Disease transmission in horses refers to the spread of infectious agents such as bacteria, viruses, fungi, and parasites among equine populations. These pathogens can be transmitted through various routes, including direct contact, vector-borne transmission, or environmental exposure. Factors influencing disease transmission include horse density, management practices, and biosecurity measures. Understanding the mechanisms and conditions that facilitate the spread of diseases is essential for developing effective prevention and control strategies. This page compiles peer-reviewed research studies and scholarly articles that investigate the modes of transmission, risk factors, and management practices related to infectious diseases in horses.
Kasel JA, Couch RB.The recognition of an antigenic relationship between the haemagglutinins of A/Equi-2 and A2/Hong Kong/68 viruses led to experimental studies in man and horses with these virus types.Human volunteers were inoculated with A/Equi-2/Miami/63 virus and virus shedding ensued in all subjects. The most common clinical response was a febrile illness indistinguishable from naturally occurring human influenza. After administration of A2/Hong Kong/68 virus to 10 ponies there was virus shedding from 9 and a febrile response in 6.When the human subjects previously inoculated with equine virus were challenge...
Lee CL, Zandrew F, Davidsohn I.One hundred infectious mononucleosis and the same number of non-infectious mononucleosis sera were studied to evaluate the sensitivity and specificity of horse erythrocytes in the diagnosis of infectious mononucleosis. Titres of horse agglutinins in infectious mononucleosis sera ranged from 28 to 7,168 with a geometric mean of 550, whereas the corresponding sheep agglutinin titres ranged from less than 7 to 3,584, with a geometric mean of 126. Horse agglutinin titres of non-infectious mononucleosis sera ranged from less than 7 to 896, with a geometric mean of 59. Infectious mononucleosis sera ...
Becker W.From 1981 until 1987 we investigated the more detailed circumstances regarding a prophylactic vaccination in altogether 37 stud farms with a history of virus abortion. In 23 cases, in which Prevaccinol and/or Resequin were used, it was found that the following of vaccination schedule and necessary immunization programmes respectively, had considerable imperfections. In seven cases prophylactic vaccinations were not carried out or corresponding questionnaires were not answered. The fact that in the present data no case of virus abortion was observed, when the mare was vaccinated according to th...
Tåmová B, Stumpa A, Zakopal J, Vĕzníková D, Mensík J.Equine influenza occurred in Czechoslovakia 14 years after the last epizootic in horses that had returned from abroad. Six strains A (Heq1Neq1) antigenically related to, but not identical with, strain A/eq/Praha/56 were isolated from 10 washings. Seroconversion was demonstrated with paired sera, but the antibody increase was more marked against the newly isolated strain.
Anandu S, Tanuj GN, Vijayasarathi MK, Manjusha KM, Samanta S, Bandyopadhyay S, Sankar M.Ocular setariasis is an ectopic infection caused by a parasite under the genus Setaria. Adult worms belong to the Setariidae family and typically reside in the peritoneal cavity of ungulates. However, immature forms of these species may aberrantly migrate to the eyes of cattle, buffalo, goats, horses and several other hosts, leading to corneal opacity and blindness. Here, we have distinguished the Setaria digitata collected from both equine and buffalo hosts based on the morphology, molecular profiling of mitochondrial cytochrome c oxidase subunit 1 (Cox1), cytochrome c oxidase subunit 3 (Cox3...
Maeda M, Abe M, Aoshima K, Kobayashi A, Fukushi H, Kimura T.Equine herpesvirus-1 (EHV-1) causes respiratory diseases, abortion, and encephalomyelitis in horses. The EHV-1 immediate-early (IE) protein, essential for viral replication, is transactivated by the binding of a multiprotein complex including the open reading frame 12 (ORF12) and some host factors to the IE promoter region. Promoter-associated non-coding RNAs (pancRNAs), which are transcribed from bidirectional promoters, regulate the transcription of neighboring genes in mammals and pathogens. In this study, we identified a novel pancRNA transcribed from across the areas of the 5'-untranslate...
