Infectious diseases in horses encompass a range of illnesses caused by bacteria, viruses, fungi, or parasites. These diseases can affect various systems within the equine body, leading to symptoms that range from mild discomfort to severe systemic illness. Common infectious diseases in horses include equine influenza, strangles, equine herpesvirus, and West Nile virus. These diseases can be transmitted through direct contact with infected animals, contaminated surfaces, or vectors such as insects. Understanding the mechanisms of transmission, pathogenesis, and immune response is essential for effective prevention and control. This page compiles peer-reviewed research studies and scholarly articles that explore the epidemiology, diagnosis, treatment, and management of infectious diseases in horses.
Sacco SC, Ortega J, Navarro MA, Fresneda KC, Anderson M, Woods LW, Moore J, Uzal FA.Gas gangrene occurs in several animal species and is caused by one or more clostridial species. In horses, the disease is most often caused by Clostridium perfringens type A. Although Clostridium sordellii has been associated with gas gangrene in ruminants and humans, cases of the disease associated with this microorganism have not been described in horses, to our knowledge. We report herein 8 cases of gas gangrene caused by C. sordellii in horses. These cases were characterized by myonecrosis and cellulitis, associated with systemic changes suggestive of toxic shock. The diagnosis was confirm...
Rickards KJ, Thiemann AK.Donkeys suffer from the same respiratory diseases as horses; however, owing to their nonathletic nature many conditions can present in a more advanced state before becoming clinically apparent. Anatomically, their respiratory tract is similar to the horse, with certain species-specific differences that are important to be aware of. Often donkeys do not receive the same level of routine care as horses, so many are not vaccinated against respiratory pathogens such as influenza or herpesviruses. Donkeys can act as a reservoir for certain infectious and parasitic respiratory diseases and the inter...
Sukmawinata E, Sato W, Mitoma S, Kanda T, Kusano K, Kambayashi Y, Sato T, Ishikawa Y, Goto Y, Uemura R, Sueyoshi M.Extended-spectrum β-lactamase-producing Escherichia coli (ESBLEC) have become a major health concern in both human and veterinary medicine. These bacteria could become a critical problem in equine medicine due to the limited number of antimicrobial drugs available. However, there are no previous reports of ESBLEC isolated from horses in Japan. The objectives of this study were to investigate the occurrence of ESBLEC isolated from feces in healthy Thoroughbred racehorses in Japan. Feces samples were collected from 147 healthy Thoroughbred racehorses by equine veterinarians at the Japan Racing ...
Ueno Y, Uemura R, Niwa H, Higuchi T, Sekiguchi S, Sasaki Y, Sueyoshi M.Equine proliferative enteropathy (EPE) caused by Lawsonia intracellularis is characterized by hypoproteinemia. There are currently no reliable reports that provide a reference value for the total serum protein (TP) concentration to clinically diagnose EPE. The objective of this study was to statistically determine the reference value. Feces and sera of 99 foals with EPE-like clinical signs and of 35 healthy foals were obtained. The samples were used for specific-gene detection of L. intracellularis, TP measurement, and specific-antibody detection against L. intracellularis. Based on these resu...
Wernery U, Rodriguez Caveney M, Wernery R, Raghavan R, Laroucau K, Syriac G, Thomas SM, John J, Joseph M, Jose S, Joseph S, Woo P.Six horses were challenged experimentally with a strain of Burkholderia pseudomallei isolated from a fatal case of the infection in a dromedary camel years earlier in the Emirate of Dubai. Three horses were inoculated subcutaneously and in 3 the bacterium was administered by the oral route. Four of the horses became serologically positive based on reactions to one or more of the OIE described tests for glanders. B. pseudomallei was re-isolated from the 4 serological positive horses. Only one of the subcutaneously infected horses, developed fever for 3 days. The white blood cell values and the ...
Browne C, Medlock JM.Last summer saw an unusually high number of cases of West Nile fever in horses and people in south and south-east Europe, but it is too early to tell if this was a one-off increase or a sign of things to come. Here, , , and discuss the various West Nile fever surveillance and control mechanisms in place in the UK.
Schoster A, Kunz T, Lauper M, Graubner C, Schmitt S, Weese JS.Overgrowth of enteric clostridia in dysbiosis in horses with colic is presumed but scarcely investigated. The objective was to provide prevalence data of Clostridium difficile and Clostridium perfringens in horses with and without gastrointestinal disease in Switzerland, and investigate microbiota differences between C. difficile shedders and non-shedders. Fecal samples were taken from healthy horses (n = 103), horses with colic (n = 98) and horses with diarrhea (n = 151). Colic horses were sampled on three days. Selective enrichment culture and molecular typing for C. difficile an...
