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.
Kim DY, Johnson PJ, Senter D.A 9-year-old Tennessee Walking Horse gelding was presented for diagnosis of the cause of extensive alopecia. Complete hair loss was noted over the head, neck, shoulder, thigh, and proximal limbs, but the trunk, distal limbs, pelvic area, mane, and tail were unaffected. The alopecic areas were visually noninflammatory with no exudate or crust except on the shoulder and along the back, where multifocal patchy areas of alopecia with scales and crust were evident. The horse was slightly pruritic. Microscopically, the hair bulbs, inner and outer root sheaths of inferior segments, and perifollicular...
Sonmez K, Gurel A, Takai S.The aim of the present study was to develop an immunocytochemical procedure for the early detection and demonstration of Rhodococcus equi in smears of tracheal aspirates taken from live foals in field conditions. Tracheal wash samples were collected from thoroughbred foals, aged 1-5 months and located in studs around Bursa and Istanbul, Turkey. Some foals were suspected of having R. equi infection on the basis of clinical examination (n=56) and others were unaffected control animals (n=54). Serum samples were also collected from each foal for testing for the presence of R. equi-specific antibo...
Ryan PL, Christiansen DL, Hopper RM, Walters FK, Moulton K, Curbelo J, Greene JM, Willard ST.Uterine and placental infections are the leading cause of abortion, stillbirth, and preterm delivery in the mare. Whereas uterine and placental infections in women have been studied extensively, a comprehensive examination of the pathogenic processes leading to this unsatisfactory pregnancy outcome in the mare has yet to be completed. Most information in the literature relating to late-term pregnancy loss in mares is based on retrospective studies of clinical cases submitted for necropsy. Here we report the development and application of a novel approach, whereby transgenically modified bacter...
Castillo-Olivares J, Mansfield KL, Phipps LP, Johnson N, Tearle J, Fooks AR.West Nile virus (WNV) has re-emerged as an important pathogen for humans and horses, which are considered to be incidental 'dead-end' hosts. We have demonstrated that horses are susceptible to experimental infection with WNV and that horses infected with either WNV lineage 1 or lineage 2 elicit a similar antibody profile in serum samples. These data suggest that virus-neutralizing antibody responses persist for longer than WNV-specific IgM levels in serum and that there are not any notable differences in the antibody profile following experimental infection of horses with either WNV lineage 1 ...
Lengacher B, Kline TR, Harpster L, Williams ML, Lejeune JT.Manure from draft animals deposited in fields during vegetable and fruit production may serve as a potential source of preharvest pathogen contamination of foods. To better quantify this risk, we determined the prevalence of Escherichia coli O157:H7 in horses. Between June and September 2009, freshly voided fecal samples were collected from horses stabled on 242 separate premises in Ohio, USA. Overall, the prevalence of E. coli O157:H7 was 1 of 242 (0.4% prevalence, 95% confidence interval [CI] = 0.01 to 2.28). E. coli O157:H7 was recovered from none of the 107 equine fecal samples (0% prevale...
Shimojima M, Nagao Y, Shimoda H, Tamaru S, Yamanaka T, Matsumura T, Kondo T, Maeda K.In the past 25 years, there has been only one case of Japanese encephalitis in horses in Japan. We determined the full genome sequence of the Japanese encephalitis virus (JEV) strain JEV/eq/Tottori/2003 isolated from an afflicted horse and also analyzed its virulence in mice. The sequence analysis showed that the genome of JEV/eq/Tottori/2003 is similar to that of genotype I, a dominant genotype of JEV presently circulating in Japan. Its neurovirulence, but not neuroinvasiveness, was still as high as it was for genotype III, thus indicating the necessity for continuation of a vaccination progr...
Oue Y, Ishihara R, Edamatsu H, Morita Y, Yoshida M, Yoshima M, Hatama S, Murakami K, Kanno T.A new equine coronavirus was isolated from the feces of adult horses with pyrogenic and enteric disease. The disease outbreak was mainly observed among 2- to 4-year-old horses living in stables of a draft-horse racetrack in Japan. On comparing the isolated virus (isolate Tokachi09) with the equine coronavirus NC99 strain, no significant differences were observed in several biological properties such as hemagglutinating activity, antigenicity (in indirect immunofluorescence and neutralization tests), and one-step growth (in cell culture). The sequences of the nucleocapsid and spike genes of iso...
