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.
Burrell MH, Wood JL, Whitwell KE, Chanter N, Mackintosh ME, Mumford JA.A longitudinal study of respiratory disease in racehorses was carried out to assess its relative associations with different infectious agents and to examine any role that the environmental conditions might play. The relationships between coughing, nasal discharge, pyrexia and lower respiratory tract disease were also examined to provide information for improving clinical diagnosis, particularly of disease of the lower respiratory tract. Lower airway disease was closely associated with infection with Streptococcus zooepidemicus. It was also found that equine herpesvirus seroconversions and S p...
Paweska JT, Aitchison H, Chirnside ED, Barnard BJ.Lateral and sexual transmission of EAV among horses and lateral transmission between donkeys and horses were attempted by experimental infection with the South African asinine strain. Clinical, immunological and virological responses were evaluated. All intramuscularly inoculated horses developed very mild clinical signs, were viraemic, shed virus from nasopharynx, and seroconverted. Lateral infection was demonstrated in one in-contact mare. Reinfection of two stallions by intranasal instillation was shown by virus recovery from buffy-coat cultures. After nasal instillation of virus, one stall...
Olaleye OD, Tomori O, Schmitz H.Between 1986 and 1989, 2,255 sera collected from six domestic animal species in Nigeria were tested for antibodies to Rift Valley fever (RVF) virus. In addition, a longitudinal study was carried out from July 1987 to December 1988, using ten sentinel flocks on four farms at Ibadan and Ile-Ife, to determine the activity of RVF virus (RVFV). All samples were tested for haemagglutination-inhibiting antibodies and positive sera were further screened, using the plaque reduction neutralisation test. Of 2,255 samples, 259 (11.5%) had haemagglutination-inhibiting and neutralising antibodies, as follow...
Glaser AL, de Vries AA, Rottier PJ, Horzinek MC, Colenbrander B.Sero-epidemiological surveys have revealed that equine arteritis virus (EAV) is prevalent in most European countries. The virus causes sporadic cases of respiratory disease and abortion in horses, the incidence of which has increased in recent years. Mares and geldings eliminate virus after acute infection, but 30% to 60% of stallions become persistently infected. In these animals, EAV is maintained within the reproductive tract and is shed continuously in the semen. Persistent infection with EAV in stallions has no negative consequences for fertility but mares inseminated with virus-contamina...
Weaver SC, Salas R, Rico-Hesse R, Ludwig GV, Oberste MS, Boshell J, Tesh RB.Venezuelan equine encephalomyelitis (VEE) virus has caused periodic epidemics among human beings and equines in Latin America from the 1920s to the early 1970s. The first major outbreak since 1973 occurred in Venezuela and Colombia during 1995, and involved an estimated 75,000 to 100,000 people. We report an epidemiological and virological investigation of this epidemic. Methods: Virus isolates were made in cell culture from human serum, human throat swabs, and brain tissue from aborted and stillborn human fetuses, as well as from horse brain tissue and pooled mosquito collections. Human sera ...
Wutz G, Auer H, Nowotny N, Grosse B, Skern T, Kuechler E.Equine rhinoviruses (ERVs) are picornaviruses which cause a mild respiratory infection in horses. The illness resembles the common cold brought about by rhinoviruses in humans; however, the presence of a viraemia during ERV-1 infection, the occurrence of persistent infections and the physical properties are all more reminiscent of foot-and-mouth disease virus (FMDV). cDNA cloning and sequencing of the genomes of ERV-1 and ERV-2 between the poly(C) and poly(A) tracts showed that the serotypes are heterogeneous. Nevertheless, the genomic architecture of both serotypes is most similar to that of ...