Kannekens-Jager MM, Duim B, der Graaf-van Bloois LV, Zomer AL, Broekhuizen-Stins MJ, Boswinkel M, Wagenaar JA, Broens EM.In 2020 and 2022, nine cases of surgical site infections with a methicillin-resistant Staphylococcus aureus (MRSA) were diagnosed in horses in an equine referral clinic. Sixteen isolates (horses, n=9; environment, n=3; and staff members, n=4) were analysed retrospectively using Nanopore whole-genome sequencing to investigate the relatedness of two suspected MRSA outbreaks (2020 and 2022). The MRSA isolates belonged to ST398 and ST612. ST398 genomes from 2020 and 2022 formed three phylogenetic clusters. The first ST398 cluster from 2020 consisted of isolates from five horses and one staff membe...
Papouskova A, Drabkova Z, Brajerova M, Krutova M, Cizek A, Tkadlec J.We performed a retrospective analysis of MRSA isolates collected at the university equine clinic including clinical isolates from 2008 to 2021 and screening environmental, equine and personnel isolates from 2016. Screening and clinical samples were cultured on Brilliance MRSA 2 and Columbia agar (Oxoid), respectively, with enrichment for environmental samples. Antimicrobial susceptibility was assessed by disc diffusion. All the isolates were characterized by spa typing. Eighteen selected isolates were subjected to WGS with subsequent wgMLST clonal analysis. Among 75 MRSA isolates, five spa typ...
Forman R, Lalzar M, Inbar M, Berman TS.Reintroduced animals face disease risks, potentially impacting both the reintroduced and the local wildlife/domestic populations. This study focuses on the Asiatic wild asses () reintroduced to the Negev desert in southern Israel. Despite potential threats of disease spill-over to and from domesticated donkeys and horses in the area, there are no records of the gastrointestinal nematodes (GIN) of the wild ass population. We used DNA metabarcoding on fecal samples of wild asses collected across seasons and habitats, near water sources that they frequently use. Ten GIN species were detected in t...
Cornell TR, Fye BL, Nyassi E, Ceesay F, Jallow M, Langendonk RF, Wootton DG, Pinchbeck G, Scantlebury CE.Exposure rates to species, the causative agent of equine epizootic lymphangitis (EL), are unknown amongst working equids in The Gambia. The primary aims of this study were to estimate anti- antibody seroprevalence in the equid population in rural The Gambia and to explore risk factors for seropositivity. Unassigned: A nationwide cross-sectional study was conducted (February-July 2022), representing baseline measurements of a longitudinal cohort study. Horses ( 463) and donkeys ( = 92) without EL signs were recruited in 18 study sites. Following informed owner consent, equid clinical and m...
Dubey JP, Gupta A, Calero-Bernal R, de Araujo LS, García-Gil ML, Battle J, Ankarah A, Van Why K, Brown JD, Rosenthal BM.The protozoan Sarcocystis neurona can cause severe disease in horses, marine mammals, and several other animal species in North America. The Virginia opossum (Didelphis virginiana) is its definitive host, and the raccoon (Procyon lotor) has been considered its primary intermediate host in the USA. Although canids have not previously been identified as important intermediate hosts for this parasite, we here report several natural cases in the gray fox (Urocyon cinereoargenteus). We identified muscular infections in 11 (23.9 %) of 46 gray foxes from Pennsylvania, USA. In hematoxylin and eosin ...
Villa RE, Azimonti G, Bonos E, Christensen H, Durjava M, Dusemund B, Gehring R, Glandorf B, Kouba M, López-Alonso M, Marcon F, Nebbia C, Pechová A....Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of a preparation of CNCM I-1077 as a zootechnical feed additive for several animal species. The additive, existing in a not-coated and a coated form, is currently authorised for use in feed for calves, cattle for fattening, dairy cows, dairy goats and dairy sheep, lambs, all minor ruminant species for fattening and rearing, horses and camelids for fattening and rearing. This application regards the request for the extension of use in all ruminants and camelids reared for...
Alayil AL, Horwood PF, Gummow B, Picard JA, Joone CJ.Leptospira species are found worldwide, favouring tropical regions, and infect a wide range of animal species. Although renal persistence in infected individuals and excretion in urine is thought to be the primary mechanism of disease transmission, recent reports have suggested that persistence in the reproductive tract may be a feature in certain species, including the horse. The aim of this study was to investigate leptospiral infection, particularly within the reproductive tract, in healthy, non-breeding mares. Serum and endometrial swab samples were collected from 50 mares from the James C...
