The study of viral infections that affect equine species assesses the relationship between viruses and horses. Infections can lead to a range of clinical symptoms and may impact the health and performance of horses. Common equine viruses include Equine Influenza Virus, Equine Herpesvirus, and West Nile Virus, among others. Understanding the mechanisms of viral transmission, pathogenesis, and host immune responses is essential for developing effective prevention and treatment strategies. This page compiles peer-reviewed research studies and scholarly articles that explore the epidemiology, molecular biology, and clinical management of viral infections in horses.
Littler E, Yeo J, Killington RA, Purifoy DJ, Powell KL.Previously, we have shown a common antigen of several herpesviruses (pseudorabies virus, equine abortion virus and bovine mammillitis virus) to be antigenically related to the major DNA-binding proteins of herpes simplex virus types 1 and 2. In this study we have purified the cross-reacting polypeptide from cells infected with pseudorabies virus, equine abortion virus and bovine mammillitis virus and shown the cross-reacting protein to be a major DNA-binding protein for each virus. Tryptic peptide analysis of the cross-reacting DNA-binding proteins of all five viruses has shown structural simi...
Salama SA, Dardiri AH, Awad FI, Soliman AM, Amin MM.African horsesickness virus was isolated from blood samples of street dogs in Aswan Province in Arab Republic of Egypt. Of six isolated "dog strain" African horsesickness viruses, three viruses designated D2, D6 and D10 have been identified as type 9 African horsesickness virus. Methods of isolation, tissue culture adaptation, serological indentification and typing are described. Horses experimentally infected with dog viruses showed febrile reaction and characteristic clinical and pathological signs of African horsesickness. Reisolation of African horsesickness virus type 9 was achieved from ...
Thein P.During the last 2 years different equine herpesviruses serotype 1 strains have been isolated from cases of paretic or paralytic disease among horses in the Federal Republic of Germany. In this paper the available information is collated and briefly reviewed. A short description of the symptoms and the possible mechanism of the pathogenesis are given.
Bochkova NG, Koreshkova GV, Pogodina VV.A total of 5227 serum specimens from humans, horses and swine collected in the seasons of 1968--1976 in 15 administrative areas of the Primorskiy Kray were examined with antigens of a number of mosquito-borne arboviruses: Japanese encephalitis (JE), West Nile (WN), Getah, and Sindbis. Both independent and combined circulation of these viruses in the region was established. Sindbis virus was found to be circulating separately most frequently, West Nile virus the least frequently. According to the results of the serological analysis, the conditions for combined circulation are most closely relat...
Williams DL, Issel CJ, Steelman CD, Adams WV, Benton CV.Biological and mechanical transmission trials with Psorophora columbiae (Dyar and Knab) and Aedes sollicitans (Walker) and ponies acutely infected with equine infectious anemia virus (EIAV) were negative. The EIAV antigen was detected by radioimmunoassay in Ae sollicitans immediately after the mosquitoes had fed on an acutely ill pony, but not 14 days after feeding. Psorophora columbiae mosquitoes had detectable EIAV antigen as determined by radioimmunoassay 24 hours after they fed on an acutely ill pony; this antigen was not detected again until 6 days after feeding and was still detected 14 ...
Harry TO, McCollum WH.The Bucyrus strain of equine arteritis virus, previously modified to avirulence and vaccinal virus by 131 serial passages in primary cell cultures of horse kidney followed by 111 passages in primary cell cultures of rabbit kidney, was further passaged in cultures of the E. Derm (NBL-6) cell line, a continuous diploid cell line. Pools of the 16th and 25th passages of the virus in this last equine dermal cell line were lyophilized and stored in lots at 37 C, 23 to 28 C, 4C, and -20 C. The viability of the vaccinal virus deteriorated rapidly during storage at 37 C and at 23 to 28 C, but was relat...
