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.
Alonso JM, Filho PTH, Ávila AR, Machado VMV, Hataka A, Bueno LMC, Alves ALG, Hussni CA, Rodrigues CA, Watanabe MJ.There are no previous reports of cranial meningocele in horses. In this report, we present the case of a 1-day-old male Quarter Horse that was born with a mass in the occipital region. The newborn was brought to the veterinary hospital, and a meningocele was diagnosed. The patient then underwent surgical closure of the defect. After an initial favorable response, the patient displayed signs of infection. The antibiotic therapy was changed, and the patient's condition improved. On the 13th postoperative day, the patient exhibited ataxia, difficulty standing, and limb hypertonia. Hydrocephalus w...
Following the recent confirmation of cases of equine viral arteritis in stallions in south-west England, James Crabtree of Equine Reproductive Services (UK) discusses the disease and its potential routes of spread into and around the UK.
Tsachev I, Baymakova M, Pantchev N.Lyme borreliosis, granulocytic anaplasmosis and monocytic ehrlichiosis are well studied in humans and dogs. In horses, these diseases are not widely investigated and limited information is available about their occurrence. The purpose of this study was to present the first ELISA-based report on the seroprevalence of Anaplasma phagocytophilum, Ehrlichia spp. and Borrelia burgdorferi in horses from Northern Bulgaria. A total of 192 horses were investigated from three regions in Northern Bulgaria (Northwestern, North-Central and Northeastern Bulgaria). All equine sera were tested for A. phagocyto...
El-Hage CM, Bannai H, Wiethoelter AK, Firestone SM, Heislers CM, Allen JL, Waller AS, Gilkerson JR.To determine the nature of serological responses in Australian horses using a commercial duplex indirect ELISA (iELISA) following vaccination against strangles. Methods: A group (n = 19) of client-owned horses from five properties were recruited to receive a primary course of a Streptococcus equi subsp. equi (S. equi) extract vaccine. Serological responses were determined by duplex iELISA incorporating S. equi-specific fragments of two cell wall proteins, SEQ2190 and SeM (antigens (Ag) A and C, respectively). Methods: The horses were administered a primary strangles vaccination course. Blood w...
Ebani VV.Anaplasma phagocytophilum and Rickettsia spp. are tick-borne bacteria of veterinary and human concern. In view of the One-Health concept, the present study wanted to evaluate the spreading of these pathogens in horses living in central Italy. In particular, the aim of the investigation was to verify the exposure to A. phagocytophilum in order to update the prevalence of this pathogen in the equine population from this area, and to spotted fever group (SFG) Rickettsia spp. to evaluate a possible role of horses in the epidemiology of rickettsiosis. Indirect immunofluorescent assay was carried ou...
Gieling F, Peters S, Erichsen C, Richards RG, Zeiter S, Moriarty TF.Bacterial osteomyelitis in veterinary patients can be challenging to diagnose and treat, given limited therapeutic options and reported success rates. Osteomyelitis is frequently associated with surgical implant devices, including those required to optimise stability and healing of fractures. However, management of osteomyelitis sometimes necessitates the removal of these surgical implant devices in order to eradicate infection or limit implant-related osteolysis. The goal of this article is to provide a general and species-specific review of bacterial osteomyelitis in a selection of domestic ...
Nemoto M, Yamayoshi S, Bannai H, Tsujimura K, Kokado H, Kawaoka Y, Yamanaka T.Equine influenza virus is an important pathogen for the horse industry because of its economic impact, and vaccination is a key control measure. Our previous work suggested that a mutation at position 144 in the hemagglutinin of Florida sublineage clade 2 viruses reduces the cross-neutralizing activity of antiserum against a former vaccine strain. To confirm this suggestion, here, we generated viruses by reverse genetics. Antibody titers against the mutated viruses were one-tenth to one-sixteenth of those against the former vaccine strain. Our findings confirm that this single amino acid subst...
Lu G, Ou J, Ji J, Ren Z, Hu X, Wang C, Li S.Getah virus (GETV) is a mosquito-borne virus that was first determined in Malaysia in 1955, and can infect humans and multiple other mammals. GETV infection in horses has been reported in Japan and India, and causes great economic losses. In China, GETV has been identified in mosquitoes, pigs, foxes, and cattle with a wide geographical distribution, but has not been detected in horses. In August 2018, a sudden onset of fever was observed in racehorse in an equestrian training center in Guangdong Province in southern China. Blood samples were collected from the sick horse, and PCR/RT-PCR analys...
