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.
Darlington RW, James C.Darlington, R. W. (St. Jude Children's Research Hospital, Memphis, Tenn.), and C. James. Biological and morphological aspects of the growth of equine abortion virus. J. Bacteriol. 92:250-257. 1966.-The growth of equine abortion virus (EAV) was studied by bioassay and electron microscopy in L-cell monolayer and suspension cultures, and in HeLa and BHK 21/13 cell monolayers. Results of virus assay (plaque-forming units) indicated that production of cell-associated virus (CAV) began at 6 to 9 hr after infection in all of the cell strains used. Virus release occurred 1 to 2 hr later. By 15 to 20 h...
Sanada Y, Noda H, Nagahata H.The blastogenic response of lymphocytes from 16 newborn foals naturally infected with Rhodococcus equi was investigated, in order to evaluate the relationship between R. equi infection and depressed host response. Naturally infected foals showed evidence of R. equi infection at 5-6 weeks of age, as determined by clinical, haematological, bacteriological and serological methods. The blastogenic response of lymphocytes against phytohaemagglutinin was significantly depressed (stimulation index < 1.80; P < 0.01, P < 0.05) in R. equi-infected foals at 5-6 weeks of age compared with those o...
Casola C, Pot SA, Lavaud A, Voelter K.Corneal cross-linking should be considered as treatment option in Friesian horses with infectious keratitis and corneal dystrophy. Optical coherence tomography, giving information of corneal structure, can help for diagnosis and monitoring.
Spoormakers TJ, IJzer J, Sloet van Oldruitenborgh-Oosterbaan MM.A 22-year-old Dutch Warmblood mare was referred to Utrecht University with progressive left hind limb paresis and hyporeflexia. The preliminary clinical diagnosis was the neurological form of equine herpes virus (EHV-1) infection. Within 1 day of admission, the mare became recumbent and deteriorated rapidly. Postmortem examination revealed an adenocarcinoma of the caecum, with metastases in all regional lymph nodes and extending from the lumbar nodes into the vertebral canal, causing spinal cord compression and destruction of the left 4th and 5th lumbar nerves.
Schoster A, Anderson ME.A 9-year-old Quarter horse was presented for chronic refractory pneumonia. On necropsy, an hepatic abscess, caudal vena cava thrombosis, pulmonary thromboembolism, and embolic pneumonia were identified. Similar lesions have been reported in cattle as caudal vena cava thrombosis syndrome, however this syndrome has not previously been reported in horses. Un cheval Quarter horse âgé de 9 ans est présenté pour une pneumonie réfractaire chronique. À la nécropsie, un abcès hépatique, une thrombose de la veine cave caudale, un thromboembolisme pulmonaire et une pneumonie embolique ont été...
Oge S, Oge H, Yildirim A, Kircali F.Necropsies on 43 horses, 35 donkeys and two mules slaughtered in Ankara, Turkey, revealed that 12 (15%) of the equines harboured adult Setaria equina. When blood samples were checked for microfilariae, using Knott's method and a combination of membrane filtration followed by histochemical staining for acid phosphatase (AP), only three (4%) of the animals were found to be microfilaraemic. When stained for AP, the S. equina microfilariae exhibited diffuse red staining over the entire body, including the sheath, with brighter staining around the anal and excretory pores. Application of Knott's me...
West Nile virus in Europe and the USA. Evidence that the spread of vesicular stomatitis in the USA is beginning to slow. Summary of UK surveillance testing, July to September 2015 These are among matters discussed in the most recent quarterly equine disease surveillance report, prepared by Defra, the Animal Health Trust and the British Equine Veterinary Association.
Weiblen R, Rabuske M, Rebelatto MC, Nobre VM, Canabarro TF.We report an outbreak of abortion due to equine herpesvirus (EHV) in 5 mares between 9 and 11 months of gestation, from a herd of 22 Thoroughbred mares. Equine herpesvirus was isolated from extracts of the liver, spleen and thymus but not from the lungs of a 9-month fetus grown in Rabbit Kidney (RK13) cells. The virus was identified by electron microscopy, where virus particles could be seen in the nucleus of infected cells, and by the fluorescent antibody technique with polyclonal antibodies against the whole virus. Anamnesis, necropsy, histopathology, bacteriology, and virology data suggest ...
Metz GE, Serena MS, Ocampos GM, Panei CJ, Fernandez VL, Echeverría MG.Equine arteritis virus (EAV) was isolated from a testicle of the presumable first stallion infected with EAV in Argentina. This virus isolate (named LT-LP-ARG) was confirmed by GP5-specific PCR and indirect immunofluorescence assays. The PCR product was sequenced, and the phylogenetic analysis revealed that the LT-LP-ARG strain of EAV forms a monophyletic group, together with other strains previously isolated in our laboratory (LP02 group). However, all Argentinean EAV strains belong to a polyphyletic group. We believe that the virus isolate presented in this report could be the origin of EAV ...