Gür S, Gürçay M, Seyrek A.Bovine enteroviruses (BEV) are members of Enterovirus genus of the family Picornaviridae. BEV1 has a broad host spectrum, including humans. The virus usually causes subclinical infection, but fatal/severe cases have also been reported in different animal species. There is quite limited data regarding BEV1 in humans. The purpose of this study is to investigate human infection and to identify possible risk factors for viral exposure. For this purpose, blood serum samples (n=1,526) were collected from a city center and nearby villagers simultaneously from humans and farm animals in Elazig provinc...
Bosco-Lauth AM, Bowen RA.West Nile virus (WNV) (Flaviviridae: Flavivirus) was discovered in Africa more than 80 yr ago and became recognized as an avian pathogen and a cause of neurologic disease in horses largely during periodic incursions into Europe. Introduction of WNV into North America stimulated great anxiety, particularly in the equine industry, but also for pet owners and livestock producers concerned about the effect of WNV on other domestic animals. Numerous subsequent studies of naturally occurring and experimentally induced disease greatly expanded our understanding of the host range and clinical conseque...
To evaluate the etiology of skeletal changes noted in equid vertebrae from a 19- century context near Belgrade, Serbia. A vertebral column consisting of 15 fused thoracic vertebrae (T2-T16), with right ribs fused to T4 and T5 and small remnants of ribs articulating with T4, T5 and T6 on the left side were accidentally recovered during industrial exploitation of sand. The specimen was subjected to morphological analysis and collagen fingerprinting by mass spectrometry for species identification. In order to determine the absolute temporal context, radiocarbon dating was employed. Pathological c...
Pechacek D, Hwangbo M, Moreland R, Liu M, Ramsey J. 4s is a Gram-negative bacterium found in the equine intestinal ecosystem alongside diverse other coliform bacteria and bacteriophages. This announcement describes the complete genome of the T7-like 4s podophage Penshu1. From its 39,263-bp genome, 54 protein-encoding genes and a 179-bp terminal repeat were predicted.
Nemoto M, Tamura N, Bannai H, Tsujimura K, Kokado H, Ohta M, Yamanaka T.Baloxavir marboxil (BXM), an inhibitor of the cap-dependent endonuclease of the influenza virus polymerase acidic protein (PA), exerts an antiviral effect against influenza A virus. It has been available in Japan since March 2018. This study evaluated the antiviral efficacy of BXM against equine influenza A virus (EIV) by an experimental challenge study using horses. Six horses were experimentally inoculated with EIV, and BXM was administered to the three horses at 2 days post inoculation. Horses treated with BXM showed milder clinical signs than horses without treatment and shed less virus. T...
Willingham-Lane JM, Berghaus LJ, Berghaus RD, Hart KA, Giguère S.The soil-dwelling, saprophytic actinomycete is a facultative intracellular pathogen of macrophages and causes severe bronchopneumonia when inhaled by susceptible foals. Standard treatment for disease is dual-antimicrobial therapy with a macrolide and rifampin. Thoracic ultrasonography and early treatment with antimicrobials prior to the development of clinical signs are used as means of controlling endemic infection on many farms. Concurrently with the increased use of macrolides and rifampin for chemoprophylaxis and the treatment of subclinically affected foals, a significant increase in t...
Yazdansetad S, Mosavari N, Tadayon K, Mehregan I.Burkholderia mallei is the leading cause of glanders, a highly transmittable and an OIE-notifiable disease of equidae. Despite the importance of B. mallei, little is known about serodiagnosis of glanders. The present study aimed to develop an immunoblotting assay based on whole-cell proteome of B. mallei to enable accurate serodiagnosis of glanders. Methods: Three farm horses were subcutaneously immunized with a crude suspension (106 cfu/ml) of heat-inactivated B. mallei formulated with incomplete Freund's adjuvant (IFA) to achieve a hyperimmune sera panel. The immunization was done for 1, 14 ...
Preziuso S, Sgorbini M, Marmorini P, Cuteri V.This study investigates the genetic variability of the equid alphaherpesvirus type 1 (EHV-1), a virus in horses, by evaluating four specific genes (ORF30, ORF33, ORF34, and ORF68) in Italian horse […]
Dennis SJ, Meyers AE, Hitzeroth II, Rybicki EP.African horse sickness is a devastating disease that causes great suffering and many fatalities amongst horses in sub-Saharan Africa. It is caused by nine different serotypes of the orbivirus African horse sickness virus (AHSV) and it is spread by Culicoid midges. The disease has significant economic consequences for the equine industry both in southern Africa and increasingly further afield as the geographic distribution of the midge vector broadens with global warming and climate change. Live attenuated vaccines (LAV) have been used with relative success for many decades but carry the risk o...