Peng Z, Shen D, Zhang D, Li X, Wang L, Zhai Q, Hou Z, Li H.The equine Parascaris spp. is large, parasitic nematodes, and predominantly focuses on the intestine of foals and young weanlings. There are two roundworms, Parascaris equorum and Parascaris univalens, recognized among equine hosts. In this study, all fifty-nine Parascaris worms were harvested from three different equine hosts (twenty specimens from Equus zebra, twenty specimens from E. caballus, and nineteen specimens from E. asinus). The ribosomal gene (ITS) and mitochondrial genes (cox1 and nadh1) were amplified to identify and genetically characterize these worms. Analysis of ITS sequences...
Richardson JS, Parrera GS, Astacio H, Sahota H, Anderson DM, Hall C, Babinchak T.Botulism is a rare, life-threatening paralytic illness. Botulism Antitoxin Heptavalent (A,B,C,D,E,F,G)-(Equine) (BAT) manufactured by Emergent BioSolutions Canada Inc is an equine-derived heptavalent botulinum antitoxin product indicated for the treatment of symptomatic botulism following documented or suspected exposure to botulinum neurotoxin serotypes A-G in adults and pediatric patients. BAT product was US-licensed in 2013. In the United States, from October 2014 through July 2017, safety and clinical outcomes data were collected under a registry for patients treated with BAT product. Regi...
Vázquez-Boland JA, Meijer WG.Rhodococcus equi is the only recognized animal pathogenic species within an extended genus of metabolically versatile Actinobacteria of considerable biotechnological interest. Best known as a horse pathogen, R. equi is commonly isolated from other animal species, particularly pigs and ruminants, and causes severe opportunistic infections in people. As typical in the rhodococci, R. equi niche specialization is extrachromosomally determined, via a conjugative virulence plasmid that promotes intramacrophage survival. Progress in the molecular understanding of R. equi and its recent rise as a nove...
Munhoz AD, Souza MA, Costa SCL, Freitas JS, Silva AND, Lacerda LC, Cruz RDS, Albuquerque GR, Pereira MJS.The aim of this study was to determine the frequency and factors associated with Toxoplasma gondii in naturally infected equids in northeastern Brazil. Serum samples from 569 equids (528 horses, 8 mules and 33 donkeys) were subjected to the indirect fluorescent antibody test. Generalized linear models were used to evaluate associated factors. Among the 569 animals sampled, 118 (30.6%) living in rural areas and 14 (26.42%) in urban areas were seropositive (p>0.05). Seropositive animals were observed on 95% of the farms and in all the municipalities. Donkeys/mules as the host, presence of dom...
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...
Sears KP, Kappmeyer LS, Wise LN, Silva M, Ueti MW, White S, Reif KE, Knowles DP.Theileria equi infection, exotic to the United States has reemerged through intravenous (iatrogenic) and tick-borne transmission. Surveillance at the US-Mexico border identified a new species, Theileria haneyi, (T. haneyi) (EP = Eagle Pass, Texas) which warranted additional investigation due to inability to detect by PCR targeting of T. equi ema-1 and EMA-1-cELISA validated for T. equi. Infection dynamics of T. haneyi were evaluated, including ability to superinfect in the presence of T. equi-Texas (T. equi), the isolate responsible for the reemergence of T. equi in the U S. Experimental i...
Dall Agnol AM, Beuttemmuller EA, Pilz D, Leme RA, Saporiti V, Headley SA, Alfieri AF, Alfieri AA.Equid gammaherpesvirus 2 (EHV-2) and 5 (EHV-5) are members of the Herpesviridae family and have been reported in horse populations worldwide. This study aimed to evaluate the presence of herpesvirus DNA in the upper respiratory tract of horses. Twenty-six nasal swabs were collected from asymptomatic adult horses of two different horse farms (A, n = 18; B, n = 8), both located in Southern Brazil. The EHV-1, EHV-2, EHV-4, and EHV-5 DNA analyses were performed using nested PCR assays targeting the glycoprotein B gene. Four (15.3%) and 12 (46.1%) of the 26 nasal swab samples were positive ...