Menassé I.After a brief reference to the importance of the non-parenteral route of vaccination of domestic animals in general, the author deals, for each animal species separately, with the most important vaccines utilised by this method of administration. On the basis of bibliographical data, he describes the history of this use, discusses the results of the application in the field and draws the relative conclusions.
Paskin R.The equine influenza outbreak detected in August 2007 in New South Wales and Queensland did not enter Victoria, which was, however, considered at risk because of its sizable border with New South Wales. Accordingly, Victoria implemented a response plan to prevent disease entry and enable early detection of any disease. Horse movement restrictions, surveillance strategies and public awareness formed a large part of this response.
Lopes CA, Moreno G, Curi PR.The susceptibilities of 760 Staphylococcus aureus strains isolated from animal infections (400), human infections (300) and healthy human carriers (60) to seven antibiotics were determined by an agar dilution technique. The isolates from human infections were more resistant to a wider spectrum of antibiotics than were the strains from animal infections and healthy human carriers. Amikacin and gentamicin were the most active drugs against all groups of strains.
Johnson AD, Eddy GA, Gangemi JD, Ramsburg HH, Metzger JF.Primary cell cultures, a continuous cell line, and a diploid cell line were grown on an artificial capillary system. The cells were subsequently infected with Venezuelan equine encephalitis virus, and viral replication was studied. Extracellular fluids harvested from this system contained high titers of virus and were relatively free of cell debris.
Vanderstraeten E, Bogaert L, Bravo IG, Martens A.Squamous cell carcinoma (SCC) represents the most common malignant tumour of the eye and external genitals in horses. Comparable to humans, papillomaviruses (PV) have been proposed as etiological agents of cancer in horses and recently, Equine papillomavirus type 2 (EcPV2) has been identified in genital SCCs. Hitherto it had never been demonstrated in ocular SCCs. The first goal of this study was to determine the prevalence of EcPV2 DNA in tissue samples from equine genital and ocular SCCs, genital papillomas and penile intraepithelial neoplasia (PIN) lesions, using EcPV2-specific PCR. The sec...
Sutcliffe IC, Trigg J, Harrington D.Using preparative electrophoresis, a low molecular weight protein has been partially purified from a cell extract of the equine pathogen Streptococcus equi susp. equi. N-terminal sequence analysis and Western blotting revealed the protein to be HPr, a central component of the phosphoenolpyruvate:sugar phosphotransferase system (PTS). Interestingly, the only form of the HPr protein detected in S. equi was one with the amino-terminal methionine removed, a modification that has previously been associated with surface localization of streptococcal HPr proteins.
Eckert J.Selected ectoparasitoses of animals are reviewed with special reference to the situation in Switzerland. The review contains information on the parasitoses leishmaniasis of dogs, parafilariasis of equines and cattle, onchocercosis of cattle and horses, ixodiosis, demodicosis of dogs and scabies of domestic animals, fly infestation, myiasis, and infestation with fleas and black flies (simuliidiosis). In addition to information on prevalence, biology and pathogenic effects of ectoparasites, the review provides indications on diagnosis and control.
West Nile virus in Europe and the USA. Evidence that the spread of vesicular stomatitis in the USA is beginning to slow. Summary of UK surveillance testing, July to September 2015 These are among matters discussed in the most recent quarterly equine disease surveillance report, prepared by Defra, the Animal Health Trust and the British Equine Veterinary Association.
Richards KS, Ilderton E, Yardley HJ.Lipids extracted from the laminated layers of horse liver and lung hydatids, including a daughter liver cyst, were analysed using TLC. No differences in lipid composition was detected in 11 liver cysts, whether from the same or different livers, and di- and triacylglycerols, cholesterol, wax and steryl esters, oleic acid, sphingomyelin, phosphatidyl choline, phosphatidyl inositol and ceramide hexosides were detected. The daughter cyst differed from its "parent" cyst in lacking diacylglycerols and wax and steryl esters. The lung cyst differed from the liver cysts in that cholesterol, wax and st...
Karamendin K, Abishov A, Kydyrmanov A, Akhmetzhanova M.In 2011, there was an outbreak of a disease with mass abortions among horses in southeastern Kazakhstan. The AK-2011 strain was isolated from an aborted fetus and subsequently identified as equid alphaherpesvirus 1. Here, we describe the nearly complete genome sequence of the AK-2011 strain, attenuated for vaccine development.
Kornilova OA.Endobiotic ciliates of native Yakut horse are investigated. 57 ciliate species have been found. From 17 up to 43 species of ciliates have been revealed in each host specimen. The specimens of Alloiozona trizona Hsiung, 1930 and Triadinium caudatum Fiorentini, 1890 were present in 100 % of the horses. The endemic genus and species of allantosomides, Strelkowella urunbasiensis Kornilova, 2004, has been found in 11 horses. Allantoxena japonensis (Imai, 1979) and Cycloposthium ishikawai Gassovsky, 1919 being recorded previously in Japan only were found for the first time in Russia. The species Cyc...
