th...
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...
Kutumbetov L, Myrzakhmetova B, Tussipova A, Zhapparova G, Tlenchiyeva T, Bissenbayeva K, Nurabayev S, Kerimbayev A.Equine rhinopneumonia, caused by equine herpesvirus types 1 and 4 (EHV-1 and EHV-4), continues to be a significant health and economic concern in the global equine industry, particularly in Kazakhstan. While vaccines targeting EHV-1 are available, there is currently no licensed monovalent vaccine for EHV-4, and existing formulations offer limited protection against this serotype. This study aimed to develop and evaluate a freeze-dried, live-attenuated EHV-4 vaccine with improved safety, stability, and immunogenicity. Methods: A field isolate of EHV-4 was attenuated through serial passaging in ...
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...
Granella MCS, Mendes RP, da Silva Casa M, Ribeiro GSN, Sangioni LA, Vogel FSF, Braünig P, Ferian PE, Salbego FZ, Schwarz DGG, Fonteque JH.Protozoan Neospora spp. is known to negatively affect horses reared in rural and urban environments, being studied for causing abortion, neonatal mortality and central nervous system disorders in horses. This study aimed to verify the occurrence of anti-Neospora spp. antibodies in horses bred in rural and urban areas from southern Brazil and the risk factors associated with infection. The study consisted of 400 horses, which 241 were bred in rural areas and 159 in urban areas. The detection of serum anti-Neospora spp. antibodies was determined using Immunofluorescence Antibody Test (IFAT). The...
Jacobsen S, Niewold TA, Halling-Thomsen M, Nanni S, Olsen E, Lindegaard C, Andersen PH.The aim of the study was to determine the intraarticular serum amyloid A (SAA) response pattern in horses with inflammatory arthritis. Inflammatory arthritis was induced by injection of lipopolysaccharide (LPS) into the radiocarpal joint of four horses. Serum and synovial fluid (SF) samples were collected before and at 4, 8, 12, 24, 48, 72, 96, and 144 h after injection. Concentrations of SAA were measured by immunoturbidometry, and expression of SAA isoforms was visualized by denaturing isoelectric focusing and Western blotting. The LPS injection caused systemic and local clinical signs of in...
Nielsen MK, Kaplan RM, Thamsborg SM, Monrad J, Olsen SN.Development of resistance to anthelmintic drugs by horse strongyles constitutes a growing threat to equine health because it is unknown when new drug classes can be expected on the market. Consequently, parasite control strategies should attempt to maintain drug efficacy for as long as possible. The proportion of a parasite population that is not exposed to anthelmintic treatment is described as being "in refugia" and although many factors affect the rate at which resistance develops, levels of refugia are considered the most important as these parasites are not selected by treatment and so pr...
Reed SM, Toribio RE.Equine herpesvirus infections in horses remain a significant cause of abortion and neurologic disease. These viruses are also responsible for mild signs of respiratory disease. The ability to establish latent infections with periodic reactivation or transmission to other horses is an important feature of these herpesviruses. One of the most unique aspects of this report is the description of horses demonstrating neurologic signs serving as the source of infection for other horses. Accurate diagnosis and better means of protection for horses remain problems facing veterinarians and horse owners...
Amtmann E, Müller H, Sauer G.Bovine papilloma virus (BPV) appears to be the etiological agent of common equine connective tissue tumors. We investigated the physical state of the viral DNA within such tumors and found no indication for integration into the host genome. The BPV genomes were present as free circular episomes. Two equine sarcoids were shown to contain multiple copies of free circular BPV type 1 (BPV-1) DNA. When the tumors were digested with several single-cut restriction enzymes, there were only form III BPV-1 DNA sequences could be revealed. One of the sarcoids contained, apart from wild-type BPV-1 DNA, a ...
Knowles DP, Kappmeyer LS, Stiller D, Hennager SG, Perryman LE.Horses infected with Babesia equi were previously identified by the presence of antibodies reactive with a merozoite surface protein epitope (D. P. Knowles, Jr., L. E. Perryman, L. S. Kappmeyer, and S. G. Hennager. J. Clin. Microbiol. 29:2056-2058, 1991). The antibodies were detected in a competitive inhibition enzyme-linked immunosorbent assay (CI ELISA) by using monoclonal antibody 36/133.97, which defines a protein epitope on the merozoite surface. The gene encoding this B. equi merozoite epitope was cloned and expressed in Escherichia coli. The recombinant merozoite protein, designated equ...