Gustchina A, Kervinen J, Powell DJ, Zdanov A, Kay J, Wlodawer A.Equine infectious anemia virus (EIAV), the causative agent of infectious anemia in horses, is a member of the lentiviral family. The virus-encoded proteinase (PR) processes viral polyproteins into functional molecules during replication and it also cleaves viral nucleocapsid protein during infection. The X-ray structure of a complex of the 154G mutant of EIAV PR with the inhibitor HBY-793 was solved at 1.8 A resolution and refined to a crystallographic R-factor of 0.136. The molecule is a dimer in which the monomers are related by a crystallographic twofold axis. Although both the enzyme and t...
Hyatt AD, Selleck PW.The ultrastructure of the equine morbillivirus (EMV) which was implicated in the death of one human and fourteen horses in Queensland, Australia during September 1994 and a 36 year old man from Queensland in October 1995 is described. The ultrastructure of the virus and the intracellular virus-specific structures are characteristic for the family Paramyxoviridae. Cytoplasmic nucleocapsids were observed within the infected cells monolayers, endothelial cells (lung) of infected horses and the neurons within the brain of the 36 year old Queensland man. Aggregates of smaller nucleocapsid-like stru...
Gould AR.The nucleotide sequence of the matrix protein of equine morbillivirus (EMV) was determined to be 1062 nucleotides and coded for a deduced protein of M(r) 40148 having a net charge of + 19 at neutral pH. The matrix protein gene was separated from the P and F genes by intercistronic regions of 546 and 469 nucleotides, respectively. The nucleotide sequence which coded for the F protein was 1641 nucleotides and coded for a deduced protein of 546 amino acids having an M(r) of 60,447 and a charge + 4 at neutral pH. Partial sequence information was also determined for the P/V proteins. M, P and F pro...
Ross WA, Kaneene JB.To evaluate outbreaks of disease attributable to eastern equine encephalitis virus (EEEV) in horses in Michigan, and the associated environmental patterns and weather conditions, so that factors could be identified that may have predisposed horses in specific areas of the state to infections with EEEV. Methods: Epidemiologic retrospective records analysis. Methods: Data on EEEV vectors, wild-bird reservoir hosts, and incidental hosts, including horses and human beings, obtained from census reports and medical records compiled between 1942 and 1991. Methods: Patterns detected during outbreaks o...
Stone-Marschat MA, Moss SR, Burrage TG, Barber ML, Roy P, Laegreid WW.Horses were immunized by inoculation with a vaccinia construct containing a full-length cDNA corresponding to the L2 gene segment of African horsesickness virus type 4(AHSV-4). All immunized horses developed serum neutralizing antibodies prior to challenge with virulent AHSV-4. No ELISA-reactive antibodies were present prior to challenge. A group of four seronegative control horses died after developing clinical signs and lesions typical of the pulmonary form of African horsesickness while the immunized horses were clinically normal. Increases in serum neutralizing and ELISA-reactive antibody ...
Green BE, Foil LD, Hagius SD, Issel CJ.Equine infectious anemia virus (EIAV) was injected intrathoracically into Aedes aegypti, Stomoxys calcitrans, and Tabanus fuscicostatus, and fed to Ae. aegypti in suspensions of either artificial blood of Eagle's Minimum Essential Medium. Insects were stored at -70 degrees C for up to 9 months before testing for the presence of EIAV. The viral tissue culture titers detected from stored insects were similar to those from insects tested at time 0.
Martínez-Torrecuadrada JL, Díaz-Laviada M, Roy P, Sánchez C, Vela C, Sánchez-Vizcaíno JM, Casal JI.African horsesickness virus serotype 4 (AHSV-4) outer capsid protein VP2, or VP2 and VP5 plus inner capsid protein VP7, derived from single or dual recombinant baculovirus expression vectors were used in different combinations to immunize horses. When the proteins were purified by affinity chromatography, the combination of all three proteins induced low levels of neutralizing antibodies and conferred protection against virulent virus challenge. However, purified VP2 or VP2 and VP5 in the absence of VP7 failed to induce neutralizing antibodies and protection. Immunization with non-purified pro...