Akbari H, Basaki M, Imani Baran A, Akbarzadeh Z.Anaplasmosis, a tick-borne disease with worldwide distribution, impacts ruminants, equines, carnivores, and humans. This study aimed to investigate Anaplasma phagocytophilum in horses from Ardabil province and Anaplasma ovis in small ruminants from East Azerbaijan province using the Nested Polymerase Chain Reaction (PCR) method. Blood samples were taken from the jugular vein of 100 healthy horses in the Ardabil province and 156 healthy sheep and goats (116 sheep and 40 goats) in the East Azerbaijan province during the spring and summer seasons of 2016 in northwest Iran. The collected blood sam...
Padalino B, Pellegrini F, Felici M, Zappaterra M, Catella C, Cordisco M, Lorusso E, Cirone F, Pratelli A.Respiratory disorders (RDs) are a common transport-related welfare consequence in horses. This prospective study described the journeys of horses transported to two slaughterhouses in Italy, documented the prevalence of potentially RD-related pathogens, and identified possible predisposing factors. Data were recorded from arrival until 48 h after arrival and included the collection of Deep Nasopharyngeal Swabs (DNS), journey details and welfare assessment of horses (n = 155). PCR was used to quantify the presence of influenza A virus, reovirus, equine herpesvirus type 1 and 4, adenovirus, r...
Smith MZ, York M, Townsend KS, Martin LM, Gull T, Coghill LM, Ericsson AC, Johnson PJ.Whereas restoration of fecal consistency after treatment with clioquinol for chronic diarrhea and free fecal water syndrome has been attributed to its antiprotozoal properties, actions of clioquinol on the colonic bacterial microbiota have not been investigated. Objective: Characterize the dynamics of fecal microbial diversity before, during, and after PO administration of clioquinol to healthy horses. Methods: Experimental prospective cohort study using a single horse group. Methods: Eight healthy adult horses received PO clioquinol (10 g, daily) for 7 days. Feces were obtained daily for ...
Albert E, Biksi I, Laczkó L, Miló L, Cseri K, Bőkényné Tóth R, Papp D, Halmay D, Bódai E, Bakos Z.Here we report the isolation of Streptococcus hillyeri from a thoracic sample from a horse. A 17-y-old Hungarian Sport Horse mare was referred to the equine clinic of the University of Veterinary Medicine Budapest, Hungary, with suspected pleuritis. Upon arrival, the horse was febrile and had tachycardia, severe inspiratory dyspnea, and tachypnea. Thoracic ultrasonography revealed severe bilateral pleural effusion, and a large area of lung consolidation. After sampling of both hemithoraces, 66 L of turbid exudate were drained. Based on these findings, a tentative diagnosis of septic pleuritis ...
Kozak S, Merda D, Chesnais V, Breuil MF, Harrison M, Zdovc I, Golob M, Petry S, Duquesne F.Taylorella equigenitalis is the causative agent of contagious equine metritis, an internationally regulated sexually-transmitted infection in horses, which is of great concern as it usually results in temporary infertility. Taylorella asinigenitalis, the second member of the genus, is mainly found in donkeys and is considered non-pathogenic, although a first natural outbreak was reported in 2019 in the United Arab Emirates. Multilocus sequence typing (MLST) is currently used to study the epidemiology of Taylorella spp. but, while highly transposable and reproducible, it only focuses on < 0.5...
Haenni M, Murri S, Drapeau A, Rafidinarivo I, Gilles S, Keck N, Léon A, Sulter A, Tricaud MC, François P, Madec JY.Staphylococcus aureus is an important zoonotic pathogen that has often been seen in animals through the prism of the MRSA clonal complex (CC) 398 in pigs and in-contact humans. The goal of this study was first to assess the prevalence of MRSA, and second to look for MSSA CC398 in cats, dogs and horses in France. Methods: Clinical S. aureus isolates (n = 479) were collected from 186 cats, 143 dogs and 150 horses during 2022-2023 all over the French territory. Antibiograms were performed on all isolates. MRSA and MSSA CC398 isolates were subject to WGS. Core genome (cg) MLST-based and SNP-ba...