Benavides JA, Salgado-Caxito M, Opazo-Capurro A, González Muñoz P, Piñeiro A, Otto Medina M, Rivas L, Munita J, Millán J.Antibiotic-resistant bacteria of critical importance for global health such as extended-spectrum beta-lactamases-producing (ESBL)- have been detected in livestock, dogs, and wildlife worldwide. However, the dynamics of ESBL- between these animals remains poorly understood, particularly in small-scale farms of low and middle-income countries where contact between species can be frequent. We compared the prevalence of fecal carriage of ESBL- among 332 livestock (207 cows, 15 pigs, 60 horses, 40 sheep, 6 goats, 4 chickens), 82 dogs, and wildlife including 131 European rabbits, 30 rodents, and 12 ...
Rushton JO, Lecollinet S, Hubálek Z, Svobodová P, Lussy H, Nowotny N.An unexpectedly high infection rate (26.1%) of tick-borne encephalitis virus (TBEV) was identified in a herd of 257 horses of the same breed distributed among 3 federal states in Austria. Young age (p<0.001) and male sex (p=0.001) were positively associated with infection.
Harrold SM, Cook SJ, Cook RF, Rushlow KE, Issel CJ, Montelaro RC.Equine infectious anemia virus (EIAV) infection of horses is characterized by recurring cycles of disease and viremia that typically progress to an inapparent infection in which clinical symptoms are absent as host immune responses maintain control of virus replication indefinitely. The dynamics of EIAV viremia and its association with disease cycles have been well characterized, but there has been to date no comprehensive quantitative analyses of the specific tissue sites of EIAV infection and replication in experimentally infected equids during acute disease episodes and during asymptomatic ...
Roy MF, Kwong GP, Lambert J, Massie S, Lockhart S.Despite its widespread use in equine medicine, the clinical value of the systemic inflammatory response syndrome (SIRS) concept in horses remains unknown. Objective: To study the prognostic value of measures of SIRS in horses and identify the best model of severe SIRS to predict outcome. Methods: A total of 479 consecutive adult horse emergency admissions to a private primary referral practice. Methods: Prospective observational study. All adult horses admitted for emergency treatment over the study period were included. Multivariate logistic regression and stepwise model selection were used. ...
Kono Y, Hirasawa K, Fukunaga Y, Taniguchi T.Horses which had passed a few months to a few years asymptomatically after the last recurrence of equine infectious anemia (EIA) showed a typical febrile response after treatment with the immunosuppressive agent, dexamethasone (DM) or cyclophosphamide (CY). In horses showing a febrile response, EIA virus which had not been neutralized by neutralizing antibody previously produced was propagated. In DM-treated horses it disappeared from the blood soon after pyretolysis and antibody against the virus was produced promptly. In contrast, detectable viremia persisted in CY-treated horses for 10 to 8...
Smit H, Gaastra W, Kamerling JP, Vliegenthart JF, de Graaf FK.The erythrocyte receptor for Escherichia coli K99 fimbrial adhesin was isolated from equine erythrocytes and characterized as Neu5Gc-alpha(2----3)-Galp-beta(1----4)-GLcp-beta(1----1)-Ceramide. This glycolipid acted as the receptor for K99 by four different experimental approaches: inhibition of equine erythrocyte hemagglutination by preincubation of K99-positive bacteria or purified K99 fimbriae with the isolated glycolipid; inhibition of attachment of K99-positive bacteria to porcine intestinal epithelial cells in the presence of the isolated glycolipid; induction of binding of K99-positive b...
Walter S, Rasche A, Moreira-Soto A, Pfaender S, Bletsa M, Corman VM, Aguilar-Setien A, García-Lacy F, Hans A, Todt D, Schuler G....The hepatitis C virus (HCV) is a major human pathogen. Genetically related viruses in animals suggest a zoonotic origin of HCV. The closest relative of HCV is found in horses (termed equine hepacivirus [EqHV]). However, low EqHV genetic diversity implies relatively recent acquisition of EqHV by horses, making a derivation of HCV from EqHV unlikely. To unravel the EqHV evolutionary history within equid sister species, we analyzed 829 donkeys and 53 mules sampled in nine European, Asian, African, and American countries by molecular and serologic tools for EqHV infection. Antibodies were found in...
