Epidemiology in horses involves the study of the distribution and determinants of health-related states and events in equine populations. It encompasses the investigation of patterns, causes, and effects of diseases and health conditions within horse populations. This field of study aims to identify risk factors for disease and targets for preventive healthcare. Key components of equine epidemiology include disease surveillance, outbreak investigation, and the study of disease dynamics within herds or regions. Research in this area often focuses on infectious diseases, zoonotic diseases, and the impact of environmental factors on equine health. This page compiles peer-reviewed research studies and scholarly articles that explore various aspects of epidemiology in horses, including disease prevalence, transmission pathways, and strategies for disease prevention and control.
Hinrichsen SL, Yuen KY, Dryburgh EL, Bertin FR, Stewart AJ.Pituitary pars intermedia dysfunction (PPID) is diagnosed by increased basal or post thyrotropin-releasing hormone (TRH) stimulation ACTH concentrations. ACTH is known to be unstable; however, the effect of different temperatures and TRH stimulation on equine ACTH stability is poorly described. In total, 15 horses, including 8 PPID positive (ACTH > 35 pg/mL at baseline or >65 pg/mL 30 min after TRH stimulation), were divided into 2 groups: 9, including 5 PPID positive, with basal ACTH concentrations and 6, including 3 PPID positive, with post TRH stimulation ACTH concentrations. Whole bl...
Almazán C, Scimeca RC, Reichard MV, Mosqueda J.Babesia and Theileria are apicomplexan parasites that cause established and emerging diseases in humans, domestic and wild animals. These protozoans are transmitted by Ixodid ticks causing babesiosis or theileriosis, both characterized by fever, hemolytic anemia, jaundice, and splenomegaly. In North America (NA), the most common species affecting humans is B. microti, which is distributed in the Northeastern and Upper Midwestern United States (US), where the tick vector Ixodes scapularis is established. In livestock, B. bovis and B. bigemina are the most important pathogens causing bovine babe...
Abushhiwa MH, Elmeshreghi TN, Alrtib AM, Bennour EM, Oheida AH.Orthopedic diseases involving the forelimb fetlock joint of horses other than those used in professional racing have not been widely reported in the literature. One of these problems is the exostosis on the proximal forelimb phalanx (P1), which has not been reported previously in Western Libya. The study aimed to investigate the prevalence of P1 exostosis in traditional equestrian horses (known locally as Sarj horses) of different breeds in Libya that participated in a special social event and described its clinical findings radiographic appearance. The current study involved 60 horses admitte...
Bergmann F, Trachsel DS, Stoeckle SD, Bernis Sierra J, Lübke S, Groschup MH, Gehlen H, Ziegler U.Following the introduction of the West Nile virus (WNV) into eastern Germany in 2018, increasing infections have been diagnosed in birds, equines, and humans over time, while the spread of WNV into western Germany remained unclear. We screened 437 equine sera from 2018 to 2020, excluding vaccinated horses, collected from convenience sampled patients in the eastern and western parts of Germany, for WNV-specific antibodies (ELISAs followed by virus/specific neutralization tests) and genomes (RT-qPCRs). Clinical presentations, final diagnoses, and demographic data were also recorded. In the easte...
Pringle J, Aspán A, Riihimäki M.The value of repeated nasopharyngeal lavage (NPL) to detect silent carriers of Streptococcus equi has not been investigated. Objective: Determine if results of serial testing for S. equi by NPL predicts subsequent true carrier status as determined by both NPL and guttural pouch lavage. Methods: An outbreak of strangles with 100% morbidity in 41 mature Icelandic horses was followed prospectively to investigate development of silent carriers. All were initially positive to S. equi on NPL. The farm was closed to horse movement during the entire study. Methods: Prospective observational study. Tes...
Riley CB, Rogers CW, Thompson KR, Guiver D, Padalino B.Negative outcomes associated with the road transport of horses are a significant welfare issue. This study aimed to describe the injuries sustained by horses during road transport in New Zealand and factors associated with trauma while in transit. New Zealand horse industry participants were surveyed on their horse transport experiences and equine industry involvement. Participants were solicited through horse organisations. The data were tabulated, and a logistic regression was performed to identify significant ( < 0.05) factors associated with transport-related injury. In total, 201/1133 ...
