Infections in horses encompass a range of diseases caused by various pathogens, including bacteria, viruses, fungi, and parasites. These infections can affect different systems within the horse, such as the respiratory, gastrointestinal, and integumentary systems, leading to a variety of clinical signs depending on the pathogen and the severity of the infection. Common infectious diseases in horses include equine influenza, strangles, and equine herpesvirus. Diagnosis often involves clinical examination, laboratory testing, and sometimes imaging, to identify the causative agent and assess the extent of the disease. Treatment strategies may include antimicrobial therapy, supportive care, and preventive measures such as vaccination and biosecurity practices. This page aggregates peer-reviewed research studies and scholarly articles that explore the pathogenesis, diagnosis, treatment, and prevention of infectious diseases in equine populations.
Whitlock F, Newton R, King S, Ionescu AM, Higgins S.With the geographical distribution of West Nile virus expanding, there is growing concern about the potential for an incursion to the UK. Here, Fleur Whitlock, Richard Newton, Simon King, Andra-Maria Ionescu and Sara Higgins provide a timely reminder of key aspects of the virus' biology.
Cabaret J.Resistance to anthelmintics in gastrointestinal nematodes (GINs) is highly prevalent, as these parasites have been treated with anthelmintics for decades in ruminants and horses. Anthelmintics belong to different classes, each with a different mode of action. The most used are benzimidazoles and macrocyclic lactones and, to a lesser extent, levamisole and pyrantel in herbivores, as estimated from the literature. Combining these classes should be effective in controlling GIN. However, several farmers' practices tend to promote GIN resistance. Therefore, it is unclear whether the use of anthelmi...
Falsini A, Coppola C, Fiori A, Buonavoglia D, Marchi S, Montomoli E, Pellegrini F, Lanave G, Martella V, Camero M, Trombetta CM.Influenza D virus (IDV), belonging to the family, was first discovered in 2011 in pigs. Surveys in humans and animals have been carried out to decipher IDV ecology. In this seroepidemiological study, we investigated the circulation of IDV lineages across Italy in livestock and wildlife animals. A total of 1038 animal serum samples (from 246 bovines, 249 swine, 98 equines, and 445 wild boars) were tested using hemagglutination inhibition and virus neutralization assays. The results confirm bovines as the primary reservoir for IDV, with high seroprevalence for both D/660 (87%) and D/OK (80%) st...
Poci Palumbo MI, Maciel Cavalcante R, Martins Amorim R, De Vasconcelos Machado VM, Sousa Rocha N, Garcia Ribeiro M, Cagnini DQ, Secorun Borges A.Bacterial infection of the equine central nervous system is rare. This report describes the clinical features, computed tomography (CT) findings, and postmortem results of a 3-month-old female Quarter Horse with an intracranial abscess. Clinical signs included seizures, depression, and bilateral blindness. CT imaging demonstrated a large space-occupying lesion in the left cerebral hemisphere, associated with a frontal bone fracture. Necropsy and histopathology confirmed the presence of an abscess secondary to head trauma. Bacterial culture identified Streptococcus equi subsp. zooepidemicus as...
Hardefeldt L, Thomas K, Page S, Norris J, Browning G, El Hage C, Stewart A, Gilkerson J, Muscatello G, Verwilghen D, van Galen G, Bauquier J....The growing problem of antimicrobial resistance also affects equine veterinarians with increasing frequency. Antimicrobial stewardship and responsible prescribing are essential for a future in which effective antimicrobials are available, as it is unlikely that new antimicrobials will become available for use in horses. While antimicrobials are commonly used to treat equine infections, complications with therapy are also relatively common. Antimicrobial-associated diarrhoea, immune-mediated diseases, and nephrotoxicity have been reported as sequelae of antimicrobial therapy in equine practice....
Mughal MAS, Khan MK, Lan H, Abbas RZ, Imran M, Abbas Z, Mehmood MS, Ali S.Parasitic diseases caused by Leishmania spp. create considerable health concerns in animals, resulting in a considerable financial impact. They causes a complex infection in equines, affecting weight gain, skin, liver, and spleen. To date, there is a lack of reports on the occurrence of Leishmania in equines in Southern Punjab, Pakistan, highlighting the need for molecular epidemiological surveillance. The current study focused on determining the prevalence of Leishmania in the equine population from District Rahim Yar Khan, Southern Punjab, Pakistan, through amplification of mitochondrial (Cy...
Azócar-Aedo L, Meniconi G, Pino-Olguín C, Gallardo M.At a veterinary hospital in southern Chile, we conducted an epidemiological study involving domestic dogs, cats, and horses to determine the seropositivity for pathogenic spp., identify the infecting serogroups, measure antibody titers, and characterize seropositive animals by sex and age. None of the sampled animals showed clinical signs of leptospirosis. The microscopic agglutination test, using a panel of eight serogroups, was used for diagnosis. The seropositivity was 36.5% (95% confidence interval [CI] = 24.5-48.4) in dogs, 12.9% (95% CI = 2.6-23.1) in cats, and 45.2% (95% CI = 30.1-60.2...