Riddin MA, Venter GJ, Labuschagne K, Villet MH.African horse sickness (AHS), a disease of equids caused by the AHS virus, is of major concern in South Africa. With mortality reaching up to 95% in susceptible horses and the apparent reoccurrence of cases in regions deemed non-endemic, most particularly the Eastern Cape, epidemiological research into factors contributing to the increase in the range of this economically important virus became imperative. The vectors, Culicoides (Diptera: Ceratopogonidae), are considered unable to proliferate during the unfavourable climatic conditions experienced in winter in the province, although the annua...
Stejskalova K, Janova E, Horecky C, Horecka E, Vaclavek P, Hubalek Z, Relling K, Cvanova M, D'Amico G, Mihalca AD, Modry D, Knoll A, Horin P.The West Nile virus (WNV) is a mosquito-borne flavivirus causing meningoencephalitis in humans and animals. Due to their particular susceptibility to WNV infection, horses serve as a sentinel species. In a population of Romanian semi-feral horses living in the Danube delta region, we have analyzed the distribution of candidate polymorphic genetic markers between anti WNV-IgG seropositive and seronegative horses. Thirty-six SNPs located in 28 immunity-related genes and 26 microsatellites located in the MHC and LY49 complex genomic regions were genotyped in 57 seropositive and 32 seronegative ho...
Valença SRFA, Ribeiro-Andrade M, Moré G, Albuquerque PPF, Pinheiro Júnior JW, Mota RA.The aim of this study was to determine the prevalence of infection by Sarcocystis neurona in horses and identify potential risk factors. Were analyzed 427 samples from 36 farms in 21 municipalities in the Alagoas State, Brazil. Presence of anti-S. neurona antibodies was diagnosed by indirect immunofluorescence antibody test (IFAT) and was confirmed using the immunoblot test. Risk factors were assessed through investigative questionnaires on animal management on the farms. The prevalence of anti-S.neurona antibodies was 2.8% (confidence interval, CI: 1.5-4.9%) from IFAT and 1.6% (CI:0.8-3.34%) ...
Trumpp KM, Parsley AL, Lewis MJ, Camp JW, Taylor SD.Tick paralysis has not been reported in horses in North America. Results: Two American Miniature horses were examined for progressive weakness and recumbency. Numerous ticks (Dermacentor variabilis) were found on both horses. Horse 1 was recumbent (grade 5/5 gait deficit) on presentation, whereas Horse 2 was standing but ataxic (grade 4/5 gait deficit) and tetraparetic. Both horses had decreased tongue and tail muscle tone, and had normal spinal reflexes. Cerebrospinal fluid cytology was normal. Equine herpesvirus-1 testing was negative. Unassigned: Ticks were removed within 24 hours of pres...
Peng TL, Armiladiana MM, Ruhil HH, Maizan M, Choong SS.The occurrence of Setaria digitata in a horse is reported for the first time in Malaysia. An 8-year-old Thoroughbred cross mare was referred to the University Veterinary Clinic with the primary complaint of corneal opacity and excessive eye discharge. After initial treatment with Terramycin eye ointment, corneal opacity cleared partially to reveal a moving thread-like cylindrical worm in the anterior chamber of the eye. The parasite was successfully removed surgically, and examination under the light microscope revealed that the isolated worm (length = 45 mm) was a 5th stage larva of S. ...
Azab W, Bedair S, Abdelgawad A, Eschke K, Farag GK, Abdel-Raheim A, Greenwood AD, Osterrieder N, Ali AAH.Equid herpesviruses (EHVs) threaten equine health and can cause significant economic losses to the equine industry worldwide. Different equid herpesviruses, EHV-1, EHV-2, EHV-4 and EHV5 are regularly detected among horse populations. In Egypt, monitoring is sporadic but EHV-1 or EHV-4 have been reported to circulate in the horse population. However, there is a lack of reports related to infection and health status of horses, likely due to the absence of regular diagnostic procedures. In the current study, the circulation of four infectious equid herpesviruses (EHV-1, EHV-2, EHV-4 and EHV-5) am...