Mujica FF, Perrone T, Forlano M, Coronado A, Meléndez RD, Barrios N, Alvarez R, Granda F.The main objective of this study was to demonstrate the occurrence of equine piroplasmosis (EP) in horses of Lara State, Venezuela, and to correlate it with the factors host's sex and age in order to know the epidemiology of this disease at the Venezuelan Centroccidental Region. Antibody levels to Babesia caballi and Theileria equi were assessed in 360 equine serum samples, collected from 9 municipalities of Lara State, using an ELISA technique with recombinant antigens and monoclonal antibodies (Mabs). Antibodies to B. caballi were found in 254 horses (70.6%), whereas 181 animals (50.3%) were...
Sturgill TL, Giguère S, Franklin RP, Cohen ND, Hagen J, Kalyuzhny AE.The objectives of the present study were to determine if administration of inactivated parapoxvirus ovis (IPPVO) can decrease the cumulative incidence of pneumonia and increase the number of IFN-γ- and IL-4-secreting cells among foals. Fifty-nine foals were randomly assigned to 2 treatment groups (IPPVO or placebo) prior to birth. At 24-48 h of age, foals received 2 ml of either IPPVO or a placebo by intramuscular injection. Injections were repeated 24h and 8 days later. The number of IFN-γ- and IL-4-secreting cells was measured using a validated ELISPOT assay on blood mononuclear cells coll...
Kuskie KR, Smith JL, Wang N, Carter CN, Chaffin MK, Slovis NM, Stepusin RS, Cattoi AE, Takai S, Cohen ND.To determine whether airborne concentrations of virulent Rhodococcus equi at 2 horse breeding farms varied on the basis of location, time of day, and month. Methods: 2 farms in central Kentucky with recurrent R equi-induced pneumonia in foals. Methods: From February through July 2008, air samples were collected hourly for a 24-hour period each month from stalls and paddocks used to house mares and their foals. Concentrations of airborne virulent R equi were determined via a modified colony immunoblot technique. Differences were compared by use of zero-inflated negative binomial methods to dete...
Diaz-Mendez A, Viel L, Hewson J, Doig P, Carman S, Chambers T, Tiwari A, Dewey C.The objective of this project was to develop and implement an active surveillance program for the early and rapid detection of equine influenza viruses in Ontario. For this purpose, from October 2003 to October 2005, nasopharyngeal swabs and acute and convalescent serum samples were collected from 115 client-owned horses in 23 outbreaks of respiratory disease in Ontario. Sera were paired and tested for antibody to equine influenza 1 (AE1-H7N7), equine influenza 2 (AE2-H3N8), equine herpesvirus 1 and 4 (EHV1 and EHV4), and equine rhinitis A and B (ERAV and ERBV). Overall, the cause-specific mor...
Zoonoses and public healthJanuary 5, 2011
Volume 58, Issue 6 416-423 doi: 10.1111/j.1863-2378.2010.01382.x
Toledo RS, Tamekuni K, Filho MF, Haydu VB, Barbieri AR, Hiltel AC, Pacheco RC, Labruna MB, Dumler JS, Vidotto O.Spotted fever is a disease caused by bacteria from the genus Rickettsia of the spotted fever group (SFG). Rickettsia rickettsii is likely the main agent of Brazilian spotted fever (BSF). With the objective of gathering information on the circulation of SFG rickettsiae in Londrina, Parana state, ticks from dogs and horses and also blood from dogs, horses and humans were collected in a neighbourhood of the city which presented potential for circulation of rickettsiae between hosts and vectors. Amblyomma cajennense, Dermacentor nitens, and Rhipicephalus sanguineus ticks were subjected to Polymera...
Ledbetter EC, Irby NL, Kim SG.To describe in vivo corneal confocal microscopy of horses with fungal keratitis and correlate findings with clinical, histopathological, and microbiological evaluations of clinical cases and an ex vivo experimental equine fungal keratitis model. Methods: A total of 12 horses with naturally-acquired fungal keratitis and ex vivo equine corneas experimentally infected with clinical fungal isolates. Methods: Horses with naturally-acquired fungal keratitis were examined with a modified Heidelberg Retina Tomograph II and Rostock Cornea Module. Confocal microscopy images of clinical isolates of Asper...
Szczerba-Turek A, Siemionek J, Bancerz-Kisiel A, Raś A, Szweda W.The aim of the study was to analyse a part of the sequence of the E5 gene of bovine papillomaviruses (BPV) associated with equine sarcoids in Polish horses. Samples of 40 skin lesions obtained from 29 horses were collected for molecular examination. The PCR amplicons of BPV DNA were detected in 38 specimens. After phylogenetic analysis 37 specimens were recognized as BPV-1 and one as BPV-2. Phylogenetic analysis has allowed the classification of the amplicons into two phylogenetic groups (A1,) and four separate isolates (2, 10, 16, 17).