Lichtenstein DL, Issel CJ, Montelaro RC.Equine infectious anemia virus (EIAV) provides a uniquely dynamic system in which to study the mechanism and role of genomic variation in lentiviral persistence and pathogenesis. We have used a Shetland pony model of infection to investigate the association of specific long terminal repeat (LTR) and env gene genomic sequences with the initiation of infection and the onset of disease. We analyzed viral RNA isolated from a pathogenic stock of virus (EIAV PV) and from plasma taken during the first disease episode from two ponies infected with EIAV PV. Overall sequence variation within gp90 was lo...
Timoney PJ.A highly contagious virus infection of horses, influenza is the single most important equine respiratory disease in many countries. Two subtypes of equine influenza virus have been identified, A/equine-1 and A/equine-2, neither of which immunologically cross-reacts. In the case of A/equine-2 virus, two lineages exist, American and European, which appear to have evolved independently of one another. The acute febrile respiratory disease characteristic of influenza is frequently complicated by secondary bacterial infection, especially in unvaccinated horses. Primarily a respiratory-borne infecti...
Langemeier JL, Cook SJ, Cook RF, Rushlow KE, Montelaro RC, Issel CJ.Control of equine infectious anemia (EIA) is currently based on detection of anti-EIA virus (EIAV) antibodies. However, serologic diagnostic methods may give false-negative results in infected horses that fail to respond adequately or are in the early stages of infection. We developed a reverse transcriptase nested PCR (RT-nPCR) assay for the detection of viral gag gene sequences in plasma from EIAV-infected horses. The ability of RT-nPCR to detect field strains of EIAV was investigated by assaying plasma samples from 71 horses stabled on EIA quarantine ranches. Positive PCR signals were detec...
Reisen WK, Hardy JL, Presser SB, Chiles RE.The vector competence of Culex tarsalis Coquillett from the Coachella Valley of California for western equine encephalomyelitis (WEE) and St. Louis encephalitis (SLE) viruses was monitored monthly from February to November 1993. The concentration of WEE virus required to infect 50% of the females increased during summer coincidentally with ambient temperature and was highest during July. Transmission rates of WEE virus were high during March, low during May-June, and high again during July-September. Females expressed both mesenteronal escape and salivary gland barriers limiting WEE virus diss...
Howard JJ, Grayson MA, White DJ, Oliver J.A regional surveillance system for eastern equine encephalitis (EEE) virus was established in central New York in 1984 after the 2nd human EEE fatality occurred in 1983. Extensive mosquito surveillance activities were coordinated with the rapid laboratory processing of mosquito specimens for EEE virus. Active surveillance for EEE infections in humans and equines also was initiated. Results of long-term surveillance detected the presence of multiple Culiseta breeding swamps. A 6-yr interepizootic period (1984-1989) was followed by 2 yr of equine EEE. In 1990, there were 7 equine cases and a rec...
Adeyefa CA, Tomori O, Akpavie SO, Awoseyi OA.Thirteen cases of a disease with a low morbidity and very high mortality in horses in Nigeria are described; the disease is characterised by fever (rectal temperature > or = 40 degrees C), generalised muscle spasms, ataxia, increased respiratory and heart rates and terminal lateral recumbency. The illness generally lasts three to five days but durations of 12 to 30 hours have been observed. Laboratory investigations, including histopathology and serology suggest a viral aetiology, possibly an alphavirus of the equine encephalitis group.
Smith KC, Mumford JA, Lakhani K.Four Welsh Mountain pony mares at 3 months of gestation and one mare at 5 months were inoculated intranasally with equid herpesvirus-1 (EHV-1: Ab4 isolate) at doses of 10(5) to 10(6.6) TCID50. All five mares became infected, but no cases of paresis or abortion occurred. On days 8, 9, 11, 12 (3-month-pregnant mares) and 13 (5-month-pregnant mare) after infection, a detailed examination of the pregnant uterus was made. Small numbers of vascular lesions with EHV-1 antigen expression in endothelial cells were present in the uteri of the early gestational mares; thrombi were rare and foci of thromb...