Spence KL, Slater J, Rosanowski SM, Cardwell JM.The international nature of the equine industry provides opportunities for the spread of infectious diseases between countries. While incursions of exotic diseases into the United Kingdom (UK) equine population have been rare, the potential socioeconomic and welfare impacts are a significant concern. However, little is known about leisure horse owners' ability or willingness to prepare for an exotic disease incursion. The objectives of this study were to describe UK leisure horse owners' awareness and perceptions of exotic diseases, and to identify clusters of horse owners characterised by the...
Al-Kass Z, Eriksson E, Bagge E, Wallgren M, Morrell JM.Although artificial insemination (AI) was developed as a means of controlling disease transmission, pathogens can still be transmitted to females in semen used for AI. In addition, bacteria can cause deterioration in sperm quality during storage. Semen becomes contaminated by the male's normal bacterial flora as it passes out of the reproductive tract but potential pathogens may also contaminate the semen. Therefore, semen samples from stallions to be used for AI are tested before the breeding season to minimize transmission of pathogens to inseminated mares. In Sweden, semen samples are teste...
Nam B, Mekuria Z, Carossino M, Li G, Zheng Y, Zhang J, Cook RF, Shuck KM, Campos JR, Squires EL, Troedsson MHT, Timoney PJ, Balasuriya UBR.Equine arteritis virus (EAV) is the causative agent of equine viral arteritis (EVA), a reproductive and respiratory disease of horses. Following natural infection, 10 to 70% of infected stallions can become carriers of EAV and continue to shed virus in the semen. In this study, sequential viruses isolated from nasal secretions, buffy coat cells, and semen of seven experimentally infected and two naturally infected EAV carrier stallions were deep sequenced to elucidate the intrahost microevolutionary process after a single transmission event. Analysis of variants from nasal secretions and buffy...
Jansen S, Heitmann A, Lühken R, Leggewie M, Helms M, Badusche M, Rossini G, Schmidt-Chanasit J, Tannich E.The continuous circulation of West Nile virus (WNV) in Central, South and East Europe and its recent detection in several dead birds and two horses in Germany highlights the need for information on WNV vector competence of mosquitoes from Central Europe. Therefore, three common Culex species (Culex pipiens biotype pipiens, Culex pipiens biotype molestus and Culex torrentium) from Germany were orally infected with WNV and kept at 18 °C, 21 °C, 24 °C or 27 °C for 14 or 21 days post infection (dpi). Thereafter viable WNV was present in the saliva in all tested taxa, but only at incubation tem...
Kuroda T, Kinoshita Y, Niwa H, Shinzaki Y, Tamura N, Hobo S, Kuwano A.Meticillin-resistant Staphylococcus aureus (MRSA) infections have been confirmed in hospitalised Thoroughbred racehorses at the hospitals of two training centres in Japan since 2009. To investigate the source of infection, the authors examined the rate of nasal MRSA colonisation in 600 healthy Thoroughbred racehorses, 53 veterinarians and 16 office staff at the racehorse hospitals of the two training centres. MRSA was not isolated from healthy Thoroughbred racehorses or hospital office staff. However, MRSA was isolated from 16 veterinarians (30.1 per cent), and the colonisation rate was signif...
Del Piero F, Wilkins PA, Dubovi EJ, Biolatti B, Cantile C.Natural eastern equine encephalitis alphavirus (EEEV) infection was diagnosed in two adult horses with anorexia and colic, changes in sensorium, hyperexcitability, and terminal severe depression. Myocardium, tunica muscularis of stomach, intestine, urinary bladder, and spleen capsule had coagulative necrosis and perivascular lymphocytic infiltrate. Central nervous system (CNS) lesions were diffuse polioencephalomyelitis with leptomeningitis characterized by perivascular T lymphocyte cuffing, marked gliosis, neuronophagia, and multifocal microabscesses. Lesions were more prominent within cerebr...
Wagner B, Glaser A, Hillegas JM, Erb H, Gold C, Freer H.West Nile virus (WNV) is a zoonotic pathogen of global importance. In horses with neurological signs, detection of WNV-specific immunoglobulin M (IgM) in serum is widely used to identify clinical cases of WNV encephalitis. Here, we describe the development of two monoclonal antibodies (mAbs) to equine IgM which were used in a WNV IgM-specific enzyme-linked immunosorbent assay (ELISA). Their performance was compared to an established assay based on polyclonal anti-IgM. Check test serum samples from the National Veterinary Service Laboratory (NVSL) were used to evaluate the performance of the th...