Gerras J, Young K, Roberts D, Waldman G, Salmon JH, Gilger BC.To describe the ocular findings, chronology of disease, and serum leptospiral titers in a group of horses, mules, and donkeys following an outbreak of leptospirosis. Unassigned: Fifty Equidae in central North Carolina had ophthalmic examinations and serum leptospiral microscopic agglutination test (MAT) titers performed every 3-6 months for 24 months followed by a final examination at 34 months. Unassigned: Throughout the nearly three-year study period, 17 horses (34%; 17/49 horses) developed signs of uveitis; 20 eyes (20/34; 58.8%) of these 17 horses were visual at the initial examinati...
Wright CA, Lawton K, Barnum S, Craig BW, Farwell BR, Blea J, McCook C, Pusterla N.This study aimed to determine if exercise increases the frequency of selected respiratory viruses/bacteria shedding in non-clinical horses using nose wipes. Nose wipes were taken pre- and post- exercise from 133 healthy horses of various ages and disciplines. Wipes were assayed for the presence of selected common (equine herpesvirus-1 (EHV), EHV-4, S. equi spp equi) and commensal (EHV-2, EHV-5, S. equi spp zooepidemicus) respiratory pathogens. The frequency of detection increased significantly (p < 0.05) in the post-exercise wipes for EHV-1, EHV-2, EHV-5, and S. zooepidemicus. EHV-4 and S. equ...
O'Kennedy MM, Reedy SE, Abolnik C, Khan A, Smith T, du Preez I, Olajide E, Daly J, Cullinane A, Chambers TM.Equine influenza (EI) is a highly contagious acute respiratory disease of wild and domesticated horses, donkeys, mules, and other Equidae. EI is caused by the Equine Influenza virus (EIV), is endemic in many countries and outbreaks still have a severe impact on the equine industry globally. Conventional EI vaccines are widely used, but a need exists for a platform that facilitates prompt manufacturing of a highly immunogenic, antigenically matched, updated vaccine product. Here we developed a plant-produced bivalent EI virus-like particle (VLP) vaccine candidate which lacks the viral genome an...
Shnaiderman-Torban A, Meltzer L, Zilberman-Daniels T, Navon-Venezia S, Cohen A, Sutton GA, Blum SE, Amit S, Steinman A.Infections with extended-spectrum beta-lactamase-producing Enterobacterales (ESBL-PE) contribute to morbidity and mortality in human neonates. In foals, data are scarce. Objective: Determine the association between ESBL-PE gastrointestinal colonization on hospital admission and infections in hospitalized neonates. Methods: Sixty-seven foals. Methods: Prospective study of foals admitted to a veterinary hospital. Foals were screened for ESBL-PE colonization and for infections. Risk factors and clinical outcomes were analyzed. Results: Seventy-six percent of foals suffered from at least 1 bacteri...
Fernandes TA, Paulino PG, Dos Santos Juliano D, Rabello CA, de Oliveira NVB, de Souza Santana M, Peckle M, Massard CL, da Costa Angelo I, Jacob JCF....Equine piroplasmosis (EP) is a reportable disease according to the World Organization for Animal Health (WOAH), caused by Babesia caballi, Theileria equi and T. haneyi. This syndrome is prevalent in tropical and subtropical regions, including various areas in Brazilian. This study examines EP in the Distrito Federal, Brazil, focusing on prevalence, epidemiological characteristics, and circulating genotypes. Epidemiological data and whole blood samples were collected from horses in the Distrito Federal. DNA was analyzed using qPCR for Theileria sp. and B. caballi, followed by cPCR for 18S rDNA ...
Macías-Rioseco M, Ochoa J, Choi EA, Blanchard P, Moeller RB, Uzal FA. spp. can cause gastroenteritis, hepatitis, bacteremia, and abortions in domestic animals and humans. Some spp. are zoonotic. To our knowledge, hepatitis caused by has not been reported in horses. Here we present a case of acute necrosuppurative hepatitis caused by infection in a 3-y-old gelding, and we review the literature on infections in various animal species. The horse had a one-week history of weight loss and weakness before becoming recumbent and dying. Grossly, the liver had rounded edges and was mottled. There were ecchymoses on the gastric serosa, and a large amount of mucoid, p...