Hain-Saunders NMR, Knight DR, Bruce M, Riley TV.Clostridioides (Clostridium) difficile presents a significant health risk to humans and animals. The complexity of the bacterial-host interaction affecting pathogenesis and disease development creates an ongoing challenge for epidemiological studies, control strategies and prevention planning. The recent emergence of human disease caused by strains of C. difficile found in animals adds to mounting evidence that C. difficile infection (CDI) may be a zoonosis. In equine populations, C. difficile is a known cause of diarrhoea and gastrointestinal inflammation, with considerable mortality and morb...
Hellings IR, Skjerve E, Karlstam E, Valheim M, Ihler CF, Fintl C.There are no reports on the number of fatalities or causes of death in the Norwegian and Swedish harness racehorses. Objective: The incidence rates (IRs), risk factors, and postmortem findings in horses that died or were euthanized associated with racing between 2014 and 2019 were investigated. Methods: Thirty-eight Standardbreds and 10 Norwegian-Swedish Coldblooded Trotters died or were euthanized associated with racing. A total of 816 085 race-starts were recorded. Methods: Incidence rates were calculated for both countries and horse breeds. Risk factors for sudden death were identified us...
Drabbe A, Janssens S, Blott S, Ducro BJ, Fontanel M, Francois L, Schurink A, Stinckens A, Lindgren G, Van Mol B, Pille F, Buys N, Velie BD.Osteochondrosis (OC) is an important skeletal disease causing profound welfare concerns in horses. Although numerous studies have explored the genetics underlying OC in various breeds, the Belgian Warmblood (BW) remains unstudied despite having a concerning prevalence of 32.0%. As a result, this study aimed to conduct genome-wide association (GWA) analyses to identify candidate variants associated with OC in BWs. To achieve this, blood samples and radiographs were collected from 407 Belgian Warmbloods registered to one of two BW studbooks (Belgisch Warmbloedpaard and Zangersheide), and genotyp...
Mahlobo-Shwabede SIC, Zishiri OT, Thekisoe OMM, Bakkes D, Bohloa L, Molomo M, Makalo MJR, Mahloane GR, Mtshali MS.A total of 3311 tick specimens were randomly collected from domestic animals including cattle, sheep, goats, horses, donkeys, and dogs from Lesotho districts namely, Berea, Butha-Buthe, Leribe, Mafeteng, Maseru, Mohale's Hoek, Mokhotlong, Qacha's Nek, Quthing and Thaba Tseka. Tick species were identified morphologically and verified by amplification and sequencing of the CO1 and 18S rRNA genes. Nine species were identified under different genera namely, Haemaphysalis elliptica 0.1% (n = 2), Hyalomma rufipes 2.6% (n = 87), Hy. truncatum 1.2% (n = 41), Otobius megnini 13.6% (n = 451), Rh...
Frosth S, Morris ERA, Wilson H, Frykberg L, Jacobsson K, Parkhill J, Flock JI, Wood T, Guss B, Aanensen DM, Boyle AG, Riihimäki M, Cohen ND....Streptococcus equi subspecies equi (S equi) is the cause of Strangles, one of the most prevalent diseases of horses worldwide. Variation within the immunodominant SeM protein has been documented, but a new eight-component fusion protein vaccine, Strangvac, does not contain live S equi or SeM and conservation of the antigens it contains have not been reported. Objective: To define the diversity of the eight Strangvac antigens across a diverse S equi population. Methods: Genomic description. Methods: Antigen sequences from the genomes of 759 S equi isolates from 19 countries, recovered between 1...
Chang QC, Hu Y, Wu TT, Ma XX, Jiang BG, Jia N, Wang AQ, Jiang JF. is a tick-borne pathogen that infects humans; however, the vertebrate hosts of this pathogen have not been clearly defined. Our molecular examination of spp. infecting mammals and ticks in China, identified the A, A, and 17KD gene sequences of in horses and their ticks. This indicates a role of horses in epidemiology.
Sharma D, Gupta S, Sethi K, Kumar S, Kumar R.Trypanosoma evansi, a hemoflagellate protozoan parasite, causes wasting disease called surra in wide range of animals. Although the organism has been reported from various parts of India, data generated from organized epidemiological study is still in infancy in majority states of India. In the present study, livestock of Himachal Pradesh, India, was targeted for epidemiological investigation of T. evansi infections. A total of 440 equines and 444 cattle serum samples were collected from four agro-climatic zones. Furthermore, serum samples of 280 buffaloes from three different agro-climatic zo...