Monath TP, McLean RG, Cropp CB, Parham GL, Lazuick JS, Calisher CH.Brain tissues were obtained from 5 horses with clinical encephalomyelitis during an epizootic in southwestern Michigan in August-September 1980. These tissues were tested for virus by intracerebral inoculation of suckling mice and by examination of frozen sections and impression smears by the indirect fluorescent antibody (FA) technique. Eastern equine encephalomyelitis virus was isolated and detected by FA technique in brains of 3 horses which died or were euthanatized within approximately 24 hours of onset of the disease but not from 2 horses at 2 and 3 days after onset. The latter 2 animals...
McCollum WH.Twenty horses that were seronegative for equine arteritis virus antibodies were inoculated IM with live equine arteritis virus vaccine. The inoculation did not cause clinical signs of disease. A mild, transient febrile reaction developed in 6 horses, 3 of which were in poor condition before inoculation. Six horses, 2 of which were in poor condition before inoculation, experienced mild lymphopenia. Necropsy revealed mild lesions in the lymph nodes of 6 horses (3 of which were in poor condition before inoculation). Maximum concentrations of virus were detected in the lymph nodes and were consist...
Scherer WF, Cupp EW, Lok JB, Brenner RJ, Ordonez JV.The minimal intestinal dose of an enzootic strain of Venezuelan encephalitis (VE) virus for Culex (Melanoconion) taeniopus mosquitoes caught at a marsh habitat of VE virus in Guatemala was less than five plaque forming units (pfu) of virus. Ingestion of this dose of virus in blood of viremic hamsters resulted in transmission of virus to other hamsters. This low intestinal threshold of an enzootic strain of VE virus indicates that the natural Guatemalan population of Cu. (Mel.) taeniopus can acquire VE virus from vertebrates that have viremia levels as low as 1,000-5,000 pfu/ml of blood, provid...
Justines G, Oro G, Alvarez O.The P-676 and MF-8 epizootic strains of Venezuelan equine encephalitis (VEE) virus were found to contain a minute plaque (MP), different from the predominant small plaque (SP) present in these virus strains. The MP and SP were stable after passages in Vero cells, mice, or horses. Equines were inoculated with the SP or MP of the P-676 and MF-8 strains. Inoculation of either P-676 SP or MP into horses induced high fever and viremia but no signs of encephalitis or death. Four horses infected with MF-8 SP became very ill, with high fever and viremia; three of the inoculated animals died. Four hors...
Snyder DB, Myrup AC, Dutta SK.Pony foals, negative for detectable serum-neutralizing antibody to equine herpesvirus 1 by the standard tube-culture virus neutralization test, were experimentally infected with equine herpesvirus 1. Complement-requiring (CR) and non-complement-requiring (NCR) serum-neutralizing antibodies were evaluated in preinfection and postinfection sera by means of a complement-enhanced plaque reduction assay. Low levels of CR antibodies were found in the preinfection sera of only group II ponies. Upon infection, CR antibodies were detected by day 2 postinfection and reached peak titers between 7 and 14 ...
Grădinaru DA, Stirbu C, Păltineanu D, Mironescu D, Manolescu N.The Wyoming strain of equine infectious anemia virus was adapted to cell cultures by 7 passages in horse leukocytes and 14 passages in fetal equine dermal and kidney cells. The virus was made evident by electron microscopy and immunodiffusion tests with antigens prepared from culture fluids.
Sentsui H, Kono Y.Six strains of equine infectious anemia (EIA) virus propagated in equine leukocyte cultures were found to agglutinate horse erythrocytes. Concentrated virus material containing about 20 units of complement fixation (CF) titer showed hemagglutinating (HA) titers ranging from 4 to 8 units. The HA activity remained stable after ether treatment and was reduced by trypsin, formaldehyde and KIO4. Cesium chloride equilibrium density gradient centrifugation revealed two populations of hemagglutinin, one in the density range of 1.15-1.16 g/ml coinciding with a peak of CF antigen and the other at round ...