Poissant J, Gavriliuc S, Bellaw J, Redman EM, Avramenko RW, Robinson D, Workentine ML, Shury TK, Jenkins EJ, McLoughlin PD, Nielsen MK, Gilleard JS.Horses are ubiquitously infected by a diversity of gastro-intestinal parasitic helminths. Of particular importance are nematodes of the family Strongylidae, which can significantly impact horse health and performance. However, knowledge about equine strongyles remains limited due to our inability to identify most species non-invasively using traditional morphological techniques. We developed a new internal transcribed spacer 2 (ITS2) DNA metabarcoding 'nemabiome' assay to characterise mixed strongyle infections in horses and assessed its performance by applying it to pools of infective larvae ...
von Samson-Himmelstjerna G.During the past two decades anthelmintic resistance in equine parasites has been found in the group of small strongyle species (cyathostomins) and in the ascarid species Parascaris equorum. The ubiquitous nature and possible severe consequences of disease with these nematodes make them the prime targets of current worm control programmes. Traditional control strategies mainly rely on the strategic application of anthelmintics, currently represented by three major drug classes: benzimidazoles (BZ), the tetrahydropyrimidine pyrantel (PYR) and macrocyclic lactones (ML). Following decades of routi...
Moodley A, Stegger M, Bagcigil AF, Baptiste KE, Loeffler A, Lloyd DH, Williams NJ, Leonard N, Abbott Y, Skov R, Guardabassi L.Region X of the protein A gene (spa) was sequenced from methicillin-resistant Staphylococcus aureus (MRSA) isolates originating from animals, humans and the environment at veterinary hospitals in the UK and Ireland. MRSA transmission between animals and veterinary staff was assessed on the basis of spa typing, PFGE and epidemiological data. Methods: MRSA isolates from dogs (n = 27), horses (n = 9), cats (n = 6), staff (n = 22) and environmental surfaces (n = 3) were analysed by PFGE and spa typing. Known contacts between human and animal MRSA carriers were ascertained from the veterinary hospi...
Rikihisa Y, Perry BD, Cordes DO.Potomac horse fever is characterized by fever, anorexia, leukopenia, profuse watery diarrhea, dehydration, and high mortality. An ultrastructural investigation was made to search for any unusual microorganisms in the digestive system, lymphatic organs, and blood cells of ponies that had developed clinical signs after transfusion with whole blood from horses naturally infected with Potomac horse fever. A consistent finding was the presence of rickettsial organisms in the wall of the intestinal tract of these ponies. The organisms were found mostly in the wall of the large colon, but fewer organ...
Tanaka T, Kasai H, Yamashita A, Okuyama-Dobashi K, Yasumoto J, Maekawa S, Enomoto N, Okamoto T, Matsuura Y, Morimatsu M, Manabe N, Ochiai K....Equine hepacivirus (EHcV) has been identified as a closely related homologue of hepatitis C virus (HCV) in the United States, the United Kingdom, and Germany, but not in Asian countries. In this study, we genetically and serologically screened 31 serum samples obtained from Japanese-born domestic horses for EHcV infection and subsequently identified 11 PCR-positive and 7 seropositive serum samples. We determined the full sequence of the EHcV genome, including the 3' untranslated region (UTR), which had previously not been completely revealed. The polyprotein of a Japanese EHcV strain showed ap...
Ledizet M, Kar K, Foellmer HG, Wang T, Bushmich SL, Anderson JF, Fikrig E, Koski RA.West Nile (WN) virus is a flavivirus that first appeared in North America in 1999. Since then, more than 600 human deaths and 22,000 equine infections have been attributed to the virus in the United States. We expressed a truncated form of WN virus envelope (E) protein in Drosophila S2 cells. This soluble recombinant E protein was recognized by antibodies from naturally infected horses, indicating that it contains native epitopes. Mice and horses produced high-titer antibodies when immunized with recombinant E protein combined with aluminum hydroxide. Immunized mice were resistant to challenge...
Bogerd HP, Tallmadge RL, Oaks JL, Carpenter S, Cullen BR.Equine infectious anemia virus (EIAV), uniquely among lentiviruses, does not encode a vif gene product. Other lentiviruses, including human immunodeficiency virus type 1 (HIV-1), use Vif to neutralize members of the APOBEC3 (A3) family of intrinsic immunity factors that would otherwise inhibit viral infectivity. This suggests either that equine cells infected by EIAV in vivo do not express active A3 proteins or that EIAV has developed a novel mechanism to avoid inhibition by equine A3 (eA3). Here, we demonstrate that horses encode six distinct A3 proteins, four of which contain a single copy o...
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...
Di Gennaro A, Lorusso A, Casaccia C, Conte A, Monaco F, Savini G.A serum neutralization assay (SN) was compared with the official plaque reduction neutralization test for the quantitation of West Nile virus antibodies. A total of 1,348 samples from equid sera and 38 from human sera were tested by these two methods. Statistically significant differences were not observed, thus supporting the use of SN for routine purposes.