Sahu A, Dhanze H, Singh V, Mehta D, Gupta M, Singh M, Vinod VK, Gulati BR.Japanese encephalitis (JE) is a re-emerging mosquito borne disease, for which equines are most susceptible amongst all animals. Detection of specific immunoglobulin 'M' (IgM) is considered as an ideal way to diagnose recent JE virus infection in equines due to low virus load and short-term viremia. The present study was undertaken to develop a sensitive and specific recombinant NS1 protein based indirect IgM-ELISA and IgM capture (MAC) ELISA to diagnose recent infection of JEV in equines. Indirect IgM ELISA was standardized with relative diagnostic sensitivity and specificity of 100% and 88.5%...
Merlin A, Ravinet N, Sévin C, Bernez-Romand M, Petry S, Delerue M, Briot L, Chauvin A, Tapprest J, Hébert L.Cyathostomins are considered as the most prevalent and pathogenic parasites of grazing horses. The development on pastures of the free-living stages of these gastrointestinal worms is particularly influenced by outdoor temperature. Understanding the bionomics of free-living stages is an important prerequisite to implement mathematical models designed to assess the parasitic risk for grazing equids. The aim of this study was to assess the effect of 3 constant temperatures under laboratory conditions (10 ± 1 °C, 23 ± 2 °C, 30 ± 2 °C) and one fluctuating temperature under outdoor c...
Morris ERA, Wu J, Bordin AI, Lawhon SD, Cohen ND.Streptococcus equi subsp. (SEE) is a host-restricted equine pathogen considered to have evolved from Streptococcus equi subsp. (SEZ). SEZ is promiscuous in host range and is commonly recovered from horses as a commensal. Comparison of a single strain each of SEE and SEZ using whole-genome sequencing, supplemented by PCR of selected genes in additional SEE and SEZ strains, was used to characterize the evolution of SEE. But the known genetic variability of SEZ warrants comparison of the whole genomes of multiple SEE and SEZ strains. To fill this knowledge gap, we utilized whole-genome sequenci...
Fairbanks EL, Brennan ML, Mertens PPC, Tildesley MJ, Daly JM.African horse sickness (AHS) is a vector-borne disease transmitted by Culicoides spp., endemic to sub-Saharan Africa. There have been many examples of historic and recent outbreaks in the Middle East, Asia and Europe. However, not much is known about infection dynamics and outbreak potential in these naive populations. In order to better inform a previously published ordinary differential equation model, we performed a systematic literature search to identify studies documenting experimental infection of naive (control) equids in vaccination trials. Data on the time until the onset of viraemia...
Ribeiro MG, de Morais ABC, Alves AC, Bolaños CAD, de Paula CL, Portilho FVR, de Nardi Júnior G, Lara GHB, de Souza Araújo Martins L, Moraes LS....Klebsiella species, particularly K. pneumoniae, are well-known opportunistic enterobacteria related to complexity of clinical infections in humans and animals, commonly refractory to conventional therapy. The domestic animals may represent a source of the pathogenic and multidrug-resistant Klebsiella species to humans. Nevertheless, most studies involving Klebsiella-induced infections in domestic animals are restricted to case reports or outbreaks. We retrospectively investigated selected epidemiological data, clinical aspects, and in vitro susceptibility pattern of 697 non-repetitive Klebsiel...
Chambers TM.Horses are the third major mammalian species, along with humans and swine, long known to be subject to acute upper respiratory disease from influenza A virus infection. The viruses responsible are subtype H7N7, which is believed extinct, and H3N8, which circulates worldwide. The equine influenza lineages are clearly divergent from avian influenza lineages of the same subtypes. Their genetic evolution and potential for interspecies transmission, as well as clinical features and epidemiology, are discussed. Equine influenza is spread internationally and vaccination is central to control efforts....