Murray KO, Mertens E, Despres P.Zoonotic West Nile virus (WNV) circulates in natural transmission cycles involving certain mosquitoes and birds, horses, humans, and a range of other vertebrates are incidental hosts. Clinical infections in humans can range in severity from uncomplicated WNV fever to fatal meningoencephalitis. Since its introduction to the Western Hemisphere in 1999, WNV had spread across North America, Central and South America and the Caribbean, although the vast majority of severe human cases have occurred in the United States of America (USA) and Canada. By 2002-2003, the WNV outbreaks have involved thousa...
Aalsburg AM, Erdman MM.Taylorella equigenitalis is the etiologic agent of contagious equine metritis (CEM), a venereal disease of horses. A total of 82 strains of T. equigenitalis isolated in the United States were analyzed by pulsed-field gel electrophoresis (PFGE) after digestion of genomic DNA with restriction enzyme ApaI. Twenty-eight of those strains isolated from horses in the 2009 U.S. outbreak (CEM09) were further analyzed with NotI and NaeI enzymes. When ApaI alone was used for analysis, the 82 isolates clustered into 15 different genotypes that clearly defined groups of horses with known epidemiological co...
Sevá Ada P, Funada MR, Souza Sde O, Nava A, Richtzenhain LJ, Soares RM.The aim of this study was to assess the occurrence of Cryptosporidium in domestic animals in rural properties surrounding rain forest fragments within the municipality of Teodoro Sampaio, southeastern Brazil. Conventional sucrose flotation method followed by molecular characterization of the parasites by sequencing PCR products amplified from SSU rRNA gene were used. Stool samples were collected from domestic animals raised as pets and livestock in all rural properties surrounding three forest fragments. Samples from cattle (197), equine (63), pigs (25), sheep (11), and dogs (28) were collecte...
Tamekuni K, Toledo Rdos S, Silva Filho Mde F, Haydu VB, Pacheco RC, Cavicchioli JH, Labruna MB, Dumler JS, Vidotto O.Brazilian spotted fever (BSF) is an emerging disease most likely caused by Rickettsia rickettsii. The objective of the present study was to estimate the seroprevalence of BSF rickettsia infections in equines from six horse farms located in Londrina County, Paraná, Southern Brazil. Six owners of horse farms situated in Cambé, Santa Fé, Guaraci and Londrina municipalities participated in the study. All farms were located in areas where BSF has not been reported. A total of 273 horses were sampled and their sera were tested by indirect immunofluorescence assay (IFA) using R. rickettsii and R. ...
Baldani CD, Nakaghi AC, Machado RZ.Blood and serum samples from 170 horses raised in the Jaboticabal microregion, São Paulo State, Brazil, were collected and tested by microscopic examination of blood smears, indirect fluorescent antibody test (IFAT) and nested polymerase chain reaction (nPCR) for Theileria equi infections. The association among the test results was verified by the McNemar test. During the examination of thin blood smears, parasites were detected in six (3.52%) horses. Anti-T. equi antibodies were detected in 100% sera samples, with titers ranging between 1:80 and 1:5120. The nPCR based on the T. equi merozoit...
Tolesano-Pascoli GV, Torga K, Franchin AG, Ogrzewalska M, Gerardi M, Olegário MM, Labruna MB, Szabó MP, Marçal Júnior O.This is a report of tick species, parasite prevalence and infestation intensity of birds in a forest fragment (18° 56' 57'' S and 48° 12' 14'' W) within the Brazilian cerrado (savanna), in the municipality of Uberlândia, State of Minas Gerais, Brazil. A total of 162 birds from 26 species were captured. One adult tick, 296 larvae and 67 nymphs were found on passerine birds. Of these, it was identified 31 larvae and 27 nymphs of Amblyomma longirostre, 17 nymphs of A. nodosum, one A. cajennense larvae and one male of Rhipicephalus sanguineus. All other ticks were identified as Amblyomma sp. la...
Botton SA, Pereira DI, Costa MM, Azevedo MI, Argenta JS, Jesus FP, Alves SH, Santurio JM.Pythium insidiosum is a fungus-like organism present in subtropical and tropical areas, such as Brazil, known to infect humans and various animal species. P. insidiosum is the etiological agent of pythiosis, an emerging and granulomatous disease characterized mainly by cutaneous and subcutaneous lesions in horses, the principal species affected. Accurate diagnosis of pythiosis and identification of its causal agent by microbiological and serological tests can be often difficult and inconclusive principally for horses and humans. The aim of this study was to evaluate the application of the prev...