Taesuji M, Rattanamas K, Kulthonggate U, Mamom T, Ruenphet S.The immune responses of animals infected with African horse sickness (AHS) virus are determined by enzyme-linked immunosorbent assay (ELISA), complement fixation, and virus neutralization test. During the outbreaks of AHS in Thailand, the immune response after vaccination has been monitored using commercial test kits such as blocking ELISA, which are expensive imported products unavailable commercially in Thailand. This study aimed to assess the sensitivity and specificity of anti-AHS virus antibodies using dot blotting based on monovalent and polyvalent strains of live attenuated AHS vaccine....
Skowronek AJ, LaFranco L, Stone-Marschat MA, Burrage TG, Rebar AH, Laegreid WW.Infection of naive North American horses with 10(4) cell culture infectious doses (CCID50) of virulence variants of African horsesickness virus (AHSV), designated AHSV/4SP, AHSV/9PI, and AHSV/4PI, reproduced three classical forms of African horsesickness: acute (pulmonary), subacute (cardiac), and febrile, respectively. Distinct clinicopathologic and hemostatic abnormalities were associated with each form of disease. Hemostatic abnormalities included increased concentration of fibrin degradation products and prolongation of prothrombin, activated partial thromboplastin, and thrombin clotting t...
Gao X, Jiang CG, Wang XF, Lin YZ, Ma J, Han XE, Zhao LP, Shen RX, Xiang WH, Zhou JH.The contribution of S2 accessory gene of equine infectious anemia virus (EIAV) to the virulence of pathogenic strains was investigated in the present study by reverse mutation of all four consensus S2 mutation sites in an attenuated EIAV proviral strain, FDDV3-8, to the corresponding sequences of a highly pathogenic strain DV117. The S2 reverse-mutated recombinant strain FDDVS2r1-2-3-4 replicated with similar kinetics to FDDV3-8 in cultivated target cells. In contrast to the results of other studies of EIAV with dysfunctional S2, reverse mutation of S2 only transiently and moderately increased...
Galon EM, Macalanda AM, Garcia MM, Ibasco CJ, Garvida A, Ji S, Zafar I, Hasegawa Y, Liu M, Ybañez RH, Umemiya-Shirafuji R, Ybañez A, Claveria F....Tick-borne diseases (TBDs) considerably impair equine health and productivity. Moreover, TBDs, particularly equine piroplasmosis, impede international movement and trade of equids, which is a vital component of the global horse racing industry. In the Philippines, horse racing is a lucrative industry generating millions of USD annually. However, information on equine TBDs is scarce. This study intended to describe molecularly the equine tick-borne infections in a racehorse park in Cavite, Philippines and identify the risk factors associated with the infections. One hundred twenty-four (n = 124...
Newton JR, Wood JL, Castillo-Olivares FJ, Mumford JA.Serological analysis of blood samples submitted to the Animal Health Trust showed that during 1995, 185 of 9203 unvaccinated horses (2.0 per cent) tested positive for antibodies to equine arteritis virus (EAV), and that during 1996, 46 of 8851 unvaccinated horses (0.52 per cent) tested positive. During both years thoroughbreds were the predominant breed tested and only a small proportion of these (<0.3 per cent), consisting predominantly of imported mares, were seropositive. In contrast, among standardbred horses, from which samples were actively solicited in 1995, 84 of 454 (18.5 per cent) we...
Li J, Zhang X, Bai B, Zhang M, Ma W, Lin Y, Wang X, Wang XF.All lentiviruses encode a post-transcriptional transactivator, Rev, which mediates the export of viral mRNA from the nucleus to the cytoplasm and which is required for viral gene expression and viral replication. In the current study, we demonstrate that equine infectious anemia virus (EIAV), an equine lentivirus, encodes a second post-transcriptional transactivator that we designate Grev. Grev is encoded by a novel transcript with a single splicing event that was identified using reverse transcription-PCR (RT-PCR) and RNA-seq in EIAV-infected horse tissues and cells. Grev is about 18 kDa in...