Benton CV, Brown BL, Harshman JS, Gilden RV.Equine infectious anemia virus (EIAV) was successfully inoculated onto cell cultures of canine and feline origin, resulting in chronic infections in these cultures. Infection of equine cell cultures, which were the previous sole in vitro source demonstrated for virus production, was also performed for comparative purposes. Determination of the nature of the virus produced in the heterologous as well as the equine cells was accomplished in several ways. SDS-PAGE of purified virus from the different cell lines indicated very similar protein composition. Immunological identity was observed in gel...
Dutta SK, Myrup A, Bumgardner MK.Six pony foals, experimentally infected with equine herpesvirus 1 (EHV-1), were studied for their lymphocyte responses to EHV-1 and phytohemagglutinin (PHA) stimulations. Lymphocyte blastic transformation in the presence of EHV-1 appeared as early as 2 days after the foals were inoculated, reached a peak in 7 to 10 days, and subsequently decreased. In contrast, the lymphocyte blastic transformation in the presence of PHA increased sharply, reaching a peak in 2 to 3 days, and then decreased to its lowest level in 10 days after which it returned to its near preinoculation level. As for the mecha...
Bryans JT.Two herpesviruses produce diseases that affect reproductive efficiency in the horse. Equine herpesvirus 1 (EHV-1, equine rhinopneumonitis virus) is a promeinent cause of abortigenic infection as well as respiratory disease. Equine herpesvirus 3 (EHV-3, equine coital exanthema) is the cause of a benign progenital exanthema.
Ghanem YM, Ibrahim el-SM, Yamada S, Matsumura T, Osterrieder N, Yamaguchi T, Fukushi H.The pathogenicities of RacL11 and Kentucky D strains of equine herpesvirus 1 in the hamster infection model are different from those of Ab4p and the Japanese isolates. Virus genome restriction fragment length polymorphism analysis and sequence comparison of an intergenic region, glycoproteins and tegument genes showed higher conservation but with some strain-specific differences. These results indicate that point nucleotide differences in RacL11 and Kentucky D might be responsible for their pathogenicity in rodent models.
Ochi A, Bannai H, Aonuma H, Kanuka H, Uchida-Fujii E, Kinoshita Y, Ohta M, Kambayashi Y, Tsujimura K, Ueno T, Nemoto M.Mosquitoes and EDTA-treated blood samples from febrile racehorses were investigated for Getah virus infection from 2016 to 2019 at the Miho Training Center, where several outbreaks of Getah virus have occurred. We collected 5557 mosquitoes and 331 blood samples from febrile horses in this study. The most frequently captured mosquito species was Culex tritaeniorhynchus (51.9%), followed by Aedes vexans nipponii (14.2%) and Anopheles sinensis (11.2%). Getah virus was detected in mosquitoes (Aedes vexans nipponii) in 2016 (strain 16-0810-26) but not in 2017-2019. Six of 74 febrile horses in 2016 ...
Chen J, Guo X, Li L.The nucleocapsid (N) protein is the most conserved structural protein in equine arteritis virus (EAV). This study aimed to identify the minimal conserved B cell epitope on the EAV N protein. The purified N protein was used to immunize mice for preparing monoclonal antibody (mAb). The reactivity of mAb was evaluated by Western blot and immunofluorescence assay. Moreover, 11 overlapping peptides (named MBP-N1 to MBP-N11) were designed to localize the linear antigenic epitope within the N protein. The peptides were identified by indirect enzyme-linked immunosorbent assay (ELISA) and Western blot....
Gross DK, Morley PS, Hinchcliff KW, Reichle JK, Slemons RD.The purpose of this investigation was to determine if naturally occurring acute infectious upper respiratory disease (IRD) caused by equine influenza virus is associated with ultrasonographically detectable pleural and pulmonary abnormalities in horses. Standardbred racehorses were evaluated for signs of IRD, defined as acute coughing or mucopurulent nasal discharge. For every horse with IRD (n = 16), 1 or 2 horses with no signs of IRD and the same owner or trainer (n = 30) were included. Thoracic ultrasonography was performed within 5-10 days of the onset of clinical disease in horses with IR...