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...
Dicken M, Munday JS, Archer RM, Mayhew IG, Pandey SK.Equine cutaneous fungal granulomas have been previously referred to in New Zealand (Fairley 1998), and are described in the veterinary literature from around the world, including North America and Australia (Pascoe and Summers 1981; Genovese et al. 2001; Valentine et al. 2006), but no peer-reviewed reports appear published in the literature in New Zealand. Described here is a case of multiple cutaneous fungal granulomas caused by Alternaria spp. in a horse in New Zealand.
Furr M, Howe D, Reed S, Yeargan M.Diagnosis of equine protozoal myeloencephalitis (EPM) remains a challenge for equine practitioners. Current utilized methods have inadequate sensitivity and specificity, because of a high number of false positive results. Objective: Evaluation of antibody indices to Sarcocystis neurona should provide high sensitivity and specificity for diagnosis of EPM. Methods: Archived samples from 29 clinical patients. Methods: Archived serum and cerebrospinal fluid (CSF) samples from clinical patients with either EPM (14) or cervical vertebral compressive myelopathy (CVM) (15) were examined and tested for...
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...
Weese JS.Methicillin-resistant Staphylococcus aureus (MRSA) is a critically important human pathogen that is also an emerging concern in veterinary medicine and animal agriculture. It is present in a wide range of animal species, including dogs, cats, rabbits, horses, cattle, pigs, poultry, and exotic species, both as a cause of infection and in healthy carriers. Identification of MRSA in various species and in food has led to concerns about the roles of animals, both pets and livestock, in the epidemiology of MRSA infection and colonization in humans. There is evidence of the role of food animals in h...
Bannai H, Tsujimura K, Kondo T, Nemoto M, Yamanaka T, Sugiura T, Maeda K, Matsumura T.An immunoglobulin G (IgG) subclass response against equine herpesvirus type 1 (EHV-1) infection was investigated in horses that were naïve to EHV-1/4 and those that had previously been exposed to EHV-4. The IgG subclass response was determined by an ELISA using EHV-1-specific recombinant gG protein as an antigen. In most horses naïve to EHV-1/4, IgGa, IgGb, and IgG(T) were induced after experimental infection with EHV-1. In contrast, a subclass response dominated by IgGa and IgGb, with no apparent increase in IgG(T), was observed after EHV-1 infection in horses previously infected with EHV-4...
Tenzin , Sharma B, Dhand NK, Timsina N, Ward MP.From January through July 2008, rabies reemerged in the Chhukha district of southwestern Bhutan. To clarify the distribution and direction of spread of this outbreak, we mapped reported cases and conducted directional tests (mean center and standard deviational ellipse). The outbreak resulted in the death of 97 animals (42 cattle, 52 dogs, and 3 horses). Antirabies vaccine was given free of charge to ≈674 persons suspected to have been exposed. The outbreak spread south to north and appeared to follow road networks, towns, and areas of high human density associated with a large, free-roaming...
Swayze RD, Bhogal HS, Barabé ND, McLaws LJ, Wu JQ.Western equine encephalitis virus (WEEV) is a mosquito-borne RNA virus which causes lethal infection in humans and equines. There are no commercial vaccines or anti-WEEV drugs available for humans. We used replication-defective, human adenovirus serotype-5 (HAd5) as a delivery vector for developing WEEV vaccine. Our previous study found delivery of both E1 and E2 envelope proteins of WEEV by HAd5 vector offers complete protection against lethal challenge of WEEV. In this paper, we constructed a HAd5-vectored E1 vaccine, Ad5-E1. Mice given single-dose vaccination of Ad5-E1 were completely prote...
Medina-Torres CE, Weese JS, Staempfli HR.Clostridium difficile infection (CDI) is a recognized cause of colitis in the horse. Identification of its toxins is important for management of individual cases and for prevention of transmission and zoonosis. In humans, CDI diagnosis is performed with enzyme immunoassays, none of which have been validated for horses. Objective: (1) Establish which test for CDI diagnosis was more frequently used by diagnostic laboratories, (2) determine the identified test's performance, sensitivity, and specificity, and (3) validate its use in diarrheic horses. Methods: Samples were obtained from 72 horses p...