Tyrrell JD, Qurollo BA, Tornquist SJ, Schlaich KG, Kelsey J, Chandrashekar R, Breitschwerdt EB.Certain vector-borne organisms serve as etiological agents of equine disease. After previously identifying a new Ehrlichia species in horses from Mérida, we aimed to determine the infection frequency and screen for a wide range of vector-borne organisms from 93 tick-exposed, Ehrlichia seropositive horses in this region. PCR assays were performed to identify infection by organisms within the following genera: Anaplasma, Babesia, Bartonella, Ehrlichia, Leishmania, Mycoplasma, Neorickettsia, Rickettsia and Theileria. Overall, 90/93 horses (96.8%) were infected with one or more vector-borne organ...
Gill GS, Singh BB, Dhand NK, Aulakh RS, Sandhu BS, Ward MP, Brookes VJ.Rabies is a devastating zoonotic disease of mammals that causes encephalitis and death. It is endemic in India, with an estimated annual 20,000 human deaths (one-third of the global rabies burden). The magnitude of animal rabies incidence is unknown. In four sub-districts of Punjab, India, we monitored canine and livestock populations from August 15, 2016 to August 14, 2017. Demographic, clinical and rabies diagnostic laboratory (RDL) data were collected from suspected cases of rabies. The annual incidence rate / 10,000 animal years at risk (95% CI) in each sub-district was estimated for each ...
Di Rubbo A, McNabb L, Klein R, White JR, Colling A, Dimitrov DS, Broder CC, Middleton D, Lunt RA.Maintenance of Hendra virus (HeV) in pteropid bat populations has been associated with spillover events in horses, humans and dogs. Experimental studies have demonstrated infections for several other species including guinea pigs, cats and ferrets. The criteria of a sensitive and specific serological test that is effective for a range of species, but which does not require use of live virus, has not been satisfactorily addressed by currently available tests. We have evaluated the use of two HeV neutralizing monoclonal antibodies (mAbs) in a blocking format enzyme-linked immunosorbent assay (bE...
Gaudaire D, Lazić S, Lupulović D, Petrovic T, Lazić G, Berthet N, Hans A.Here, we report the first whole-genome sequence of an equine arteritis virus (EAV) strain, RS1, isolated from the semen of a Lipizzaner stallion held in the Vojvodina region of Serbia.
León B, Jiménez C, González R, Ramirez-Carvajal L.The first complete coding sequence of the Venezuelan equine encephalitis virus IE, isolated from a Costa Rican mare with severe encephalitis, was confirmed by histological and viral whole-genome analyses. The isolated virus grouped in the Pacific cluster.
Vianna AM, Santos AC, Cunha RC, de Souza Stori de Lara AP, Weege GB, Leivas Leite FP.Equine theileriosis is a severe equine disease caused by the protozoan Theileria equi, which is prevalent in tropical and subtropical areas. In this study, a recombinant equi merozoite antigen-2 (rEMA-2) of T. equi was used as an immunogen. Two groups of 10 mice each were divided into control and vaccinated groups. Sixty mares seronegative for theileriosis were divided in two groups, one vaccinated and another group as a control animal. Mice and mares of the vaccinated groups were inoculated with 150 μL of the vaccine containing 50 μg of rEMA-2 and 2 mL of the vaccine containing 200 ...
Lechmann J, Schoster A, Ernstberger M, Fouché N, Fraefel C, Bachofen C.Equid alphaherpesvirus 1 (EHV-1) infections can have a major impact on the horse industry and equine welfare by causing abortion or respiratory or neurologic disease. A single nucleotide polymorphism (A→G) in open reading frame (ORF) 30, encoding the catalytic subunit of the DNA polymerase, has been shown to be a strong predictive marker for neuropathogenicity. Given that a previously established real-time PCR (rtPCR) protocol yielded unsatisfactory results concerning determination of the EHV-1 genotype, we developed and evaluated a new conventional PCR protocol enabling identification of th...
Tirosh-Levy S, Gottlieb Y, Arieli O, Mazuz ML, King R, Horowitz I, Steinman A.Equine piroplasmosis (EP) is an important tick-borne disease of equids, caused by Theileria equi and Babesia caballi. It is endemic in most parts of the world, including Israel, and has clinical and economic consequences. This study was set to evaluate the presence of EP parasites in domestic donkeys and in wild equids in Israel and the Palestinian Authority (PA). To assess subclinical EP infection in 98 domestic donkeys (Equus africanus asinus), 9 Asiatic wild donkeys (Equus hemionus), 8 zebras (Equus quagga), 7 African wild donkeys (Equus africanus) and 5 mules, were tested using PCR and qPC...