Mohammed R, Nader SM, Hamza DA, Sabry MA.Cryptococcosis is an opportunistic mycozoonosis of global significance in a wide variety of host species. In equines, cryptococcosis is uncommon, and sporadic cases have been reported with rhinitis, sinusitis, pneumonia, and meningitis. Cryptococcus spp. represents a potential risk for immunosuppressed and healthy persons. In Egypt, epidemiological data on cryptococcal infection in horses are limited. The current study was carried out to investigate the occurrence of Cryptococcus spp. in horses and its possible role in the epidemiology of such disease in Egypt. A total of 223 samples was colle...
Oliveira FAS, Castro RJS, de Oliveira JF, Barreto FM, Farias MPO, Marinho GLOC, Soares MJDS, Silva-Júnior A, Schwarz DGG.In Brazil, the horse is frequently used in cultural activities, sports, and in rural and urban work, implementing the economy in different social classes. Among the diseases in horses with zoonotic potential, rabies has been neglected in the country, increasing the risk of spreading the disease across borders. The present study evaluated the spatiotemporal distribution and temporal trend of rabies in horses in Brazil between 2010 and 2019. During this period, 1290 cases of rabies were detected in horses in Brazil, mainly in the states of São Paulo (21.7%) and Mato Grosso (13.3%). However, Esp...
Gomaa N, Elemiri M, Hegazy Y, Zeineldin M, Nassif M, Alcala-Canto Y, Barbabosa-Pliego A, Rivas-Caceres RR, Abdelmegeid M.A retrospective cohort study was conducted on two Egyptian horse farms with most of horses were suffered from abdominal pain to describe the associations between the occurrence of mycotoxicosis and equine colic. The farms owner complain was an unexpected increase in number of colic cases and deaths among horses. The association between colic and risk factors (sex, type of food either dry or mixed with roughages and hematobiochemical parameters) was compared using independent sample T-test. The associations between possible prognostic indicators for colic caused by mycotoxicosis was estimated u...
Radalj A, Milic N, Stevanovic O, Nisavic J.Nasal swabs originating from 112 apparently clinically healthy and unvaccinated horses of different age, breed and from diverse rearing conditions from Serbia and Bosnia and Herzegovina were examined for the presence of equine herpesviruses 1, 4 and 5 using multiplex nested PCR (Mn‑PCR) and virus isolation. The detected viruses were subsequently characterised by gB gene nucleotide sequencing and their phylogenetic analysis was performed. The infections with EHV‑1, EHV‑4, and EHV‑5 in the examined horse populations are apparently chronic, subclinical and persistent, whilst the shedding ...
Yoon J, Park T, Kim A, Song H, Park BJ, Ahn HS, Go HJ, Kim DH, Lee JB, Park SY, Song CS, Lee SW, Choi IS.Equine parvovirus-hepatitis (EqPV-H) and equine hepacivirus (EqHV) are etiologically associated with Theiler's disease (TD), causing fulminant equine hepatitis, but the transmission route and co-infection effect remain unclear. We determined EqPV-H and EqHV prevalence and coinfection rate in 160 serum and 114 faecal samples using nested polymerase chain reaction. Amino acid and nucleotide analyses were performed and phylogenetic trees were constructed. By measuring liver-specific parameters (AST, GGT, TBIL and A/G ratio), hepatopathological changes in viremia status were compared. We found a h...
Nguyen D, Vilela R, Miraglia BM, Vilela G, Jasem-Alali N, Rohn R, Glass R, Hansen RD, Mendoza L.To describe the geographic distribution of infections caused by Pythium insidiosum in dogs, horses, and other animal species in the US. For the last 20 years, we have collected data from cases of pythiosis in 1,150 horses, 467 dogs, and other species (59) from various geographic locations in the US. Due to lost data (from 2006 to 2016), the selected cases include years 2000 to 2005 and 2016 to 2020. The selection of cases was based on infected host clinical features, serum samples demonstrating strong positive anti-P insidiosum IgG titers in serologic assays, and positive results on ≥ 1 of t...
Nielsen SS, Bicout DJ, Calistri P, Canali E, Drewe JA, Garin-Bastuji B, Gonzales Rojas JL, Gortazar Schmidt C, Herskin M, Michel V, Miranda Chueca MA....In this opinion, the antimicrobial-resistant bacteria responsible for transmissible diseases that constitute a threat to the health of horses have been assessed. The assessment has been performed following a methodology composed of information collected via an extensive literature review and expert judgement. Details on the methodology used for this assessment are explained in a separate opinion. A global state of play of antimicrobial-resistant spp. spp. and subsp and subsp. and subsp. has been provided. Among those bacteria, EFSA identified , and with more than 66% certainty as the mo...