Sijtsema M, Stringer T, Hopman NEM, van der Graaf-van Bloois L, Duim B, van den Brom-Spierenburg A, Theelen M, Zomer A, Broens EM.Healthcare-associated infections (HAIs) associated with ESKAPEE pathogens are an emerging concern in equine hospitals, especially in the intensive care unit (ICU). To gain insight into the occurrence of HAIs and to identify potential reservoirs and transmission routes of ESKAPEE pathogens in an equine ICU, a pilot study of two periods (December 2022-January 2023 and April-June 2023) was performed, where patient and environmental samples were obtained upon ICU admission and discharge. A sampling and laboratory protocol for the detection and identification of different ESKAPEE pathogens and Salm...
Talib MT, Nasir A, Kashif M, Rahman A, Rehman AU, Akbar H, Nadeem A, Howe DK, Azam MN.The aim of this study was to determine the prevalence of anti-Neospora (N.) caninum and anti-N. hughesi antibodies in horses and to appraise the associated risk factors in the two central districts (Jhang and Toba Tek Singh) of Punjab Province, Pakistan. A total of 300 horse sera were analyzed for the presence of antibodies to Neospora spp. using a competitive ELISA. The overall prevalence of antibodies against Neospora species in horses was 25 % (75/300; 95 % CI 20.1-29.9). The prevalence of antibodies to N. caninum and N. hughesi species was 12.3 % (37/300; 95 % CI 8.6-16) and 19.3 % (5...
Martins AS, Romanowski TNA, Campos JS, Vieira RC, Silva TA, Borsanelli AC.Brucellosis is a zoonosis caused by bacteria of Brucella genus, which affects domestic and wild animals and humans. In horses, the infection can be caused by Brucella canis, Brucella suis or Brucella abortus, through the ingestion of contaminated food, contact of bacteria with skin wounds or through the respiratory tract, manifesting with signs such as fistulous withers and reduced performance. The present study aimed to evaluate the seroprevalence of Brucella abortus infection in equids in the state of Goiás. Sampling was carried out on 299 farms across 132 municipalities, with a total of 89...
Brys M, Claerebout E, Saey V, Chiers K.A cross-sectional study was conducted to estimate the prevalence of chorioptic mange affecting the distal legs of horses in Belgium, focusing on the association between mange and chronic progressive lymphedema (CPL) in Belgian draft horses. Clinical examinations and skin scrapings were performed on the distal legs of 156 Belgian draft horses and 142 Belgian warmblood horses. In the Belgian draft horse breed, 144 (92.31%) horses were infested with Chorioptes bovis mites, and 126 (80.77%) displayed clinical signs of CPL. CPL prevalence in draft horses aged < 1 year was 17.86%, while mites we...
Bain ME, Alsop EJ, Knox CA, Tweedie MA, Knottenbelt DC.Mycobacterium ulcerans infection in horses is under-reported. Objective: To document the successful multimodal treatment of M. ulcerans and highlight the need for further investigation due to the zoonotic nature of M. ulcerans with its related potential public health concerns. Methods: Case report CASE DESCRIPTION: A 14-year-old gelding in the Southeastern region of Australia was diagnosed with M. ulcerans infection, initially presenting as a non-healing wound of the right flank progressing to extensive necrotic ulceration. Ziehl-Neelsen and Wade-Fite stained incisional biopsies revealed large...
Peris MP, Serrano M, Romero A, García M, Halaihel N, Castillo JA, Gracia MJ.Equine piroplasmosis (EP), a tick-borne disease caused by Babesia caballi and Theileria equi, is of significant concern due to its impact on the international horse trade. According to standards established by the World Organisation for Animal Health (WOAH), horses imported from EP-endemic regions must have a certificate confirming negative serological and molecular test results. In EP-free countries, only seronegative horses are allowed to enter. This entails economic losses for endemic regions such as Spain. Our study aimed to assess the prevalence of B. caballi and T. equi in horses from no...