Yıldırım Y, Yılmaz V, Yazıcı K, Öziç C, Ozkul A, Çağırgan AA.West Nile virus (WNV), a member of the Flaviviridae, is a major arbovirus that causes West Nile fever. Previous data showed the prevalence of the WNV serologically and molecular in Turkey, and the presence of lineage 1 in horses and humans has been reported. This is the first notification of partial phylogeny of WNV detected in donkeys in the northeast of Turkey (on the Iranian border). Blood serum samples collected from 25 donkeys without clinical symptoms were tested by RT-PCR. Sequence analysis of the sample detected as positive was performed. Multiple sequence alignments of reference seque...
Fong CK, Hsiung GD.Development of equine herpesvirus strain 82A was studied in cells from primary horse kidney (HOK) cultures and an equine dermis (ED) cell strain. HOK and ED cells are equally susceptible to the 82A virus infection and yield about the same amount of infectious virus. Intranuclear inclusions were present in both cell systems, but a ring-shaped syncytial formation was observed only in infected ED cells. Ultrastructural studies revealed the presence of dense granules 30 nm in diameter and characteristic star-like clusters of granules in the infected HOK cells, but these granules were rarely seen i...
Patel JR, Edington N.Eleven isolates of equine herpesvirus-1 (subtype 1) all infected the brain following intracerebral inoculation of 2 d.o. mice. Most isolates were from cases of paresis, abortion or respiratory disease in the U.K., but established strains were also included. They divided into two subgroups. The 5 less pathogenic isolates were characterized by being restricted predominantly to the olfactory lobes. The 6 pathogenic isolates included the three known to cause equine paresis and were detected in neurones throughout the brain as well as giving rise to viraemia and infecting bronchial and renal epithe...
Hamblin C, Mellor PS, Graham SD, Hooghuis H, Montejano RC, Cubillo MA, Boned J.A total of 256 sera collected from three species of domesticated equidae in four different Spanish provinces were examined 1-4 months after the administration of attenuated monovalent African horse sickness virus (AHSV) serotype 4 vaccine. Approximately 10% of the sera were negative by ELISA, virus neutralization, agar gel immuno-diffusion and complement fixation tests. Similar negative reactions were recorded with sera from two ponies after experimental primary vaccination. The rapid rise in antibodies in sera from these two ponies, after a second dose of vaccine, suggested they would probabl...
Mettler NE, Fernández AS, Di Santo MI, Pardo DA.Sera from 282 equines from Tandil country and surroundings were investigated searching for hemagglutination inhibition (HI), Complement fixation (CF), and Neutralizing (NT) antibodies against three flavivirus:Ilheus, St. Louis Encephalitis, and Yellow Fever from the Togaviridae family. Sera were collected between 3-20-79 and 11-25-80 from 10 different places in Tandil and Ayacucho countries. Animals ranged from 45 days to 27 years old. Forty nine of them reacted with one or more flavivirus by HI and/or CF tes representing a prevalence of 17.4% for this antigenic complex. Twenty four of them ne...
Quentin-Froignant C, Kappler-Gratias S, Top S, Bertagnoli S, Gallardo F.Equine herpesvirus 1 (EHV-1) is a causative agent of respiratory disorders, abortion and myeloencephalopathy in horses and has an important impact on equine health and economy. Several bacterial artificial chromosomes have already been developed and enabled identification and functional characterization of EHV-1 genes. Unfortunately, little is known about its replication. Here, the ANCHOR system was inserted by targeted homologous recombination into the equine herpesvirus genome. This insertion led to the conversion of EHV-1 DNA to auto-fluorescent spots easily detectable by fluorescence micro...