Rumfola E, Banse HE, Atkins M, McGowan CM, Ireland JL.Endocrinopathic laminitis is the most common cause of laminitis in the field. Insulin has recently been implicated as a key factor in development of endocrinopathic laminitis; however, it is unclear whether diagnostic, and treatment approaches reflect insights derived from recent research. This study sought to evaluate North American veterinary practitioners' approach to endocrinopathic laminitis in the field. Demographic information, approach to diagnosis, management, and prognosis of endocrinopathic laminitis, as well as factors influencing changes in approach to laminitis were collected. To...
Abdullah HHAM, Aboelsoued D, Farag TK, Abdel-Shafy S, Abdel Megeed KN, Parola P, Raoult D, Mediannikov O.Equine vector-borne diseases (EVBDs) are emerging and re-emerging diseases, and most of them are zoonotic. This study aimed to investigate EVBDs in equines and associated arthropods (ticks and flies) from Egypt using molecular analyses, in addition to a preliminary characterization of associated ticks and flies by the matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) and molecular techniques. In this study, 335 blood samples were obtained from equines that appeared to be in good health (320 horses and 15 donkeys) in Cairo and Beni Suef provinces, Egypt. From the same anima...
Lee H, Lee SH, Lee YR, Kim HY, Moon BY, Han JE, Rhee MH, Kwon OD, Kwak D.Enterocytozoon bieneusi is a microsporidian pathogen. Recently, the equestrian population is increasing in Korea. The horse-related zoonotic pathogens, including E. bieneusi, are concerns of public health. A total of 1,200 horse fecal samples were collected from riding centers and breeding farms in Jeju Island and inland areas. Of the fecal samples 15 (1.3%) were PCR positive for E. bieneusi. Interestingly, all positive samples came from Jeju Island. Diarrhea and infection in foals were related. Two genotypes (horse1, horse2) were identified as possible zoonotic groups requiring continuous mon...
Deardorff ER, Weaver SC.The mosquito Culex (Melanoconion) taeniopus is a proven vector of enzootic Venezuelan equine encephalitis virus (VEEV) subtype IE in Central America. It has been shown to be highly susceptible to infection by this subtype, and conversely to be highly refractory to infection by other VEEV subtypes. During the 1990s in southern coastal Mexico, two VEE epizootics in horses were attributed to subtype IE VEEV. These outbreaks were associated with VEEV strains with an altered infection phenotype for the epizootic mosquito vector, Aedes (Ochlerotatus) taeniorhynchus. To determine the infectivity for ...
Binz T, Lebelt J, Niemann H, Hagenau K.By reverse transcriptase/PCR amplification and subsequent sequence determination of the p24 gene, the relatedness of Borna disease virus (BDV) in various naturally infected animal species was determined. These results are indicative of a common ancestral virus pool and a remarkably low species barrier of BDV. Comparison of 11 sequences to that of tissue culture adapted virus revealed that the homology among all isolates was at least 96.2% at the nucleotide level, and 97% at the amino acid level. Viral sequences from sheep, donkey and horse were found to be not more distantly related to each ot...
Mughini-Gras L, Mulatti P, Severini F, Boccolini D, Romi R, Bongiorno G, Khoury C, Bianchi R, Montarsi F, Patregnani T, Bonfanti L, Rezza G....In Italy, West Nile virus (WNV) equine outbreaks have occurred annually since 2008. Characterizing WNV vector habitat requirements allows for the identification of areas at risk of viral amplification and transmission. Maxent-based ecological niche models were developed using literature records of 13 potential WNV Italian vector mosquito species to predict their habitat suitability range and to investigate possible geographical associations with WNV equine outbreak occurrence in Italy from 2008 to 2010. The contribution of different environmental variables to the niche models was also assessed...