Sentsui H, Wu D, Murakami K, Kondo T, Matsumura T.Recombinant equine interferon-gamma (reIFN-gamma) was prepared using a baculovirus expression system and its antiviral activity was investigated using several equine viruses. The reIFN-gamma suppressed the replication of all equine viruses used in the present experiment in horse cell cultures, but did not affect the growth of host cells at concentrations of less than 1000 u/ml. A strong antiviral effect was observed, especially against RNA viruses. Equine picornavirus, equine rhinovirus and equine arteritis virus could not be propagated at all in 100 u/ml reIFN-gamma when 100 TCID(50) of infec...
Easther R, Manthorpe E, Woolford L, Kawarizadeh A, Hemmatzadeh F, Ferlini Agne G.Equine idiopathic haemorrhagic cystitis (EIHC) is a recently described form of aseptic cystitis in horses in which there is no discernible underlying cause. This case report describes a 9-year-old Thoroughbred gelding that presented with stranguria, pollakiuria, and haematuria. Cystoscopy revealed ulceration and haemorrhage of the bladder mucosa, diffuse mural hyperaemia and marked urine sedimentation. Histopathological evaluation of the bladder revealed chronic active ulcerative neutrophilic, lymphoplasmacytic, and eosinophilic cystitis. There was no bacterial or fungal growth upon culture bu...
Lopez KM, Fleming GJ, Mylniczenko ND.Reports of equine herpesvirus (EHV) 1 and EHV-9 causing clinical disease in a wide range of species have been well documented in the literature. It is thought that zebras are the natural hosts of EHV-9 both in the wild and in captive collections. Concerns about potential interspecies transmission of EHV-1 and EHV-9 in a mixed species savannah exhibit prompted serologic and polymerase chain reaction surveys. Eighteen Burchell's zebras ( Equus quagga ), 11 Hartmann's mountain zebras ( Equus zebra hartmannae), and 14 Thomson's gazelles ( Eudorcas thomsonii ) cohabitating the same exhibit were exa...
Bannai H, Nemoto M, Tsujimura K, Yamanaka T, Kondo T, Matsumura T.Non-specific hemolysis has often been observed during complement-fixation (CF) tests for equine herpesvirus type-1 (EHV-1), even when the sera have virus-specific CF antibodies. This phenomenon has also been reported in CF tests for various infectious diseases of swine. We found that the sera from 22 of 85 field horses (25.9%) showed non-specific hemolysis during conventional CF testing for EHV-1. Because pretreatment of swine sera with potassium periodate (KIO4) improves the CF test for swine influenza, we applied this method to horse sera. As we expected, horse sera treated with KIO4 did not...
Ramsay JD, Evanoff R, Mealey RH.Hepacivirus A (also known as nonprimate hepacivirus and equine hepacivirus) is a hepatotropic virus that can cause both transient and persistent infections in horses. The evolution of intrahost viral populations (quasispecies) has not been studied in detail for hepacivirus A, and its roles in immune evasion and persistence are unknown. To address these knowledge gaps, we first evaluated the envelope gene (E1 and E2) diversity of two different hepacivirus A strains (WSU and CU) in longitudinal blood samples from experimentally infected adult horses, juvenile horses (foals), and foals with sever...
Downs JA, Hyzer G, Marion E, Smith ZJ, Kelen PV, Unnasch TR.Eastern equine encephalitis (EEE) is a mosquito-borne viral disease that is often fatal to humans and horses. Some species including white-tailed deer and passerine birds can survive infection with the EEE virus (EEEV) and develop antibodies that can be detected using laboratory techniques. In this way, collected serum samples from free ranging white-tailed deer can be used to monitor the presence of the virus in ecosystems. This study developed and tested a risk index model designed to predict EEEV activity in white-tailed deer in a three-county area of Michigan. The model evaluates EEEV risk...
Surma-Kurusiewicz K, Winiarczyk S, Adaszek Ł.The purpose of this study was to conduct a comparative analysis of the ORF5 gene fragment nucleotide sequences and the GP5 protein amino acid sequences formed on this matrix, for the equine arteritis virus (EAV) strains isolated from the semen of infected stallions from Eastern Poland. The study covered 41 stallions whose blood serum tested positive for antigens specific to the EAV. The presence of EAV genetic material was shown in material from 5 horses, in one of which permanent presence of viral RNA was detected over the entire 4-year study period (the material was sampled four times at yea...