Netolitzky DJ, Schmaltz FL, Parker MD, Rayner GA, Fisher GR, Trent DW, Bader DE, Nagata LP.The complete nucleotide sequence of the 71V-1658 strain of western equine encephalitis virus (WEE) was determined (minus 25 nucleotides from the 5' end). A 5' RACE reaction was used to sequence the 5' terminus from WEE strain CBA87. The deduced WEE genome was 11508 nucleotides in length, excluding the 5' cap nucleotide and 3' poly(A) tail. The nucleotide composition was 28% A, 25% C, 25% G and 22% U. Comparison with partial WEE sequences of strain 5614 (nsP2-nsP3 of the nonstructural region) and strain BFS1703 (26S structural region) revealed comparatively little variation; a total of 149 nucl...
Kinde H, Mathews M, Ash L, St Leger J.Two horses, a 16-year-old male Holsteiner and a 5-year-old male miniature horse, were diagnosed with halicephalobiasis at the California Veterinary Diagnostic Laboratory System, San Bernardino Branch, in April and June of 1998. Over a period of 4 weeks, the Holsteiner horse developed renal dysfunction, blepharospasm, and blindness in the right eye. A 15-cm-diameter mass was detected on ultrasound examination in the right kidney. Terminally, the animal developed seizures and was euthanized. The miniature horse had a 6-week-long illness characterized by testicular enlargement and uveitis. This a...
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 ...
Den Boon JA, Spaan WJ, Snijder EJ.The expression of the genetic information of equine arteritis virus (EAV), an arterivirus, involves the synthesis of six subgenomic (sg) mRNAs. These are 5' and 3' coterminal since they are composed of a leader and a body sequence, which are identical to the 5' and 3' ends of the genome, respectively. Previously, it has been suggested that cis-splicing of a genome-length precursor RNA is involved in their synthesis. This was reevaluated in a comparative analysis of the sg RNA synthesis of EAV, the coronavirus mouse hepatitis virus (MHV), and the alphavirus Sindbis virus. UV transcription mappi...
Nygaard TK, Liu M, McClure MJ, Lei B.Heme is a preferred iron source of bacterial pathogens. Streptococcus equi subspecies equi is a bacterial pathogen that causes strangles in horses. Whether S. equi has a heme acquisition transporter is unknown. Results: An S. equi genome database was blasted with the heme binding proteins Shp and HtsA of Streptococcus pyogenes, and found that S. equi has the homologue of Shp (designated SeShp) and HtsA (designated SeHtsA). Tag-free recombinant SeShp and SeHtsA and 6xHis-tagged SeHtsA (SeHtsAHis) were prepared and characterized. Purified holoSeShp and holoSeHtsA bind Fe(II)-protoporphyrin IX (h...
Wang X, Wang S, Lin Y, Jiang C, Ma J, Zhao L, Lv X, Wang F, Shen R, Kong X, Zhou J.A lentiviral vaccine, live attenuated equine infectious anemia virus (EIAV) vaccine, was developed in the 1970s, and this has made tremendous contributions to the control of equine infectious anemia (EIA) in China. Four key virus strains were generated during the attenuation of the EIAV vaccine: the original Liao-Ning strain (EIAV(LN40)), a donkey-adapted virulent strain (EIAV(DV117)), a donkey-leukocyte-attenuated vaccine strain (EIAV(DLV121)), and a fetal donkey dermal cell (FDD)-adapted vaccine strain (EIAV(FDDV13)). In this study, we analyzed the proviral genomes of these four EIAV strains...
Mancianti F.Feline leishmaniasis (FL) is a quite uncommon feature. Clinical disease has been described in cats since nineties begin. More than 40 reports in world literature have been referred, but the clinical cases have been only recently well defined. Most of the reports focus on infected cats living in endemic areas, even if, more recently FL due to Leishmania infantum was found in Sao Paulo State, in Brazil where autochthonous human or canine leishmaniasis cases have never reported. In Europe clinical cases of FL have been described from Portugal, France, Spain and Italy from 1996 to 2002. When a typ...