Rivero LA, Concepción JL, Quintero-Troconis E, Quiñones W, Michels PA, Acosta H.Trypanosoma evansi is a monomorphic protist that can infect horses and other animal species of economic importance for man. Like the bloodstream form of the closely related species Trypanosoma brucei, T. evansi depends exclusively on glycolysis for its free-energy generation. In T. evansi as in other kinetoplastid organisms, the enzymes of the major part of the glycolytic pathway are present within organelles called glycosomes, which are authentic but specialized peroxisomes. Since T. evansi does not undergo stage-dependent differentiations, it occurs only as bloodstream forms, it has been ...
Songsri J, Kinoshita Y, Kwanhian W, Wisessombat S, Tangpong J, Rahman-Khan MS, Tuanyok A.The monoclonal antibody-based latex agglutination tests targeting a high molecular weight exopolysaccharide antigen of Burkholderia pseudomallei are commercially available. The tests are primarily used in routine diagnosis of melioidosis in major hospitals in Thailand and some endemic countries. Being a rapid test, this technique was employed as a presumptive test to identify colonies of B. pseudomallei among many others grown from soil specimens collected from southern Thailand. Cross-reactivity of these tests with other soil bacteria was a concern since it complicated the identification of B...
Ceylan O, Benedicto B, Ceylan C, Tumwebaze M, Galon EM, Liu M, Xuan X, Sevinc F.Common vector-borne diseases of horses include equine piroplasmosis (EP) caused by Babesia caballi and Theileria equi, and equine granulocytic anaplasmosis (EGA) caused by Anaplasma phagocytophilum. Equine piroplasmosis leads to severe health issues in horses and restrictions on the movement of horses internationally. Anaplasma phagocytophilum causes an acute febrile illness in horses and is also of zoonotic importance. In the present study, blood samples were collected from 152 Turkish racehorses from three different provinces (İzmir, Gaziantep, and Konya) of Turkey to investigate the preval...
Melnick JL, Hampil B.This paper summarizes the results of the fourth part of a comprehensive programme undertaken by the WHO International Reference Centre for Enteroviruses and other laboratories for the testing of enterovirus equine antisera prepared for long-term use as reference antisera. The studies were designed to appraise the specificity of the immune serum of horses inoculated with prototype enteroviruses (coxsackievirus types A2, 4, 8, 10, 11, 14-16, 18-21, and 24, and echoviruses E21, 27, 30, 31, and 33). Tests for neutralizing antibody were performed against the homologous viruses and against available...
Cummings KJ, Rodriguez-Rivera LD, Mitchell KJ, Hoelzer K, Wiedmann M, McDonough PL, Altier C, Warnick LD, Perkins GA.Nosocomial salmonellosis continues to pose an important threat to veterinary medical teaching hospitals. The objectives of this study were to describe an outbreak of salmonellosis caused by Salmonella enterica serovar Oranienburg within our hospital and to highlight its unique features, which can be used to help mitigate or prevent nosocomial outbreaks in the future. We retrospectively analyzed data from patients that were fecal culture-positive for Salmonella Oranienburg between January 1, 2006, and June 1, 2011, including historical, clinical, and pulsed-field gel electrophoresis (PFGE) data...
Ward CL, Wood JL, Houghton SB, Mumford JA, Chanter N.Seventy-three bacterial isolates from 65 horses with and without evidence of lower airway disease were identified to assess whether the association with disease was accounted for by a small or large number of species. Just over half (50.5 per cent were Actinobacillus equuli, 17.8 per cent were A suis-like, 11 per cent were Pasteurella pneumotropica, 8.2 per cent were A lignieresii, 6.8 per cent were P haemolytica and 5.5 per cent were P mairii. These results suggest that a range of Actinobacillus and Pasteurella species can be isolated from the lower airways of horses, with many of the isolate...
Oxburgh L, Hagström A.In this paper we describe the development of a nested RT-PCR assay for the rapid diagnosis and characterisation of influenza virus directly from clinical specimens. Viral RNA is extracted from nasal swabs by the guanidine thiocyanate extraction method, and subsequently reverse transcribed. The complementary DNA is then used as template in a nested PCR reaction. Primers designed for use in this assay are specific for three templates; (1) the nucleoprotein (NP) gene, (2) the haemagglutinin gene of the H7N7 equine influenza virus (A1), and (3) the haemagglutinin gene of the H3N8 equine influenza ...