Bueno I, Pearce P, Dunowska M. To estimate the frequency of infection with equine herpesvirus type-1 (EHV-1) among horses from the central North Island of New Zealand, including the frequency of detection of the D genotype. Samples of retropharyngeal lymph nodes (RLN) and submandibular lymph nodes (SLN) were dissected from the heads of 63 horses that were humanely killed for various unrelated reasons between March and November 2015. DNA extracted from these tissues was subjected to enrichment for EHV-1 sequences by hybridisation with biotin-labelled EHV-1 specific probe, followed by recovery of EHV-1 sequences on streptavi...
Selmi R, Dhibi M, Ben Said M, Ben Yahia H, Abdelaali H, Ameur H, Baccouche S, Gritli A, Mhadhbi M.Livestock constitute habitual hosts and carriers for several infectious pathogens which may represent a serious public health concern affecting the readiness of military forces and lead to wide economic losses. The present report aimed to investigate the prevalence of some haemopathogens infecting military livestock, particularly, dromedaries, sheep and horses using Giemsa-stained blood smears. A total of 300 animals (100 from each species) were selected, clinically examined and sampled. Trypanosoma spp. (22.0%), Anaplasma spp. (17.0%) and Babesia spp. (1.0%) were identified in camels' blood. ...
Prutton JSW, Barnum S, Pusterla N.Equine coronavirus (ECoV) is considered an emerging enteric virus with reported morbidity rates ranging from 10 to 83% and fatality rates ranging from 7 to 27% in adult horses; a vaccine for ECoV is currently not available. This study investigated the safety, humoral response and viral shedding in horses inoculated with a commercially available modified-live bovine coronavirus (BCoV) vaccine. Twelve healthy adult horses were vaccinated twice, 3 weeks apart, either orally, intranasally or intrarectally. Two healthy unvaccinated horses served as sentinel controls. Following each vaccine adminis...
Rusnak JM, Glass PJ, Weaver SC, Sabourin CL, Glenn AM, Klimstra W, Badorrek CS, Nasar F, Ward LA.Licensure of a vaccine to protect against aerosolized Venezuelan equine encephalitis virus (VEEV) requires use of the U.S. Food and Drug Administration (FDA) Animal Rule to assess vaccine efficacy as human studies are not feasible or ethical. An approach to selecting VEEV challenge strains for use under the Animal Rule was developed, taking into account Department of Defense (DOD) vaccine requirements, FDA Animal Rule guidelines, strain availability, and lessons learned from the generation of filovirus challenge agents within the Filovirus Animal Nonclinical Group (FANG). Initial down-selectio...
Murphy RJT, Ramsay JP, Lee YT, Pang S, O'Dea MA, Pearson JC, Axon JE, Raby E, Abdulgader SM, Whitelaw A, Coombs GW.Staphylococcus aureus is a serious human and animal pathogen. Multilocus sequence type 612 (ST612) is the dominant methicillin-resistant S. aureus (MRSA) clone in certain South African hospitals and is sporadically isolated from horses and horse-associated veterinarians in Australia. Colonisation and infection by ST612-MRSA is increasing in Western Australia. Whole-genome sequencing was performed for 51 isolates of ST612-MRSA from Western Australian patients and healthcare workers, South African hospital patients, Australian veterinarians and New South Wales horses. Core genome phylogenies sug...
Fedorka CE, Ball BA, Scoggin KE, Loux SC, Troedsson MHT, Adams AA.Ascending placentitis is one of the leading causes of abortion in the horse. Minimal work has focused on its effect on fetal fluids or the antenatal immune response of the fetus. Placentitis was induced via transcervical inoculation of Streptococcus equi ssp Zooepidemicus, and fluids/serum/tissues were collected 4-6 days later following euthanasia. Cytokine concentrations were detected using a multiplex immunoassay within fetal fluids (amniotic and allantoic) and serum (maternal and fetal) in inoculated and control mares. In addition, tissues from fetal (spleen, liver, lung, umbilicus, amnioa...
Nyaoke AC, Navarro MA, Beingesser J, Uzal FA.A 14-y-old bay Quarter Horse gelding was presented with progressive neurologic signs, elevated rectal temperature, and icterus for 3 d prior to death. Postmortem examination revealed icterus, large amounts of serosanguineous fluid in the abdominal cavity, widespread petechiae and ecchymoses in several organs, and a large, pale, and well-demarcated focus of necrosis in the liver. Histologically, there was coagulative necrosis surrounded by a rim of inflammatory cells and large numbers of gram-positive rods, which were identified as Clostridium novyi by immunohistochemistry. Liver samples tested...