Guerrero-Carvajal F, Bravo-Barriga D, Martín-Cuervo M, Aguilera-Sepúlveda P, Ferraguti M, Jiménez-Clavero MÁ, Llorente F, Alonso JM, Frontera E.West Nile virus (WNV) is a mosquito-borne emerging virus in Europe with capacity to cause neurological complications such as encephalitis or meningoencephalitis in humans, birds or equids. In Spain, WNV is actively circulating in mosquitoes, birds and horses in different regions, but never has been deeply studied in Extremadura. Therefore, the aim of this study was to evaluate the seroprevalence of WNV in equids of those areas and to analyse the risk factors associated with exposure to the virus. A total of 199 out of 725 equids presented antibodies against WNV by competition ELISA (27.45%), w...
Salim B, Bakheit MA, Kamau J, Nakamura I, Sugimoto C.This is a molecular epidemiological investigation on Theileria equi, a causative agent of equine piroplasmosis. Blood samples were collected from 127 horses from different geographical locations in Sudan. The small subunit of rRNA gene (18S; ~1,600 bp) was amplified from 20 positive field samples and subsequently subjected to direct sequencing and analysis to reveal possible strain differences and the presence of a novel species or genotypes. Sequences were compared with published sequences mainly from South African and Spanish isolates. Eleven distinct T. equi sequences within 18S rRNA gene w...
Henderson BE, Chappell WA, Johnston JG, Sudia WD.Henderson, B. E., W. A. Chappell, J. G. Johnston, Jr. and W. D. Sudia (CDC, Atlanta, Ga. 30333). Experimental Infection of horses with three strains of Venezuelan equine encephalomyelitis virus. I. Clinical and virological studies. Amer J Epidem 93: 194–205, 1971.—Clinical effect, viremias and antibody responses were compared in horses inoculated with the following strains of Venezuelan equine encephalomyelitis (VEE) virus: Fe3-7C, isolated from Culex (Melano-conion) spp. mosquitoes collected In 1963 in the Florida Everglades; TC-83, the Fort Detrick live, attenuated vaccine strain; and GJ...
Clegg PD.Tendon and ligament injuries continue to be one of the most frequent causes of orthopaedic injury and early retirement in the Thoroughbred racehorse. In the UK, the Horserace Betting Levy Board has invested considerable research funding in the last decade in order to investigate aspects of tendon epidemiology, biology and therapy, in order to decrease both the welfare and economic consequence of such injuries. This review summarises key aspects of this research effort and identifies specific research directions for the future.
Ocansey BK, Kosmidis C, Agyei M, Dorkenoo AM, Ayanlowo OO, Oladele RO, Darre T, Denning DW.Histoplasmosis is a chronic granulomatous disease caused by the thermally dimorphic fungus Histoplasma capsulatum. The 2 variants Histoplasma capsulatum var. capsulatum (Hcc) and Histoplasma capsulatum var. duboisii (Hcd) causes infection in humans and commonly termed classical or American histoplasmosis and African histoplasmosis, respectively. Histoplasma capsulatum var. farciminosum (Hcf) affects equines. In recent times, there have been heightened sensitization on fungal infections such as histoplasmosis in Africa, aimed at improving awareness among relevant stakeholders, particularly heal...
Wagnerová P, Sak B, McEvoy J, Rost M, Matysiak AP, Ježková J, Kváč M.Faecal samples were collected from 352 horses on 23 farms operating under six different management systems in the Czech Republic and Poland during 2011 and 2012. Farms were selected without previous knowledge of parasitological status. All faecal samples were screened for Cryptosporidium spp. presence using microscopy, following aniline-carbol-methyl violet staining and PCR analysis of the small-subunit (SSU) rRNA and the 60-kDa glycoprotein (gp60) genes. Cryptosporidium muris-positive samples were additionally genotyped at four minisatellite markers: MS1 (encoding a hypothetical protein), MS2...
van Maanen C, Bruin G, de Boer-Luijtze E, Smolders G, de Boer GF.The purpose of the study was twofold. First, using two groups of 22 foals each, we investigated the extent to which maternal antibodies interfere with the humoral response against equine influenza. The foals were born to mares that had been vaccinated twice yearly against influenza since 1982. Foals of group I were vaccinated three times at early ages (12, 16, and 32 weeks of age), and foals of group II were likewise vaccinated but a later ages (24, 28, and 44 weeks of age). After the first and second vaccinations, neither group showed an increase in antibodies that inhibit haemagglutination. ...