Alam ME, Kamal MM, Rahman M, Kabir A, Islam MS, Hassan J.Anthrax is a rapidly fatal infectious disease affecting herbivores and people. In the farm animals, cattle and sheep are more susceptible, followed by goats and horses, while dwarf pigs and Algerian sheep are relatively resistant. Bacillus anthracis, the causative agent of anthrax, produces spores and persists for decades in the soil, initiating an outbreak through a favorable climate shift. Anthrax is enzootic in many Asian and African countries, and is reported in Australia, some parts of Europe, and America. The clinical courses of this disease in animals are peracute, acute, subacute, and ...
Sangal V, Goodfellow M, Jones AL, Sutcliffe IC.Opinion 106 of the Judicial Commission has clarified the nomenclature of the taxon variously named , ' and . As a consequence, we present here the genus name and that of its nomenclatural type species, comb. nov., for valid publication and propose the reclassification of four rhodococcal species as novel combinations in the genus, namely Guo et al. 2015 comb. nov., Kämpfer . 2014 comb. nov., Li . 2015 comb. nov. and Lee . 2019 comb. nov. In addition, we note that a clinical isolate, strain 86-07 (=W8901), likely represents an additional species within the genus . Nearly a century after ...
Kim HJ, Yong TS, Shin MH, Lee KJ, Park GM, Suvonkulov U, Kovalenko D, Yu HS.Echinococcosis occurs mainly in areas with heavy livestock farming, such as Central Asia, America, and Australia. Echinococcus granulosus sensu lato (s.l.) infection causes echinococcosis in intermediate hosts, such as sheep, cattle, goats, camels, and horses. Numerous cases of echinococcosis occur in Uzbekistan as stock farming is a primary industry. Epidemiological and genetic studies of E. granulosus s.l. are very important for mitigating its impact on public health and the economy; however, there are no such studies on E. granulosus s.l. in Uzbekistan. In the present study, to determine wh...
Del Piero F.Equine viral arteritis (EVA) can cause prominent economic losses for the equine industry. The purpose of this review is to provide the pathologist some familiarity with the clinical history, lesions, pathogenesis, and diagnosis of EVA. EVA is caused by an arterivirus (equine arteritis virus, EAV), and the vascular system is the principal but not unique viral target. EVA has variable presentations, including interstitial pneumonia, panvasculitis with edema, thrombosis and hemorrhage, lymphoid necrosis, renal tubular necrosis, abortion, and inflammation of male accessory genital glands. EAV anti...
Diaz-San Segundo F, Dias CC, Moraes MP, Weiss M, Perez-Martin E, Owens G, Custer M, Kamrud K, de los Santos T, Grubman MJ.We have previously shown that delivery of the porcine type I interferon gene (poIFN-α/β) with a replication-defective human adenovirus vector (adenovirus 5 [Ad5]) can sterilely protect swine challenged with foot-and-mouth disease virus (FMDV) 1 day later. However, the need of relatively high doses of Ad5 limits the applicability of such a control strategy in the livestock industry. Venezuelan equine encephalitis virus (VEE) empty replicon particles (VRPs) can induce rapid protection of mice against either homologous or, in some cases, heterologous virus challenge. As an alternative approach ...
Robertson AT, Caughman GB, Gray WL, Baumann RP, Staczek J, O'Callaghan DJ.Equine herpesvirus type 1 (EHV-1) gene expression is coordinately regulated in an alpha, beta, gamma fashion. Viral alpha gene products include a 6.0-kb immediate early (IE) mRNA species (W. L. Gray et al., 1987, Virology 158, 79-87) and at least four closely related IE polypeptides (IEPs) (G.B. Caughman et al., 1985, Virology 145, 49-61). In this report, we describe results obtained from a series of in vitro translation experiments which were performed in an effort to characterize the IEPs and identify the mechanism by which individual IE protein species are generated. Our data indicate that ...
Munday JS, Knight CG, Luff JA.Papillomaviruses (PVs) are well recognized to cause pre-neoplastic and neoplastic diseases in humans. Similarly, there is increasing evidence that PVs play a significant role in the development of pre-neoplastic and neoplastic diseases of the haired skin of dogs and cats, and the mucosa of horses. As the mechanisms by which PVs cause neoplasia are well studied in humans, it is valuable to compare the PV-induced neoplasms of humans with similar PV-associated neoplasms in the companion animal species. In the second part of this comparative review, the pre-neoplastic and neoplastic diseases thoug...