Paulino PG, Almosny N, Oliveira R, Viscardi V, Müller A, Guimarães A, Baldani C, da Silva C, Peckle M, Massard C, Santos H.An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Nemoto M, Okita N, Kitahata M, Bannai H, Tsujimura K, Kinoshita Y, Kambayashi Y, Cullinane A, Yamanaka T, Ohta M.A rapid and sensitive diagnostic method is needed to help prevent the spread of equine influenza virus. The cobas Influenza A/B & RSV test for the cobas Liat system (Roche Diagnostics) is based on real-time reverse transcription polymerase chain reaction and is designed to broadly detect influenza A virus RNA within 20 minutes. It detected a broad range of equine influenza virus strains, and detected equine influenza virus RNA from nasal swabs of infected horses at the same level as real-time reverse transcription polymerase chain reaction, although it returned some invalid results (7.7%)...
Kydd J, Nielsen M, Waller A.Julia Kydd, Martin Nielsen and Andrew Waller highlight some of the key presentations given at last year's 11th International Equine Infectious Diseases Conference, which was held virtually.
Morsy AT, Saleh MS, Morsy TA.A zoonosis is an animal disease that is transmissible to humans. Humans are usually an accidental host that acquires disease through close contact with an infected animal, who may or may not be symptomatic. Children are at highest risk for infection because they are more likely to have close contact with pets. Pets are responsible for transmission of an extensive array of bacterial, fungal, and parasitic zoonotic pathogens. The route of transmission can be through the saliva (e.g., bites or contaminated scratches), feces, respiratory secretions, direct contact, or by the animal acting as a veh...
Costa PWL, Oliveira CSM, Bezerra RA, Alvares FBV, Formiga VHAS, Martins MRDD, Feitosa TF, Vilela VLR.The aim of this study was to describe the prevalence of anti- and anti- antibodies in equids that carry out traction work in Northeastern Brazil, and to establish the potential risk factors associated with seropositivity for these agents. Blood samples were collected from 322 traction equids (horses, donkeys and mules) in urban areas of 16 municipalities in the State of Paraíba, Brazil. The samples were sent for serological diagnosis using the Immunofluorescence Antibody Test (IFAT). Epidemiological questionnaires were given to the owners to assess the possible risk factors associated with in...
Flanders JA, Wack RF, Pusterla N, Mapes SM, Collins D, Gamble KC.Infection by equine herpesvirus (EHV) strains (EHV-1, EHV-9) in ursid species, including polar bears ( Ursus maritimus), has been associated with neurological disease and death. A serosurvey of captive exotic equid and polar bear populations in US Association of Zoos and Aquaria institutions was performed to determine the prevalence of EHV strains using quantitative polymerase chain reaction (qPCR) and enzyme-linked immunosorbent assay (ELISA) tests. Equid species surveyed included zebra ( Equus spp.), Przewalski's wild horse ( Equus ferus przewalskii), Persian onager ( Equus hemionus), and So...
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.
Takizawa T, Ito T.Supposing two mathematical models, additive and multiplicative, the authors estimated the secular trends of annual morbidities (1949 approximately 1975) of twelve infectious diseases of domestic animals. For each diseases ten different trend curves were fitted. It was found that five regression equations, namely, those for bovine trichomoniasis, bovine tuberculosis, equine infectious anemia, pullorum disease in chickens, and foulbrood, gave the coefficient of determination of 97.9, 92.7, 91.0, 93.5, and 85.2%, respectively. Four of them were multiplicative, and the remaining one for equine inf...
Rejnö S.Synovial fluid samples from 51 light horses were examined with respect to their rhéologie properties. The analyses were made with a Rotovisco RV3 rotational viscosimeter. Samples from carpal, stifle and hock joints and from healthy joints, joints with synovitis and joints with infectious arthritis were studied. The analyses showed that synovial fluids from both healthy and diseased joints have complex rhéologie properties. In most samples the viscosity varied with the shear rates, the main exceptions being synovial fluids from joints with infectious arthritis. Flow curves (flow behaviour), r...
Pozio E, Tamburrini A, Sacchi L, Gomez Morales MA, Corona S, Goffredo E, La Rosa G.Routine examination for Trichinella infection by artificial digestion of 5-g samples of muscle tissue revealed the presence of muscle larvae in one out of 28 horses imported from Romania to an abattoir in Italy. The parasite, identified as Trichinella spiralis by the polymerase chain reaction, showed a reproductive capacity index of 68 in Swiss mice. Light microscope examination of 200 nurse cell-larva complexes showed that 22% of them were calcified and that the capsules of the non-calcified nurse cells were 17.5-27.5 microns (s = 22.67 microns) thick and had very few cellular infiltrates. Th...
Tivey ML.Mary-Ellen Lloyd Tivey of the Royal Veterinary College, suggests that greater collaboration and encouraging engagement from horse owners and vets is key to strengthening scanning surveillance in equine populations.