Babenko VV, Millard A, Kulikov EE, Spasskaya NN, Letarova MA, Konanov DN, Belalov IS, Letarov AV.The viromes of the mammalian lower gut were shown to be heavily dominated by bacteriophages; however, only for humans were the composition and intervariability of the bacteriophage communities studied in depth. Here we present an ecogenomics survey of dsDNA bacteriophage diversity in the feces of horses (), comparing two groups of stabled horses, and a further group of feral horses that were isolated on an island. Our results indicate that the dsDNA viromes of the horse feces feature higher richness than in human viromes, with more even distribution of genotypes. No over-represented phage geno...
Zweygarth E, Just MC, De Waal DT.By means of an in vitro culture technique, 75 samples of horse blood were examined for Babesia equi, a causative agent of equine piroplasmosis. At the time of culture initiation, 15 samples were microscopically positive for B. equi, and this was subsequently confirmed by culture diagnosis. Sixty samples showed no parasites in Giemsa-stained thin blood smears. However, after the culturing process, parasites were found in blood smears of 36 of these samples. The sensitivity of the in vitro culture method was such that 2.5 microliters (1/40 of the usual volume used for the above-mentioned samples...
Gale P, Kelly L, Snary EL.The emergence of bluetongue virus and Schmallenberg virus in Great Britain (GB) during the last decade has highlighted the need for understanding the relative importance of the various pathways of the entry of livestock arboviruses so as to help focus surveillance and mitigation. This study summarizes what is known for the main routes of entry and assesses the strength of the current evidence for and against. Entry through infected arthropod vectors is considered at the level of each life cycle stage for tick-, biting midge- and mosquito-borne viruses, and while there is evidence that this cou...
Stobierski MG, Signs K, Dinh E, Cooley TM, Melotti J, Schalow M, Patterson JS, Bolin SR, Walker ED.Eastern equine encephalomyelitis (EEE) is a mosquito-borne viral disease that is an emerging public health concern in the state of Michigan. Although Michigan has one of the highest incidence rates of EEE in the United States, much of the information known about cases in humans, equines, and other animals residing in Michigan is unpublished. This article summarizes such information and explores spatial trends in the historic distribution of EEE in Michigan. Outbreaks in Michigan have occurred over an 80-yr interval, involving only horses in 1942-1943 and 1973-1976, and then episodically from 1...
Ito M, Itou T, Sakai T, Santos MF, Arai YT, Takasaki T, Kurane I, Ito FH.Brain samples from different animal species including humans: five vampire bats, 14 cattle, 12 dogs, 11 cats, two horses, one pig, one sheep and three humans collected from various geographical regions of Brazil were found to be positive for rabies by means of the fluorescent antibody test (FAT) and the mouse inoculation test (MIT). The brain samples were retested for rabies by means of the reverse transcription and polymerase chain reaction (RT-PCR) with 2 primer sets (P1/P2 and RHNI/RHNS3), which amplified full or partial regions on the nucleoprotein (N) gene of the rabies virus, respectivel...
El-Khatib AH, Engel AM, Weigel S.Hypoglycin A (HGA) and methylenecyclpropylglycine (MCPrG) are formed by some maple trees (Acer species) and have been associated with incidences of atypical myopathy among horses in pastures. In this work, a simple and sensitive ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method without derivatization was developed for the quantification of HGA and MCPrG in maple samples and validated according to EU guidelines. The LOQ presented here for HGA (16.4 µg/kg) is considerably lower than the lowest published LOQ (500 µg/kg). This method confirms that sycamore and ...
Charvat RA, Breitenbach JE, Ahn B, Zhang Y, O'Callaghan DJ.Defective interfering particles (DIP) of equine herpesvirus 1 (EHV-1) inhibit standard virus replication and mediate persistent infection. The DIP genome is comprised of only three genes: UL3, UL4, and a hybrid gene composed of portions of the IR4 (EICP22) and UL5 (EICP27) genes. The hybrid gene is important for DIP interference, but the function(s) of the UL3 and UL4 genes are unknown. Here, we show that UL4 is an early gene activated solely by the immediate early protein. The UL4 protein (UL4P) was detected at 4hours post-infection, was localized throughout the nucleus and cytoplasm, and was...
Barone A, Benktander J, Whiddon C, Jin C, Galli C, Teneberg S, Breimer ME.Pericardial tissue from various animal species is utilized for the production of the bioprosthetic heart valves (BHV) used clinically. Experimental data show that the eventual breakdown of BHV is partly due to immunological interactions with carbohydrate tissue antigens. To understand these processes, we have examined the glycolipid-based carbohydrate antigens in naïve porcine, bovine, and equine pericardia. Total non-acid and acid glycosphingolipid fractions were isolated from porcine, bovine, and equine pericardia, and individual glycolipid compounds were characterized by thin-layer chromat...