Fürstenau J, Richter MT, Erickson NA, Große R, Müller KE, Nobach D, Herden C, Rubbenstroth D, Mundhenk L.Borna disease is a progressive meningoencephalitis caused by spillover of the Borna disease virus 1 (BoDV-1) to horses and sheep and has gained attention due to its zoonotic potential. New World camelids are also highly susceptible to the disease; however, a comprehensive description of the pathological lesions and viral distribution is lacking for these hosts. Here, the authors describe the distribution and severity of inflammatory lesions in alpacas ( = 6) naturally affected by this disease in comparison to horses ( = 8) as known spillover hosts. In addition, the tissue and cellular distribu...
Bolfa P, Nolf M, Cadoré JL, Catoi C, Archer F, Dolmazon C, Mornex JF, Leroux C.EIA (Equine Infectious Anemia) is a blood-borne disease primarily transmitted by haematophagous insects or needle punctures. Other routes of transmission have been poorly explored. We evaluated the potential of EIAV (Equine Infectious Anemia Virus) to induce pulmonary lesions in naturally infected equids. Lungs from 77 EIAV seropositive horses have been collected in Romania and France. Three types of lesions have been scored on paraffin-embedded lungs: lymphocyte infiltration, bronchiolar inflammation, and thickness of the alveolar septa. Expression of the p26 EIAV capsid (CA) protein has been...
Turco S, Gabbianelli F, Mavian CN, Pietrucci D, De Paolis L, Gialletti R, Mechelli L, De Ciucis CG, Cappelli K, Dell'Anno F, Mecocci S, Donato GG....Papillomaviruses (PVs) are small, non-enveloped viruses, ubiquitous across the animal kingdom. PVs induce diverse forms of infection, such as cutaneous papillomas, genital papillomatosis, and carcinomas. During a survey on the fertility status of a mare, a novel PV (EcPV) has been identified using Next Generation Sequencing, and it was further confirmed with genome-walking PCR and Sanger sequencing. The complete circular genome 7607 bp long shares 67% average percentage of identity with EcPV9, EcPV2, EcPV1, and EcPV6, justifying a new classification as PV 10 (EcPV10). All EcPV genes are cons...
Gross DK, Hinchcliff KW, French PS, Goclan SA, Lahmers KK, Lauderdale M, Ellis JA, Haines DM, Slemons RD, Morley PS.The purpose of this experiment was to determine if exercising horses, infected with influenza virus, exacerbates the severity of clinical disease. Eight horses were trained on a treadmill for 42 days and then challenged with aerosolised influenza A/equine/Kentucky/91 (H3N8). Following challenge, 4 horses (exercise group) continued training for 28 days, while the other 4 horses (nonexercise group) were confined to their stalls. All horses developed clinical signs within 36 h of challenge (fever, coughing, and mucopurulent nasal discharge) and clinical scores were greater in the exercise group. ...
Singha H, Goyal SK, Malik P, Khurana SK, Singh RK.Equine infectious anemia (EIA)-a retroviral disease caused by equine infectious anemia virus (EIAV)-is a chronic, debilitating disease of horses, mules, and donkeys. EIAV infection has been reported worldwide and is recognized as pathogen of significant economic importance to the horse industry. This disease falls under regulatory control program in many countries including India. Control of EIA is based on identification of inapparent carriers by detection of antibodies to EIAV in serologic tests and "Stamping Out" policy. The current internationally accepted test for diagnosis of EIA is the ...
Andrews ES, Turell MJ.Emerging and re-emerging arboviruses continue to be a threat to global public health, and viral surveillance of mosquito populations is critical for mosquito control operations. Due to the tropical climate of many of the affected areas, it may be difficult to maintain a cold chain as the samples travel from collection sites to laboratories for testing. We determined how suboptimal holding temperatures affected the ability to detect viruses in pools of mosquitoes. Adult female Aedes albopictus and Ae. taeniorhynchus individuals were inoculated with chikungunya virus or Venezuelan equine encepha...