Dubey JP, Murata FHA, Cerqueira-Cézar CK, Kwok OCH.Toxoplasma gondii infections are common in humans and animals worldwide. The present review summarizes worldwide information on the prevalence of clinical and subclinical infections, epidemiology, and genetic diversity of T. gondii in horses, donkeys and other equids in the past decade. This review will be of interest to biologists, parasitologists, veterinarians, and public health workers.
Whitwell KE, Blunden AS.In 1988 an outbreak of the paralytic form of Equid herpesvirus type 1 (EHV-1) infection occurred on a stud farm and several animals died. This provided an opportunity to perform detailed pathological investigations to gain insights into the pathogenesis of this spontaneous disease. Two paretic mares, three foals, an aborted foetus and its non-paretic dam were examined. The endotheliotropism of the virus was clearly demonstrated by the use of an indirect immunoperoxidase (IP) stain. At autopsy, evidence of viral infection was widespread in the foetus and foals, but limited or absent in the mare...
Olitsky PK, Cox HR, Syverton JT.We have studied certain properties, additional to those previously described (3), of the virus of vesicular stomatitis of horses, and of the characteristic biological reactions of the virus of equine encephalomyelitis. It has been found that the virus of stomatitis, ordinarily dermotropic, can acquire neurotropism and the neurotropic encephalomyelitis virus can, in turn, be rendered dermotropic in its action. The neurotropism in both instances is associated with definite, although not pronounced, viscerotropism. Both viruses can bring about a similar infection in the white mouse, rat, guinea p...
Al-Kass Z, Spergser J, Aurich C, Kuhl J, Schmidt K, Morrell JM.Bacteria contaminate semen during collection and handling. The objective of this study was to identify the bacteria in pony stallion semen, the effects of antibiotics included in commercial semen extenders (lincomycin and spectinomycin) and the effect of modified single layer centrifugation (MSLC), on bacterial load. Ejaculates from six pony stallions, 3 ejaculates per animal, were extended in EquiPlus extender either with or without antibiotics. Aliquots were processed by MSLC to form four treatment groups: control and MSLC with antibiotics (CA and SA, respectively) and control and MSLC witho...
Gosztonyi G, Ludwig H.The brains of eight horses that had suffered from natural Borna disease were examined with virologic, immunohistological, and electron-microscopic methods. All brains harbored infectious virus as shown by inoculation of experimental animals. Regional assessment of the infectivity exhibited the highest titers in the hippocampus and piriform cortex and the lowest in the cerebellum. Conventional histology yielded pathologic alterations very similar to those of the classical description of the disease. Immunohistology demonstrated the highest amounts of Borna disease virus-specific antigen in the ...
Laroucau K, Aaziz R, Vorimore F, Varghese K, Deshayes T, Bertin C, Delannoy S, Sami AM, Al Batel M, El Shorbagy M, Almutawaa KAW, Alanezi SJ....Glanders is a contagious zoonotic disease caused by Burkholderia mallei. Following the detection of glanders positive horses using the OIE complement fixation test, the tissues of two horses were analysed by PCR. While PCR systems targeting the Burkholderia pseudomallei complex gave positive signals, the species-specific PCR systems targeting B. mallei (fliP-IS407A) and B. pseudomallei (orf11)-the OIE recommended targets-resulted in negative signals. However, the presence of B. mallei in these tissues was confirmed with a recently described B. mallei-specific real-time PCR system and genot...
Jorge RS, Ferreira F, Ferreira Neto JS, Vasconcellos Sde A, Lima Ede S, Morais ZM, Souza GO.Leptospirosis is a zoonotic disease affecting most mammals and is distributed throughout the world. Several species of domestic and wild animals may act as reservoirs for this disease. The purpose of this study was to assess the exposure of free-ranging wild carnivores, horses and domestic dogs on a private reserve located in the northern Pantanal (Brazil) and the surrounding areas to Leptospira spp from 2002-2006, 75 free-ranging wild carnivores were captured in the Pantanal and serum samples were collected. In addition, samples from 103 domestic dogs and 23 horses in the region were collecte...