Mittelholzer C, Stadejek T, Johansson I, Baule C, Ciabatti I, Hannant D, Paton D, Autorino GL, Nowotny N, Belák S.To determine a conclusive phylogeny, equine arteritis viruses from Italy, Austria, Hungary, Sweden, South Africa and other parts of the world were analysed by reverse-transcription polymerase chain reaction amplification and direct sequencing. The nucleotide sequences corresponding to the variable part of the large glycoprotein GP5, specified by open reading frame 5, were compared and added to a previously published phylogenetic tree in which a clear division between 'European' and 'American' type viruses had been established. Adding the sequences determined in this study and new sequences ret...
Bhoora RV, Pienaar R, Cornelius F, Josemans A, Matthee O, Marumo R, Troskie C, Mans BJ.Quantitative real-time PCR assays previously developed for the detection of Theileria equi and Babesia caballi, were combined in a single multiplex TaqMan qPCR platform for the simultaneous detection of both heamoprotozoan parasites in equids. The multiplex equine piroplasmosis (M-EP) qPCR assay was shown to be efficient and specific. The detection limit was determined to be 1.4 × 10 % parasitized erythrocytes (PE) for T. equi and 2.8 × 10 % PE for B. caballi. The effect of differential DNA concentrations on the outcome of the M-EP qPCR for each target species was also investigated. ...
Mariappan V, Vellasamy KM, Anpalagar RR, Lim YM, Zainal Abidin N, Subramaniam S, Nathan S.The One Health concept was initiated to promote the integration of human, animal, and environmental ecosystems into healthcare to ensure effective control and the sustainable governance of multifaceted health matters. Climate change, deforestation, and rigorous farming disrupt the environment, which serves as the natural habitat for many animals and microbes, increasing the likelihood of disease transmission between humans and animals. Melioidosis (neglected tropical diseases) and glanders are of humans and animals caused by the gram-negative bacteria Burkholderia pseudomallei and its close re...
Du J, Wang X, Ma J, Wang J, Qin Y, Zhu C, Liu F, Shao Y, Zhou J, Qiao W, Liu X.The equine infectious anemia virus (EIAV) is a lentivirus of the Retrovirus family, which causes persistent infection in horses often characterized by recurrent episodes of high fever. It has a similar morphology and life cycle to the human immunodeficiency virus (HIV). Its transmembrane glycoprotein, gp45 (analogous to gp41 in HIV), mediates membrane fusion during the infection. However, the post-fusion conformation of EIAV gp45 has not yet been determined. EIAV is the first member of the lentiviruses for which an effective vaccine has been successfully developed. The attenuated vaccine strai...
Current HIV researchMarch 10, 2010
Volume 8, Issue 1 66-72 doi: 10.2174/157016210790416352
Payne SL, Fuller FJ.Equine infectious anemia virus (EIAV) is a macrophage-tropic lentivirus that rapidly Induces disease in experimentally infected horses. Because EIAV infection and replication is centered on the monocyte/macrophage and has a pronounced acute disease stage, it is a useful model system for understanding the contribution of monocyte/macrophages to other lentivirus-induced diseases. Genetic mapping studies utilizing chimeric proviruses in which parental viruses are acutely virulent or avirulent have allowed the identification of important regions that influence acute virulence. U3 regions in the vi...
Miranda J, Mattar S.Anaplasma and Ehrlichia species are important tick-borne pathogens that cause disease in cattle, dogs, horses and humans; with little information available about these agents in Colombia. The aim of this study was to provide molecular evidence for the presence of Anaplasma sp. and Ehrlichia sp. species in ticks collected from horses, dogs and cattle in Cordoba, Colombia. In this study, 1.105 ticks were removed from 226 zebu cattle (Bos indicus), 87 dogs (Canis lupus familiaris) and 19 horses (Equus caballus), from different localities of Cordoba. Ticks were identified taxonomically and PCR ass...
Calvert AE, Bennett SL, Hunt AR, Fong RH, Doranz BJ, Roehrig JT, Blair CD.Eastern equine encephalitis virus (EEEV), western equine encephalitis virus (WEEV) and Venezuelan equine encephalitis virus (VEEV) can cause fatal encephalitis in humans and equids. Some MAbs to the E1 glycoprotein are known to be cross-reactive, weakly neutralizing in vitro but can protect from disease in animal models. We investigated the mechanism of neutralization of VEEV infection by the broadly cross-reactive E1-specific MAb 1A4B-6. 1A4B-6 protected 3-week-old Swiss Webster mice prophylactically from lethal VEEV challenge. Likewise, 1A4B-6 inhibited virus growth in vitro at a pre-attachm...