McFrederick QS, Haselkorn TS, Verocai GG, Jaenike J.Parasites in the genus Onchocerca infect humans, ruminants, camels, horses, suids, and canids, with effects ranging from relatively benign to debilitating. In North America, Onchocerca cervipedis is the sole species known to infect cervids, while at least 5 Onchocerca species infect Eurasian cervids. In this study, we report the discovery of a cervid-parasitizing Onchocerca only distantly related to O. cervipedis. To reconstruct the phylogenetic history of the genus Onchocerca, we used newly acquired DNA sequence from O. cervipedis (from moose in Northwest Territories, Canada) and from the new...
Gibson CA, Daniels RS, Oxford JS, McCauley JW.The nucleotide sequences of ten haemagglutinin genes of representative H7N7 equine influenza viruses isolated between 1956 and 1977 have been determined by primer extension sequencing. Their nucleotide and deduced amino acid sequences demonstrate a high degree of homology. These equine viruses can be divided into two distinct subgroups, the prototype-like, and a group comprising the early American isolates and the remaining equine viruses. The equine H7 haemagglutinins form a quite distinct group compared to H7 haemagglutinins isolated from other species. Each of these equine H7 haemagglutinin...
Chang YF, Novosel V, Dubovi E, Wong SJ, Chu FK, Chang CF, Del Piero F, Shin S, Lein DH.Human blood collected from two patients from Westchester County, New York with human granulocytic ehrlichia (HGE) infection was inoculated into two ponies. Inoculated ponies developed clinical signs similar to a previous report (Madigan et al., 1995). Histopathological changes involved follicular hyperplasia of lymphoid tissues. HGE DNA was detected by PCR in muscle, fascia, peritoneum, and adrenal gland after the ponies produced a high level of antibodies to HGE. We suggest that HGE may reside in poorly vascularized connective tissues, where the antibodies may have some difficulties to penetr...
Montagnier L.Recent data indicate that the lymphadenopathy-associated virus (LAV) is morphologically similar to animal lentiviruses, such as equine infectious anemia and visna viruses. This finding, together with the cross-reactivity of the core proteins of LAV with those of the equine infectious anemia virus and a similarity in genome structure and biological properties, allows LAV to be placed in the retroviral subfamily of Lentivirinae. Molecular data indicate a high degree of genetic variation of the virus, especially in the envelope gene, which have important implications for the origin of the virus (...
Morley PS, Hanson LK, Bogdan JR, Townsend HG, Appleton JA, Haines DM.Antibodies specific for equine influenza viruses are usually quantified using single radial hemolysis (SRH), hemagglutination inhibition (HI) or virus neutralization (VN). Neutralizing antibodies are thought to provide optimum protection to challenged animals. The purpose of this study was to determine the extent to which SRH and HI assays detect antibodies which neutralize equine influenza viruses. Acute and convalescent sera from 41 horses were analyzed using VN, SRH, and HI assays. These horses were present in a population of Thoroughbred racehorses during an epidemic of upper respiratory t...
Rosati S, Profiti M, Lorenzetti R, Bandecchi P, Mannelli A, Ortoffi M, Tolari F, Ciabatti IM.Among animal lentiviruses, Feline immunodeficiency virus (FIV), Equine infectious anaemia virus (EIAV) and Small ruminant lentiviruses (SRLV) are important pathogens associated with a variety of clinical pictures including immunodeficiency, anaemia, arthritis, pneumonia. The detection of viral antibody response represents a practical diagnostic approach in all lentivirus infections since they remain detectable long life. Capsid antigen (CA) is the major viral core protein and specific antibodies against this antigen are usually first recognised in infected sheep, goat and horse, remaining dete...
Okoko T, Blagova EV, Whittingham JL, Dover LG, Wilkinson AJ.Virulence and host range in Rhodococcus equi depends on the variable pathogenicity island of their virulence plasmids. Notable gene products are a family of small secreted virulence-associated proteins (Vaps) that are critical to intramacrophagic proliferation. Equine-adapted strains, which cause severe pyogranulomatous pneumonia in foals, produce a cell-associated VapA that is necessary for virulence, alongside five other secreted homologues. In the absence of biochemical insight, attention has turned to the structures of these proteins to develop a functional hypothesis. Recent studies have ...