Quan M, van Vuuren M, Howell PG, Groenewald D, Guthrie AJ.Between 2004 and 2006, 145 African horse sickness viruses (AHSV) were isolated from blood and organ samples submitted from South Africa to the Faculty of Veterinary Science, University of Pretoria. All nine serotypes were represented, with a range of 3-60 isolates per serotype. The RNA small segment 10 (S10) nucleotide sequences of these isolates were determined and the phylogeny investigated. AHSV, bluetongue virus (BTV) and equine encephalosis virus (EEV) all formed monophyletic groups and BTV was genetically closer to AHSV than EEV. This study confirmed the presence of three distinct S10 ph...
Ma J, Shi N, Jiang CG, Lin YZ, Wang XF, Wang S, Lv XL, Zhao LP, Shao YM, Kong XG, Zhou JH, Shen RX.To investigate essential factors that determine the efficacy of vaccines against lentiviruses, an effective attenuated equine infectious anemia virus (EIAV) vaccine strain and a proviral derivative of the vaccine were compared with respect to differences in inducing protective immunity. Although these two strains replicated equally well in vitro and in vivo, the proviral strain induced significantly less protection from disease and infection caused by viral challenge and significantly lower specific neutralizing capability. These findings indicated that the proviral strain had lost the ability...
Barbić L, Lojkić I, Stevanović V, Bedeković T, Starešina V, Lemo N, Lojkić M, Madić J.Equine herpesvirus type 1 (EHV-1) is a worldwide spread pathogen of horses. It can cause abortion, respiratory and neurological disease and consequentially significant economic losses in equine industries. During 2009, two outbreaks of EHV-1 were confirmed in two stud farms in Eastern Croatia. The first outbreak occurred in February following the import of 12 horses from USA, serologically negative to EHV-1 before transport. Four mares aborted in the late stage of pregnancy and one perinatal death was recorded. Other six mares showed clinical signs of myeloencephalopathy with fatal end in four...
Oikawa M, Takagi S, Anzai R, Yoshikawa H, Yoshikawa T.Eight young thoroughbred horses, taken 1858 km by road (travelling time, 41 h), were examined to assess the pathological nature of respiratory disease associated with transport. Three of the horses showed clinical abnormalities including pyrexia, coughing, leucocytosis and neutrophilia after the first 20 h of transportation. Endoscopical examination of the trachea revealed exacerbation of airway inflammation as a result of transport in two of the three affected horses. A consistent finding in the affected horses was focal serous neutrophilic pneumonia affecting the cranio-ventral portion of th...
Long MT, Jeter W, Hernandez J, Sellon DC, Gosche D, Gillis K, Bille E, Gibbs EP.The objectives of these studies were to assess the diagnostic performance (sensitivity and specificity) of the IgM capture enzyme-linked immunosorbent assay (ELISA; MAC) for diagnosis of West Nile (WN) virus in horses and to examine the performance of this test by using different criteria for seropositivity. A total of 36 horses classified as WN virus infected (group 1) and 383 horses from 4 subpopulations of hoses classified as noninfected (groups 2, 3, 4, and 5) were used in the study. The sensitivity (proportion of infected horses that tested positive for WN virus IgM antibodies) and specif...
Schoster A, Kunz T, Lauper M, Graubner C, Schmitt S, Weese JS.Overgrowth of enteric clostridia in dysbiosis in horses with colic is presumed but scarcely investigated. The objective was to provide prevalence data of Clostridium difficile and Clostridium perfringens in horses with and without gastrointestinal disease in Switzerland, and investigate microbiota differences between C. difficile shedders and non-shedders. Fecal samples were taken from healthy horses (n = 103), horses with colic (n = 98) and horses with diarrhea (n = 151). Colic horses were sampled on three days. Selective enrichment culture and molecular typing for C. difficile an...
López-Ruiz N, Montaño-Remacha MDC, Durán-Pla E, Pérez-Ruiz M, Navarro-Marí JM, Salamanca-Rivera C, Miranda B, Oyonarte-Gómez S....In Andalusia, Spain, West Nile virus (WNV) surveillance takes place from April to November, during the active vector period. Within this area seroconversion to this virus was evidenced in wild birds in 2004, affecting horses and two humans for the first time in 2010. Since 2010, the virus has been isolated every year in horses, and national and regional surveillance plans have been updated with the epidemiological changes found. WNV is spreading rapidly throughout southern Europe and has caused outbreaks in humans. Here we describe the second WNV outbreak in humans in Andalusia, with three con...