Ueti MW, Palmer GH, Kappmeyer LS, Statdfield M, Scoles GA, Knowles DP.The protozoan parasite Babesia equi replicates within erythrocytes. During the acute phase of infection, B. equi can reach high levels of parasitemia, resulting in a hemolytic crisis. Horses that recover from the acute phase of the disease remain chronically infected. Subsequent transmission is dependent upon the ability of vector ticks to acquire B. equi and, following development and replication, establishment of B. equi in the salivary glands. Although restriction of the movement of chronically infected horses with B. equi is based on the presumption that ticks can acquire and transmit the ...
Sieber S, Gerber V, Jandova V, Rossano A, Evison JM, Perreten V.A total of 70 Staphylococcus aureus isolates from postoperative infections in hospitalized horses were isolated between January 2005 and January 2011. Among them, 12 isolates were methicillin-susceptible S. aureus (MSSA), 18 were borderline-oxacillin-resistant S. aureus (BORSA), and 40 were methicillin-resistant S. aureus (MRSA). During the same period, the equine clinic personnel were screened for nasal carriage of BORSA and MRSA. Genotyping revealed that BORSA ST1(MLST)-t2863(spa) isolates were responsible for most equine infections and were the main isolates found in colonized members of th...
Kennedy R, Lappin DF, Dixon PM, Buijs MJ, Zaura E, Crielaard W, O'Donnell L, Bennett D, Brandt BW, Riggio MP.Equine periodontal disease is a common and painful condition and its severe form, periodontitis, can lead to tooth loss. Its aetiopathogenesis remains poorly understood despite recent increased awareness of this disorder amongst the veterinary profession. Bacteria have been found to be causative agents of the disease in other species, but current understanding of their role in equine periodontitis is extremely limited. The aim of this study was to use high-throughput sequencing to identify the microbiome associated with equine periodontitis and oral health. Subgingival plaque samples from 24 h...
Kydd JH, Smith KC, Hannant D, Livesay GJ, Mumford JA.Twelve adult ponies and 2 conventional foals were exposed intranasally to EHV-1, strain Ab4 (TCID50 10(-6.6) and samples of respiratory tract associated lymphoid tissues were recovered between 12 h and 13 days after infection. Infectious virus was detected in tissue homogenates using susceptible cell monolayers and expression of viral antigens was monitored using indirect immunoperoxidase histochemistry on paraffin sections. The results showed both infectious EHV-1 and viral antigens in respiratory tract associated lymph nodes 12 h after exposure. Infected leucocytes were identified morphologi...
Lu G, Ou J, Ji J, Ren Z, Hu X, Wang C, Li S.Getah virus (GETV) is a mosquito-borne virus that was first determined in Malaysia in 1955, and can infect humans and multiple other mammals. GETV infection in horses has been reported in Japan and India, and causes great economic losses. In China, GETV has been identified in mosquitoes, pigs, foxes, and cattle with a wide geographical distribution, but has not been detected in horses. In August 2018, a sudden onset of fever was observed in racehorse in an equestrian training center in Guangdong Province in southern China. Blood samples were collected from the sick horse, and PCR/RT-PCR analys...
Diab SS, Songer G, Uzal FA.Clostridium difficile is considered one of the most important causes of diarrhea and enterocolitis in horses. Foals and adult horses are equally susceptible to the infection. The highly resistant spore of C. difficile is the infectious unit of transmission, which occurs primarily via the fecal-oral route, with sources of infection including equine feces, contaminated soil, animal hospitals, and feces of other animals. Two major risk factors for the development of C. difficile associated disease (CDAD) in adult horses are hospitalization and antimicrobial treatment, although sporadically, cases...
Ross PF, Rice LG, Osweiler GD, Nelson PE, Richard JL, Wilson TM.During the 1989 corn harvest season, numerous reports of equine leukoencephalomalacia (ELEM) outbreaks and a pulmonary edema (PPE) syndrome in swine from several regions of the United States were received by the National Veterinary Services Laboratories (NVSL), Ames, Iowa. Previous and concurrent research linked Fusarium moniliforme and fumonisin-contaminated feeds to both diseases. Chemical and mycological investigations revealed fumonisin B1 (FB1) concentrations of 20 to 360 ppm in suspect swine feeds and 8 to 117 ppm in suspect equine feeds. Nonproblem feeds contained concentrations below 8...