Smith IM, Girard A, Corner AH, Mitchell D.Using two known positive equine viral rhinopneumonitis (EVR) sera, conjugates were prepared with fluorescein isothiocyanate and tested for specificity using EVR infected tissue culture cells. The conjugate was then applied to selected tissues from 32 aborted fetuses and foals submitted during a natural outbreak of EVR. Antigen was detected in various tissues by immunofluorescence in 20 cases (62.5%). In 24 cases bovine fetal kidney cell monolayers were inoculated with a pool of lung and liver and EVR virus was isolated from 15 (62.5%). Histological examination of various tissues from 29 cases ...
Docherty DE, Samuel MD, Egstad KF, Griffin KM, Nolden CA, Karwal L, Ip HS.After the 2001 occurrence of West Nile virus (WNV) in Wisconsin (WI), we collected sera, during 2003-2006, from south-central WI mesopredators. We tested these sera to determine WNV antibody prevalence and geometric mean antibody titer (GMAT). Four-fold higher antibody prevalence and 2-fold higher GMAT in 2003-2004 indicated greater exposure of mesopredators to WNV during the apparent epizootic phase. The period 2005-2006 was likely the enzootic phase because WNV antibody prevalence fell to a level similar to other flaviviruses. Our results suggest that, in mesopredators, vector-borne transmis...
Dauphin G, Zientara S.West Nile virus, a flavivirus transmitted by mosquitoes, has been intensively studied since a few years because of epidemics/epizootics it has caused the last ten years, in particular around the Mediterranean basin and on the North-American continent. This virus mainly circulates in birds ; migrating bird species disseminate the virus while resident species could play a role in viral cycle amplification. A large number of mammal, amphibian and reptile species can also be infected. This virus can cause a lethal disease in humans and horses. For this reason, an active and/or passive surveillance...
Ma J, Zhang Z, Yao Q, Su C, Yin X, Wang X.Rev, an important accessory protein of equine infectious anaemia virus (EIAV), induces the nuclear export of incompletely spliced viral mRNAs. Rev is translated from the tat-rev mRNA through leaky scanning of the tat CUG. In this study, the function of the Kozak sequence at the beginning of the rev ORF was investigated. Deletion or attenuation of the Kozak sequence resulted in expression of an N-terminal 11 aa-truncated Rev in addition to WT Rev. Truncated Rev displayed weaker promotion of Gag expression and processing than WT Rev. Furthermore, EIAV rescued from an infectious molecular clon...
Naranjo Cerrillo G, Soler Rodríguez F, Gómez Gordo L, Hermoso de Mendoza Salcedo M, Roncero Cordero V.In 1988 an outbreak of leukoencephalomalacia was diagnosed in equids that had eaten corn with a pinkish fungal growth. The fungus was then identified as Fusarium moniliforme. The main symptoms observed appeared acutely and were overexcitement, blindness, incoordination, facial paralysis and death within 24 h. The main pathological changes were restricted to the central nervous system. Macroscopically they consisted of hyperemia and haemorrhages, the consistency was friable and the gyri were somewhat flattened. Microscopically, the lesions were profuse and had extensive haemorrhages, and numero...
Black JB, Frampton AR.Equine herpesvirus type 1 (EHV-1) is a highly transmissible pathogen that leads to a variety of clinical disease outcomes in infected horses. A major sequela that can occur after an EHV-1 infection is a neurological disease termed equine herpesvirus myeloencephalopathy (EHM). Clinical manifestations of EHM include fever, ataxia, incontinence, and partial to full paralysis, which may ultimately lead to the euthanization of the infected horse. To develop an effective treatment strategy for EHM, it is critical that the specific virus-host interactions that lead to EHM be investigated so that safe...