Laatamna AE, Wagnerová P, Sak B, Květoňová D, Aissi M, Rost M, Kváč M.Faecal samples from two horse farms in Algeria keeping Arabian, Thoroughbred, and Barb horses were examined for the presence of Cryptosporidium in 2010-2011. A total of 138 faecal samples (16 from a farm keeping 50 animals and 122 from a farm with 267 horses) were screened for Cryptosporidium spp. infection using molecular tools. DNA was extracted from all samples. Nested PCR was performed to amplify fragments of the SSU rDNA and gp60 genes to determine the presence of Cryptosporidium species and genotypes. Sequence analyses of SSU and gp60 genes revealed four animals positive for the presence...
Halbert ND, Reitzel RA, Martens RJ, Cohen ND.To evaluate sensitivity and specificity of a multiplex polymerase chain reaction (PCR) assay for simultaneous detection of Rhodococcus equi and differentiation of strains that contain the virulence-associated gene (vapA) from strains that do not. Methods: 187 isolates of R equi from equine and nonequine tissue and environmental specimens and 27 isolates of bacterial species genetically or morphologically similar to R equi. Methods: The multiplex PCR assay included 3 gene targets: a universal 311-bp bacterial 16S ribosomal RNA amplicon (positive internal control), a 959-bp R equi-specific targe...
Guthrie AJ, Stevens KB, Bosman PP.Equine-2 influenza A virus (H3N8) infection first occurred among naïve horses in South Africa in December 1986. The virus was introduced following the importation of six horses from the United States of America. While the release of in-contact horses from quarantine three days after the arrival of these six horses played a role in the rapid spread of the disease in South Africa, other outbreaks of disease were associated with viral introduction by personnel or contaminated instruments. The control measures and implications of the introduction of equine influenza to South Africa are also discu...
Timoney PJ, McCollum WH, Murphy TW, Roberts AW, Willard JG, Carswell GD.The carrier state has been confirmed virologically in Thoroughbred and non-Thoroughbred stallions naturally infected with equine arteritis virus (EAV). Short-term or convalescent and long-term carriers occur. The frequency rate of the long-term carrier state in Thoroughbreds was high, averaging 33.9% among the three groups of stallions under study. While the convalescent carrier state only lasted a few weeks after clinical recovery, the long-term carrier state could persist for years. There was evidence, however, that not all such carriers might remain persistently infected for life. Carrier s...
Renshaw RW, Glaser AL, Van Campen H, Weiland F, Dubovi EJ.A virus that could not be identified as a previously known equine virus was isolated from the mononuclear cells of a horse. Electron microscopy revealed enveloped virions with nucleocapsid structures characteristic of viruses in the Paramyxoviridae family. The virus failed to hemabsorb chicken or guinea pig red blood cells and lacked neuraminidase activity. Two viral genes were isolated from a cDNA expression library. Multiple sequence alignments of one gene indicated an average identity of 45% as compared to Morbillivirus N protein sequences. A weaker relationship was found with Tupaia paramy...
Havlik HS.Equestrian sports continue to grow in popularity in the Unites States and abroad, with an estimated 30 million people riding horses annually in the United States alone. Approximately one in five of these riders will suffer a serious injury during their riding career, requiring medical care and potentially hospitalization. Riding carries with it an implicit risk of injury associated with the unpredictability of the animals, the rider's head being positioned approximately 9 feet off the ground, and traveling unrestrained at speeds up to 40 mph. This article reviews common equestrian injuries, ep...
Rapoport A, Aharonson-Raz K, Berlin D, Tal S, Gottlieb Y, Klement E, Steinman A.Equine piroplasmosis imposes great concerns for the equine industry regarding international horse movement, and therefore requires reliable diagnostic tools. Recent studies from South Africa and Jordan, including a preliminary study in Israel, reported extremely low seroprevalence to Babesia caballi (B. caballi) (0-1%) using the acceptable rhoptry-associated protein-1 (RAP-1) cELISA. In accordance with the study from South Africa demonstrating a significant heterogeneity in the rap-1 gene sequence of South African B. caballi isolates, the objectives of this study were to phylogenetically chara...
Powell DG, Watkins KL, Li PH, Shortridge KF.Equine-2 influenza virus A (H3N8) infection occurred among vaccinated thoroughbred horses in Hong Kong during November and December 1992. The outbreak was unique in that it occurred among a large population stabled under intensive conditions. It resulted in the postponement of seven race meetings over a period of 32 days. The outbreak originated after the importation of horses 25 to 32 days before any clinical signs were reported. Vaccination did not prevent 75 per cent of the population from becoming infected, and half the infected horses developed clinical signs. Vaccination did, however, co...