Maddox TW, Pinchbeck GL, Clegg PD, Wedley AL, Dawson S, Williams NJ.The increasing prevalence of antimicrobial resistant bacteria such as antimicrobial-resistant and extended spectrum β-lactamase (ESBL)-producing Escherichia coli represents a significant problem for human and veterinary medicine. Despite this, the risk factors for faecal carriage of such bacteria by horses in the UK, particularly those in the wider community, have not been well described. Objective: To characterise the risk factors for faecal carriage of antimicrobial-resistant E. coli amongst horses in the mainland UK. Methods: A cross-sectional study of horses recruited by 65 randomly selec...
Murphy TW, McCollum WH, Timoney PJ, Klingeborn BW, Hyllseth B, Golnik W, Erasmus B.Equine arteritis virus (EAV), a non-arthropod borne togavirus, has been shown to have a global distribution. To date, no major antigenic variation has been demonstrated between EAV isolates from different geographic origins. In this study, the genomic RNA of EAV isolates obtained from horses of different breeds in various countries around the world was oligonucleotide fingerprinted. Comparisons of these fingerprints were used to determine the extent of genomic variation among such isolates. Comparisons among isolates from North American horses revealed, for the most part, oligonucleotide homol...
Epp T, Waldner C, West K, Townsend H.In 2003, the occurrence and location of horses with clinical signs of West Nile virus infection were identified in the southern portion of Saskatchewan with the help of veterinarians, owners, and the regional laboratory. A total of 133 clinical cases were reported between July 30 and September 19, 2003; however, postseason surveillance suggests that the number of cases was underestimated. The case fatality rate was 43.8% (95% CI 35.2, 52.4). Factors associated with fatality in clinical cases included sex, week of onset of clinical signs, and coat color. Reported clinical cases clustered within...
Lu Z, Branscum AJ, Shuck KM, Zhang J, Dubovi EJ, Timoney PJ, Balasuriya UB.Two previously developed TaqMan fluorogenic probe-based 1-tube real-time reverse transcription polymerase chain reaction (real-time RT-PCR) assays (T1 and T2) were compared and validated for the detection of Equine arteritis virus (EAV) nucleic acid in equine semen and tissue culture fluid (TCF). The specificity and sensitivity of these 2 molecular-based assays were compared to traditional virus isolation (VI) in cell culture. The T1 real-time RT-PCR had a higher sensitivity (93.4%) than the T2 real-time RT-PCR (42.6%) for detection of EAV RNA in semen. However, the T1 real-time RT-PCR was les...
Pan L, Zhang L, Fan D, Zhang X, Liu H, Lu Q, Xu Q.Q fever is the most widespread zoonosis, and domestic animals are the most common sources of transmission. It is not only difficult to distinguish from other febrile diseases because of the lack of specific clinical manifestations in humans, but it is also difficult to identify the disease in C. burnetii-carrying animals because of the lack of identifiable features. Conventional serodiagnosis requires sera from the acute and convalescent stages of infection, which are unavailable at early diagnosis. Nested PCR and real-time PCR require equipment. In this study, we developed a Loop-Mediated Iso...
Gallusová M, Qablan MA, D'Amico G, Oborník M, Petrželková KJ, Mihalca AD, Modrý D.Rural areas of Romania, particularly the localities covering Danube Delta, are still not sufficiently explored in terms of epidemiological aspects, despite the large density of domestic animals living in close contact with people and natural environment of the Danube Delta Biosphere Reserve. Between 2010 and 2012, a survey on equine piroplasmids species was performed in this area, using a total of 178 horses, 15 donkeys and 177 dogs from 18 localities inside and outside the Danube Delta. None of the sampled hosts showed any clinical symptoms typical for equine piroplasmoses. A 25.4% overall pr...
Sweeney CR, Whitlock RH, Meirs DA, Whitehead SC, Barningham SO.Complications associated with Streptococcus equi infection developed in 15 (20.3%) of 74 horses on one farm included death, guttural pouch empyema, purpura hemorrhagica, upper respiratory tract obstruction, pneumonia, pleuropneumonia, agalactia, mesenteric lymph node abscessation, and periorbital abscessation. Death was attributed to pneumonia in 3 horses and to upper respiratory tract obstruction in 2 horses. One horse was euthanatized because of severe purpura hemorrhagica.
Manyweathers J, Field H, Jordan D, Longnecker N, Agho K, Smith C, Taylor M.Hendra virus was identified in horses and humans in 1994, in Queensland, Australia. Flying foxes are the natural host. Horses are thought to acquire infection by direct or indirect contact with infected flying fox urine. Humans are infected from close contact with infected horses. To reduce risk of infection in horses and humans, Australian horse owners are encouraged to vaccinate horses against the virus and adopt property risk mitigation practices that focus on reducing flying fox horse contact and contamination of horses' environment with flying fox bodily fluids. This study investigates up...