Field HJ, Awan AR, de la Fuente R.The compound (S)-9-(3-hydroxy-2-phosphonylmethoxypropyl)adenine (HPMPA) had been previously shown to be highly effective in treatment of EHV-1 in a murine model for the equine disease. This paper describes the isolation of a series of mutants resistant to the drug. Resistance was demonstrated in cell culture and one mutant was tested in a murine model. The resistant mutant was pathogenic for mice; infectious virus was recovered from respiratory tissues and blood at levels similar to the parental virus. However, the mutant showed a significant degree of resistance in vivo, thus proving the viru...
Dzieciatkowski T, Przybylski M, Cymerys J, Turowska A, Chmielewska A, Tucholska A, Banbura MW.Equine herpesvirus type 1 (EHV-1) is one of the major viral agents causing diseases in horses common worldwide. A variety of techniques, including PCR, have been used to diagnose EHV-1 infections. In this paper, an attempt of real-time PCR has been described, which uses specific fluorochrome-labeled TaqMan probes for detection of viral DNA. This method does not require post-amplification manipulations, thereby reducing the risk of cross-contamination. The assay was sensitive enough to detect EHV-1 sequences in different clinical samples, as well in mice neuronal cell cultures. The technique wa...
Patterson JS, Maes RK, Mullaney TP, Benson CL.An immunohistochemical (IHC) assay was developed for the detection of eastern equine encephalomyelitis (EEE) virus antigen in formalin-fixed, paraffin-embedded tissues. All cases of EEE diagnosed at the Michigan State University Animal Health Diagnostic Laboratory from 1991 through 1994 were evaluated. The diagnosis was based on histopathologic examination of the brain and confirmatory virus, isolation. Sections of cerebrum from 26 equids and 5 birds were assessed by IHC. Histologically normal brain tissues from 2 horses and 1 pheasant and brain tissues from 2 cases of equine neurologic diseas...
Gobeil PA, Yuan Z, Gault EA, Morgan IM, Campo MS, Nasir L.Equine sarcoids are skin tumours of horses caused by infection with BPV-1 or 2. Maintenance and replication of the viral genome depend upon the viral proteins E1 and E2. We examined the effects of an E2 specific siRNA on E2 and E1 viral gene expression, viral load and cell growth in BPV-1 transformed sarcoid-derived cells. Transfection with E2-siRNA caused a reduction in E2 and E1 mRNA expression as well as viral load, growth inhibition and decreased anchorage-independent growth. siRNA treated cells showed significantly higher apoptosis rates than control cells. Thus sequence specific targetin...
Koekemoer JJ, Dijk AA.Since protection against African horsesickness (AHS) is serotype-specific, rapid serotyping of AHSV is crucial to identify the correct vaccine serotype for efficient control of the spread of AHS outbreaks, especially when they occur in non-endemic regions. This paper describes the first one-day serotyping procedure that requires only a single RT-PCR and hybridization and which can identify multiple serotypes in mixed infections in one assay. The same region of genome segment 2 of all nine AHSV serotypes is amplified in a single RT-PCR. A universal primer set, designed to amplify the 5'-termina...
Nishimura M, Nakajima H.Using purified equine infectious anemia (EIA) virus labeled with 3H-glucosamine or 14C-protein hydrolysate, structural proteins were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. As a result, 2 glycoproteins and 10 proteins with molecular weights (mol wt) ranging from 12,000 to 115,000 daltons were demonstrated. Of 12 structural proteins, 3 proteins, namely a glycoprotein with mol wt of 76,000 (gp76) and 2 proteins with mol wt of 25,000 (p25) and 12,000 (p12), respectively, had distinct antigenic activity from one another in immunodiffusion. Development of antibodies a...