Duncan C, Bartlett KH, Lester S, Bobsien B, Campbell J, Stephen C, Raverty S.In the last decade Cryptococcus gattii has emerged as an important human and animal pathogen in southwestern British Columbia (BC), Canada. When the disease initially emerged it was identified in humans and multiple animal species on the east coast of Vancouver Island. From fall 2003 until summer 2004, active surveillance was initiated to look for horses exposed to or infected with the organism by performing nasal cultures and serum antigen testing in horses residing within 10 km of known areas of environmental reservoirs of the fungus. Surveillance efforts were facilitated by local equine pra...
Lee J, Park JH, Min JY.The non-structural protein of influenza A virus (NS1A protein) is a multifunctional protein that antagonizes host antiviral responses and contributes to efficient viral replication during infection. However, most of its functions have been elucidated by generating recombinant viruses expressing mutated NS1 proteins that do not exist in nature. Recently, the novel H3N8 A/Equine/Kyonggi/SA1/2011 (KG11) influenza virus was isolated in Korea from horses showing respiratory disease symptoms. KG11 virus contains a naturally truncated NS gene segment with the truncation in the NS1A coding region, res...
Kumar S, Sudan V, Shanker D, Devi A.Equine piroplasmosis, caused by Babesia (Theileria) equi, is well reported from many parts of India. However, literature regarding its prevalence from semi arid India is limited. Alongside, there is complete absence of information about genetic characterization of B.(T.) equi and the associated genotypes from India. In the present study, the prevalence of B.(T.) equi was studied from semi arid India using 18S ribosomal gene based PCR assay. An overall prevalence rate of 10.46% was recorded. PCR was more sensitive and specific in comparison with blood smears. The found isolates were sequenced. ...
Hirata H, Xuan X, Yokoyama N, Nishikawa Y, Fujisaki K, Suzuki N, Igarashi I.The efficacy of the Be82 gene product fused with glutathione S-transferase (GST/Be82) in an enzyme-linked immunosorbent assay (ELISA) for the diagnosis of Babesia equi infection was reported previously (H. Hirata et al., J. Clin. Microbiol. 40:1470-1474, 2002). However, the ELISA with the GST/Be82 antigen cross-reacted with Babesia caballi-infected horse sera, despite the high rate of detection of B. equi. These results suggested that GST/Be82 has an antigen in common with B. caballi or antigenicity similar to that of B. caballi. In the present study, we constructed a series of five clones wit...
El-Hage C, Legione A, Devlin J, Hughes K, Jenkins C, Gilkerson J. is an important zoonotic pathogen. Although primarily a pathogen of birds, from which infection can spillover into humans and other mammalian hosts, the importance of as a cause of equine reproductive loss and the risk of infection to humans in contact with infected horses are increasingly being recognised in Australia and elsewhere. Despite the risks to both human and equine health, infection in horses is incompletely understood. This study aimed to update and summarise cases of equine psittacosis in Australia in the period 2018-2022, thus addressing a knowledge gap relating to recent case...
Xiao C, Liu Y, Jiang Y, Magoffin DE, Guo H, Xuan H, Wang G, Wang LF, Tu C.Four monoclonal antibodies (mAbs) were generated by immunizing BALB/C mice with recombinant nucleocapsid protein (N) of Nipah virus (NiV) and Hendra virus (HeV) expressed in E. coli. Two mAbs each were obtained for the HeV N and NiV N, respectively. All four mAbs displayed specific reactivity with the recombinant N proteins of both viruses by western blot, which was further confirmed by immunofluorescent antibody assay using fixed insect cells infected with recombinant baculoviruses expressing either the HeV or NiV N protein. Epitope mapping using a 12-mer random peptide phage display library ...
Tirosh-Levy S, Gottlieb Y, Steinman A.Stress has been suggested as a risk factor for Theileria equi peracute disease and may lead to relapse in clinical signs in chronically infected horses. The aim of this study was to assess the effect of stress on T. equi parasitemia in sub-clinically infected horses in two settings: horses hospitalized at a veterinary teaching hospital and horses from an endurance farm. Blood samples were collected from the hospitalized horses (n = 32) upon admission (T0) and at discharge (T1) from the hospital, and results were compared between horses that underwent surgery (stress) and other hospitalized...