Nagata LP, Hu WG, Masri SA, Rayner GA, Schmaltz FL, Das D, Wu J, Long MC, Chan C, Proll D, Jager S, Jebailey L, Suresh MR, Wong JP.The efficacy of a DNA vaccine against western equine encephalitis (WEE) infection in mice was evaluated. The 26S structural region was expressed, in vitro from an internal T7 promoter using a rabbit reticulysate transcription/translation system; and from a CMV promoter after transfection into Vero cell monolayers. The proteins synthesized were reactive with anti-WEE virus (WEEV) antibodies, both in western blot analysis and histochemical staining, respectively. When the DNA vaccine plasmid, pVHX-6, was administered intraepidermally to mice, followed by challenge in a lethal mouse model, the le...
Ramsauer AS, Badenhorst M, Cavalleri JV.Equine parvovirus hepatitis (EqPV-H) was first described in 2018 in a fatal case of Theiler's disease which followed the administration of an equine-origin biological product. The virus has since been frequently identified in serum and liver tissue of horses affected by Theiler's disease-an acute, severe hepatitis characterised by fulminant hepatic necrosis with a fatal outcome in most cases. EqPV-H is hepatotropic, appears to be associated with subclinical to severe hepatitis in horses, and is a likely cause of Theiler's disease. Although this disease is most frequently reported following the...
Grady GF, Maxfield HK, Hildreth SW, Timperi RJ, Gilfillan RF, Rosenau BJ, Francy DB, Calisher CH, Marcus LC, Madoff MA.Reappearance of eastern equine encephalitis (EEE) in Massachusetts residents in the 1970's provided an opportunity to assess the predictive value of data on rainfall, EEE in horses, and carriage of EEE virus (EEEV) by mosquitoes, factors which had been studied annually since the last EEE outbreak in 1955-1956. The cycle of multiple cases during 1973-1975 started in a second consecutive year of rainfall that exceeded the annual mean by more than 20 cm, conditions recapitulating the 1955-1956 experience. In 1973, widespread EEE fatalities in horses presaged human cases, another recapitulation of...
Middleton JR, Fales WH, Luby CD, Oaks JL, Sanchez S, Kinyon JM, Wu CC, Maddox CW, Welsh RD, Hartmann F.Staphylococcus aureus isolates (n = 70) from 65 patients (36 canine, 18 equine, 7 bovine, 2 avian, and 2 feline) at seven veterinary teaching hospitals in the United States were studied. The majority of patients (83%) with an S. aureus infection were canine and equine, but this may have reflected a sample bias based on clinic case loads and diagnostic lab submissions at the participating institutions. Fourteen percent of patients with an S. aureus infection were infected with a methicillin-resistant S. aureus (MRSA) isolate. Six of seven institutions had at least one MRSA infection during the ...
Everard CO, Fraser-Chanpong GM, James AC, Butcher LV.Sera from 1,206 livestock animals and chickens on Grenada and Trinidad were tested for leptospiral antibodies by the microscopic agglutination test. 376 of the sera were positive (25% of those tested on Grenada and 44% on Trinidad). The positive sera were obtained from 25% of 324 cattle, 35% of 130 pigs, 35% of 146 sheep, 25% of 44 goats and 11% of 175 chickens on Grenada; and 92% of 26 cattle, 53% of 122 pigs, 76% of 87 horses and donkeys and 11% of 144 chickens on Trinidad. Eight sera from ducks and geese on Trinidad were tested and found to be negative. The serogroups most commonly found to...
Cavalleri JV, Korbacska-Kutasi O, Leblond A, Paillot R, Pusterla N, Steinmann E, Tomlinson J.Horses and other equids can be infected with several viruses of the family Flaviviridae, belonging to the genus Flavivirus and Hepacivirus. This consensus statement focuses on viruses with known occurrence in Europe, with the objective to summarize the current literature and formulate clinically relevant evidence-based recommendations regarding clinical disease, diagnosis, treatment, and prevention. The viruses circulating in Europe include West Nile virus, tick-borne encephalitis virus, Usutu virus, Louping ill virus and the equine hepacivirus. West Nile virus and Usutu virus are mosquito-bor...