Perryman LE, O'Rourke KI, Mason PH, McGuire TC.Equine-murine xenohybridoma cells were produced using SP2/0 murine myeloma cells and splenic lymph node cells obtained from horses infected with 10(6) TCID50 of single cloned variants of equine infectious anaemia virus (EIAV). The xenohybridomas secreted equine IgG monoclonal antibodies reactive with EIAV in enzyme immunoassays employing purified virus. Seven antibodies were studied in detail. They bound to viral glycoproteins (gp90 or gp45) in radioimmunoprecipitation assays, and reacted with homologous EIAV as well as five other cloned variants of EIAV. When evaluated against a single cloned...
Laviada MD, Roy P, Sánchez-Vizcaíno JM, Casal JI.Segment 10 of the double-stranded RNA (dsRNA) genome from African horse sickness virus serotype 4 (AHSV-4) was cloned and sequenced. The sequence of the coding region showed a total length of 667 bp. Nucleotide comparisons showed a 95% sequence similarity between serotypes 4 and 9, and 76% between serotypes 4 and 3. cDNA clones containing the coding region were cloned in the vector pET3xb and expressed in Escherichia coli. The NS3 gene product was synthesised at very high level as an insoluble fusion protein. The recombinant protein was used in a differential ELISA to distinguish horses that w...
Turowska A, Pajak B, Godlewski MM, Dzieciatkowski T, Chmielewska A, Tucholska A, Banbura M.Viruses can reorganize the cytoskeleton and restructure the host cell transport machinery. During infection viruses use different cellular cues and signals to enlist the cytoskeleton for their mission. However, each virus specifically affects the cytoskeleton structure. Thus, the aim of our study was to investigate the cytoskeletal changes in homologous equine dermal (ED) and heterologous Vero cell lines infected with either equine herpesvirus 1 (EHV-1) strain Rac-H or Jan-E. We found that Rac-H strain disrupted actin fibers and reduced F-actin level in ED cells, whereas the virus did not infl...
Balena V, Pradhan SS, Bera BC, Anand T, Sansanwal R, Khetmalis R, Madhwal A, Bernela M, Supriya K, Pavulraj S, Tripathi BN, Virmani N.Equid alphaherpesvirus 1 (EHV-1) infection causes significant health problems in equines. The EHV-1 infection leads to abortion storm in mares, respiratory disease and myeloencephalopathy. Despite the wide use of vaccines, the outbreaks of EHV-1 infections keep occurring globally, suggesting the need for the development of improved vaccines. Gene deletion attenuated mutant viruses could be a good candidate for the development of modified live vaccines. Here, we report the generation of mutant EHV-1 by deleting virulence (glycoprotein E & internal repeat 6; IR6) and immune evasive (pUL43 &a...
Meng Q, Li S, Liu L, Xu J, Liu Y, Zhang Y, Zhang X, Shao Y.Equine Infectious Anemia Virus (EIAV), like other lentiviruses, has a transmembrane glycoprotein with an unusually long cytoplasmic tail (CT). Viral envelope (Env) proteins having CT truncations just downstream the putative membrane-spanning domain (PMSD) are assumed to exist among all wild-type budded virions, and also in some cell-adapted strains. To determine whether CT-truncated Env proteins can cause particularly deleterious effects on the Env expressing cells and/or their neighboring cells, plasmids encoding codon-optimized env gene including full-length (pE863) or CT-truncated (pE686* a...
Savini F, Gallina L, Prosperi A, Battilani M, Bettini G, Scagliarini A.BPV-1 is known as the main causative agent of equine sarcoid, but the virus has also been detected in skin and blood of healthy horses. Previous reports demonstrated the presence of E5 variants in sarcoids of donkeys and horses; we investigated whether this genetic variability might be also found in BPV-1, PBMC associated, of sub-clinically infected horses. With this aim, we analyzed the E5 gene of 21 BPV-1 strains from diseased and sub-clinically infected horses. Our analyses lead us to demonstrate that multiple sequence variants can be present in the blood of sub-clinically infected horses, ...