Montelaro RC, West M, Ivey M.Representative glycoproteins including fetuin, protein A, ovalbumin, alpha 1 acid glycoprotein, and the major glycoprotein of equine infectious anemia virus were labelled with 125I by the chloramine-T or Bolton-Hunter procedure and their binding to immobilized Con A or lentil lectin compared to untreated samples of each glycoprotein. Glycoprotein modification was no greater than one substituted residue per protein molecule. Yet the radioiodinated glycoproteins typically displayed only 0-50% of the lectin binding observed with untreated samples. These results indicate that lectin glycoprotein b...
Wiebe ME, Scherer WF, Peick WJ.Ninety-four strains of Venezuelan encephalitis (VE) virus isolated from sentinel hamsters exposed in the Middle American countries of Mexico, Guatemala, Belize, and Honduras were examined for the presence of virions with marker characteristics of strains that cause large epidemics and equine epizootics. Thirty-four strains came from before and 60 strains came from after the Middle American epidemics and equine epizootics of 1966 and 1969-1972. Twenty-three virion clones that resembled epizootic strains by hydroxylapatite chromatography and Vero monkey kidney cell plaque size determinations wer...
Chung C, Wilson C, Timoney P, Adams E, Adams DS, Chung JS, Evermann JF, Shuck K, Lee SS, McGuire TC.Equine arteritis virus (EAV) causes contagious equine viral arteritis, characterized by fever, anorexia, conjunctivitis, nasal discharge, dependent edema, abortion, infrequent death in foals, and establishment of the carrier state in stallions. The World Organization for Animal Health (OIE) defines a horse as seropositive if the serum neutralization (SN) antibody titer is ≥1:4 to EAV. However, determining the SN titer is time-consuming and requires specific laboratory facilities, equipment, and technical expertise to perform. Furthermore, interpretation of the SN titer of some sera can be di...
Ahn B, Zhang Y, Osterrieder N, O'Callaghan DJ.The 150 kbp genome of equine herpesvirus-1 (EHV-1) is composed of a unique long (UL) region and a unique short (Us) segment, which is flanked by identical internal and terminal repeat (IR and TR) sequences of 12.7 kbp. We constructed an EHV-1 lacking the entire IR (vL11ΔIR) and showed that the IR is dispensable for EHV-1 replication but that the vL11ΔIR exhibits a smaller plaque size and delayed growth kinetics. Western blot analyses of cells infected with vL11ΔIR showed that the synthesis of viral proteins encoded by the immediate-early, early, and late genes was reduced at immediate-early...
Mason JB, Gurda BL, Van Wettere A, Engiles JB, Wilson JM, Richardson DW.Our long-term aim is to develop a gene therapy approach for the prevention of laminitis in the contralateral foot of horses with major musculoskeletal injuries and non-weightbearing lameness. Objective: The goal of this study was to develop a practical method to efficiently deliver therapeutic proteins deep within the equine foot. Methods: Randomised in vivo experiment. Methods: We used recombinant adeno-associated viral vectors (rAAVs) to deliver marker genes using regional limb perfusion through the palmar digital artery of the horse. Results: Vector serotypes rAAV2/1, 2/8 and 2/9 all succes...
Allen GP, Cohen JC, Randall CC, O'Callaghan DJ.The replication of equine herpesvirus type 1 (EHV-1) and type 3 (EHV-3) was unimpeded in three different cell types-equine epithelial cells, equine fibroblasts, and mouse fibroblasts-which had been blocked in their capacity to synthesize host DNA by 2.5 mM hydroxyurea (HU) or 2 mM thymidine (TdR). The rate of DNA synthesis in uninfected or equine herpesvirus-infected cells in the presence of HU or TdR was measured by pulse-labeling cell samples with a labeled DNA precursor at different times after infection. DNA synthesis in uninfected cultures was completely inhibited by both compounds. Howev...