Gilkerson JR, Bailey KE, Diaz-Méndez A, Hartley CA.Many viral agents have been associated with respiratory disease of the horse. The most important viral causes of respiratory disease in horses are equine influenza and the equine alphaherpesviruses. Agents such as equine viral arteritis virus, African horse sickness virus, and Hendra virus establish systemic infections. Clinical signs of disease resulting from infection with these agents can manifest as respiratory disease, but the respiratory tract is not the major body system affected by these viruses. Treatment of viral respiratory disease is generally limited to supportive therapies, where...
Marsh GA, Todd S, Foord A, Hansson E, Davies K, Wright L, Morrissy C, Halpin K, Middleton D, Field HE, Daniels P, Wang LF.Bat-to-horse transmission of Hendra virus has occurred at least 14 times. Although clinical signs in horses have differed, genome sequencing has demonstrated little variation among the isolates. Our sequencing of 5 isolates from recent Hendra virus outbreaks in horses found no correlation between sequences and time or geographic location of outbreaks.
Quirin R, Salas M, Zientara S, Zeller H, Labie J, Murri S, Lefrançois T, Petitclerc M, Martinez D.To determine whether West Nile virus (WNV) had reached the archipelago of Guadeloupe, a serologic study in horses and birds was conducted in 2002. Immunoglobulin (Ig) G, IgM, enzyme-linked immunosorbent assay, and seroneutralization tests identified WNV infection in horses and chickens. Six months later, a high rate of seroconversion was observed in horses.
Xu Z, Kang X, Han P, Du P, Li L, Zheng A, Deng C, Qi J, Zhao X, Wang Q, Liu K, Gao GF.The origin and host range of SARS-CoV-2, the causative agent of coronavirus disease 2019 (COVID-19), are important scientific questions as they might provide insight into understanding of the potential future spillover to infect humans. Here, we tested the binding between equine angiotensin converting enzyme 2 (eqACE2) and the receptor binding domains (RBDs) of SARS-CoV, SARS-CoV-2 prototype (PT) and variant of concerns (VOCs), as well as their close relatives bat-origin coronavirus (CoV) RaTG13 and pangolin-origin CoVs GX/P2V/2017 and GD/1/2019. We also determined the crystal structures of eq...
Chaichanasiriwithaya W, Rikihisa Y, Yamamoto S, Reed S, Crawford TB, Perryman LE, Palmer GH.Ehrlichia risticii causes an acute infectious disease in horses called Potomac horse fever. To investigate the biological diversity of E. risticii organisms, nine E. risticii isolates derived from the peripheral blood monocytes of clinically sick horses in Ohio and Kentucky during the summers of 1991 and 1993 were compared with Illinois and Virginia isolates originally obtained from horses in Maryland in 1984. Seven of the nine isolates (081, 606, 380, 679, As, Co, and Ov) formed large morulae (tightly packed inclusions of ehrlichial organisms). The remaining isolates, including 1984 isolates,...
French NP, Smith J, Edwards GB, Proudman CJ.The reason for undertaking this study was that postoperative complications of colic surgery lead to patient discomfort, prolonged hospitalisation and increased cost. Potential risk factors for the 6 most common postoperative complications (jugular thrombosis, ileus, re-laparotomy, wound suppuration, incisional herniation and colic) were evaluated using multivariable models. Jugular thrombosis was associated significantly with heart rate greater than 60 beats/min and with increased packed cell volume (PCV) at admission. The risk of postoperative ileus also increased with increasing PCV at admis...
Bengis RG, Frean J.Anthrax is a peracute, acute or subacute multispecies bacterial infection that occurs on many continents. It is one of the oldest infectious diseases known; the biblical fifth and sixth plagues (Exodus chapters 7 to 9) that affected first livestock and then humans were probably anthrax. From the earliest historical records until development of an effective vaccine midway through the 20th Century, anthrax was one of the foremost causes of uncontrolled mortality in cattle, sheep, goats, horses and pigs, with 'spill over' into humans, worldwide. With the development of the Sterne spore vaccine, a...