Holman PJ, Chieves L, Frerichs WM, Olson D, Wagner GG.Babesia equi was continuously cultured through 90 passages in an enriched chemically defined basal medium (HL-1) supplemented with 20% fetal bovine serum and serum replacement factors, including lipid-rich bovine serum albumin, bovine insulin, and human transferrin. Cryopreservation and subsequent recovery of B. equi were easily achieved. Inoculation of a splenectomized and an intact horse with cultured infected erythrocytes resulted in parasitemias and B. equi in vitro reisolation from both animals. In vitro forms of the parasite resembled in vivo forms. After establishment, parasitemias of 1...
Berlin D, Loeb E, Baneth G.Trypanosomiasis caused by Trypanosoma evansi ("Surra") is mainly a wasting disease affecting equids, camels and cattle as well as other domestic and wild animal species. In horses, infection may cause severe neurological abnormalities; however, the clinical progression, pathogenesis and molecular ante-mortem detection of this form of the disease have not been described in detail. A mare with progressive ataxia, head tilt, nystagmus and cranial nerve deficits submitted to treatment was diagnosed with central nervous system trypanosomiasis following the detection of a Trypanosoma tryposmastigote...
Dawson JE, Abeygunawardena I, Holland CJ, Buese MM, Ristic M.Eight adult cats were inoculated IV (n = 6) or SC (n = 2) with Ehrlichia risticii-infected P388D1 (continuous murine macrophage) cells or with E risticii released from P388D1 cells. Three additional cats were inoculated with organism-free P388D1 cultured monocytes, and 1 cat, which served as a medium control was inoculated with balanced salt solution. Clinical signs of illness were observed in the IV inoculated cats from which E risticii was isolated. One cat developed intermittent diarrhea between postinoculation days (PID) 8 and 18, and the other cat developed lymphadenopathy, acute depressi...
Ganzenberg S, Sieg M, Ziegler U, Pfeffer M, Vahlenkamp TW, Hörügel U, Groschup MH, Lohmann KL.West Nile virus (WNV) infections were first detected in Germany in 2018, but information about WNV seroprevalence in horses is limited. The study's overall goal was to gather information that would help veterinarians, horse owners, and veterinary-, and public health- authorities understand the spread of WNV in Germany and direct protective measures. For this purpose, WNV seroprevalence was determined in counties with and without previously registered WNV infections in horses, and risk factors for seropositivity were estimated. The cohort consisted of privately owned horses from nine counties i...
Rasche A, Lehmann F, Goldmann N, Nagel M, Moreira-Soto A, Nobach D, de Oliveira Carneiro I, Osterrieder N, Greenwood AD, Steinmann E, Lukashev AN....Preclinical testing of novel therapeutics for chronic hepatitis B (CHB) requires suitable animal models. Equids host homologs of hepatitis C virus (HCV). Because coinfections of hepatitis B virus (HBV) and HCV occur in humans, we screened 2,917 specimens from equids from five continents for HBV. We discovered a distinct HBV species (Equid HBV, EqHBV) in 3.2% of donkeys and zebras by PCR and antibodies against EqHBV in 5.4% of donkeys and zebras. Molecular, histopathological, and biochemical analyses revealed that infection patterns of EqHBV resembled those of HBV in humans, including hepatotro...
Sellon DC, Besser TE, Vivrette SL, McConnico RS.Recently, a technique was described for amplification of Rhodococcus equi-specific chromosomal and vapA DNA from blood and tracheal wash fluids. It was hypothesized that this technique would be more sensitive than standard culture techniques or serology for diagnosis of R. equi pneumonia in foals. Tracheal wash fluid, nasal swabs, whole blood samples, and serum samples from 56 foals with pneumonia were analyzed. Final clinical diagnosis was determined by the attending clinician on the basis of final interpretation of all available information about each foal, including clinical presentation, d...
Vieira RF, Vieira TS, Nascimento Ddo A, Martins TF, Krawczak FS, Labruna MB, Chandrashekar R, Marcondes M, Biondo AW, Vidotto O.The aims of this study were to determine the seroprevalence of Ehrlichia spp. and risk factors for exposure in a restricted population of dogs, horses, and humans highly exposed to tick bites in a Brazilian rural settlement using a commercial ELISA rapid test and two indirect immunofluorescent assays (IFA) with E. canis and E. chaffeensis crude antigens. Serum samples from 132 dogs, 16 horses and 100 humans were used. Fifty-six out of 132 (42.4%) dogs were seropositive for E. canis. Dogs > one year were more likely to be seropositive for E. canis than dogs ≤ one year (p = 0.0051). Ten/16 (62...