Ryder E, Ryder S.Venezuelan equine encephalitis (VEE) virus has been implicated as producing alterations in glucose metabolism in animals. We performed oral glucose tolerance tests and measured serum immunoreactive insulin responses in 13 patients who were infected by VEE virus during an epidemic in 1969, in Zulia State, Venezuela. No significant alterations in the glucose tolerance test were found. Sera of 86 diabetic outpatients and 98 control individuals with normal glycemia at a local hospital were tested for antibodies to VEE virus by hemagglutination inhibition. No statistically significant difference wa...
Thomas RJ.An antigen for the gel diffusion test for equine infectious anaemia (EIA) was prepared from the spleen of a horse experimentally infected with the CQ strain of the virus. The antigen produced a single, distinct line of precipitation when tested against a range of known positive serums, and did not react with pre-inoculation and known negative serums. Extracts prepared from uninfected spleens displayed no reaction when similarly tested. Serum from 34 of 451 Queensland horses contained detectable levels of antibody to EIA virus. The positive serums were from horses in widely separated areas of t...
Diaz-Méndez A, Viel L, Shewen P, Nagy E.Equine rhinitis A virus (ERAV) is an ubiquitous virus, routinely identified in equine respiratory infections; however, its role in disease and genetic features are not well defined due to a lack of genomic characterization of the recovered isolates. Therefore, we sequenced the full-length genome of a Canadian ERAV (ERAV/ON/05) and compared it with other ERAV sequences currently available in GenBank. The ERAV/ON/05 genome is 7,839 nucleotides (nts) in length with a variable 5'UTR and a more conserved 3'UTR. When ERAV/ON/05 was compared to other reported ERAV isolates, an insertion of 13 nt in t...
Ochi A, Sekiguchi M, Tsujimura K, Kinoshita T, Ueno T, Katayama Y.Equine multinodular pulmonary fibrosis (EMPF) is a recently described form of interstitial pneumonia associated with equine herpesvirus type 5 (EHV-5). This disease has been reported in North and South America, Europe and Oceania but not, to our knowledge, in horses in Japan. We diagnosed EMPF in two Thoroughbred horses in Japan on the basis of gross and histopathological findings. In both cases, significant gross lesions, restricted to the lungs, consisted of numerous firm and coalescing nodules widely distributed throughout the lung. The nodules were <3 cm in diameter and pale white to t...
Onasanya AE, El-Hage C, Diaz-Méndez A, Vaz PK, Legione AR, Browning GF, Devlin JM, Hartley CA.Equid gammaherpesvirus 2 (EHV2) is a gammaherpesvirus with a widespread distribution in horse populations globally. Although its pathogenic significance can be unclear in most cases of infection, EHV2 infection can cause upper respiratory tract disease in foals. Co-infection of different strains of EHV2 in an individual horse is common. Small regions of the EHV2 genome have shown considerable genetic heterogeneity. This could suggest genomic recombination between different strains of EHV2, similar to the extensive recombination networks that have been demonstrated for some alphaherpesviruses. ...
Christley RM, Rose RJ, Hodgson DR, Reid SW, Evans S, Bailey C, Hodgson JL.A questionnaire was administered to members of the Australian Equine Veterinary Association to investigate their attitudes and behaviours regarding the cause, diagnosis and treatment of lower-respiratory-tract disease in racehorses. The most-important perceived risk factors related to the level of exposure and resistance to infectious agents, whereas factors associated with racing and climatic factors were lower ranked. By far the most-commonly implicated primary cause of disease was respiratory viruses. However, specific diagnostic tests (such as viral serology or virus isolation) were rarely...
Hu WG, Chau D, Wong C, Masri SA, Fulton RE, Nagata LP.The genes encoding envelope proteins E1 and E2 of western equine encephalitis virus (WEEV) were respectively cloned into a prokaryotic T7 RNA polymerase-regulated expression vector. The recombinant C-terminal 6xHis-tagged WEEV E1 and E2 were expressed in bacteria as inclusion bodies that were subsequently solubilized with 8M urea, purified by immobilized metal ion affinity chromatography and finally refolded using an arginine system. The purified 6xHis-tagged proteins showed 50kDa bands as revealed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis, consistent with the expected size...