Samuels AN, Collins NM, Hanlon K, Bartish C, Kelly P, Kamr AM, Toribio RE.Early and accurate identification of septicemia in neonatal foals improves survival. In human medicine, the neutrophil-to-lymphocyte ratio (NLR), neutrophil-to-monocyte ratio (NMR), monocyte-to-lymphocyte ratio (MLR), and plasma cell-free DNA (cfDNA) aid in early bacteremia detection. This study evaluated the diagnostic utility of these markers in conjunction with other clinical and hematological parameters in hospitalized foals < 5 days old to predict positive blood culture at admission and to distinguish between Gram-positive, Gram-negative, or polymicrobial bacteremia. A total of 391 foal...
Uprety T, Durazo J, Paul L, Metiner K, Ruby R, Loynachan A, Janes J, Kenndy L, Cassone L, Molly E, Quick M, Morgan J, Beyhan S, Erol E.Neorickettsia risticii (N. risticii) is an obligatory intracellular bacterium that causes Potomac horse fever (PHF), a disease clinically characterized by diarrhea, pyrexia, and laminitis in horses. Although sporadic reports of N. risticii infection have been linked to abortion in mares, a detailed retrospective study, including genomic analysis of the pathogen from an aborted fetus, has not been published. This study examined 546 fecal samples from clinically ill horses (January 1, 2017-December 31, 2024) and 833 colon samples from aborted equine fetuses (September 20, 2018-December 31, 2024)...
Kronenberg PA, Fouché N, Sekiya M, Liechti P, Frey CF, Mulcahy G, Eichenberger RM.Fasciola hepatica is a common trematode parasite of livestock in many regions, causing significant economic losses and affecting animal welfare. Horses rarely develop patent liver fluke infection. However, liver damage can affect animal health and welfare. Therefore, F. hepatica infection in horses may be underreported. Recently, a serological test for the antibody detection has been reported based on recombinant parasite cathepsin L1 (FhCL1) protease. Here, we optimized this enzyme-linked immunosorbent assay (ELISA) for antibody-detection in horses with equine fasciolosis based on recombinant...
Joó K, Csanádi L, Povázsai Á, Nielsen MK.Horses remain globally at constant risk of strongylid infections, with cyathostomins being particularly prevalent and abundant. It is essential to routinely monitor the efficacy of anthelmintics against equine nematodes. This study aimed to evaluate the efficacy of ivermectin against equine strongyles and estimate the strongyle egg reappearance period (ERP) following ivermectin treatment for the first time in Hungary. Fecal samples were collected from 57 Thoroughbred mares before treatment and at 2, 4, 5, 6, and 7 weeks post-treatment at a Hungarian National Stud Farm. Fecal egg counts (FECs)...
Alfatlawy HJ. in Arabian mares poses a significant reproductive challenge, necessitating proper pathogen identification and antimicrobial susceptibility determination. Unassigned: To investigate the prevalence of intrauterine pathogens and their antimicrobial susceptibility patterns in Arabian mares with postbreeding endometritis. Unassigned: Seventeen Arabian mares were examined clinically and ultrasonographically. Uterine swabs were collected for bacterial isolation and antimicrobial susceptibility testing. Unassigned: Clinical endometritis was detected in 29.4% of the mares. Ultrasonographic examination...
Ceriotti S, Clark-Price S, Cole R, Kramer A, Sandey M, Mora M.This case describes a 15-year-old Thoroughbred mare with fistulous withers that progressed to vertebral osteomyelitis and spinal epidural abscess (SEA), a severe complication that has yet to be reported. Initially treated with antibiotics and anti-inflammatory medication, the mare developed acute hindlimb ataxia and spastic paresis, suggesting spinal cord compression at T3-L3. Diagnostic imaging revealed vertebral fractures and abscessation, but vertebral canal involvement could not be confirmed. Despite aggressive medical therapy, including antimicrobials, corticosteroids, and neuroprotective...
Nemoto M, Kawanishi N, Kamei R, Furusho K, Kawauchi K, Yabuuchi Y, Oue Y, Uchida Y, Nishiura H, Reedy SE, Chambers TM, Li F, Bannai H, Yamanaka T....In April and May 2025, outbreaks of equine influenza occurred for the first time in 17 years in Japan. Equine influenza virus (EIV) of the H3N8 subtype was mainly detected in heavy draft horse populations in Kumamoto Prefecture and the Tokachi area of Hokkaido. In total, 10 EIVs were isolated from infected horses and then were used for genetic and serological analyses. Phylogenetic analysis of all eight genes revealed that all Japanese isolates were clustered with the Florida sublineage clade 1 (Fc1) viruses and were closely related to North American Fc1 viruses detected in 2024-2025. The resu...
Beshir A, Kemal J, Abraha B, Tola EH.Wounds on the skin are a common health issue affecting working equines. This study aimed to evaluate the in-vitro antibacterial properties of crude methanolic extracts from selected medicinal plants against pathogens isolated from equine skin wounds in Merti district. Agar well and disc diffusion tests were used to determine the mean zone of inhibition, while broth dilution methods were used to determine the minimum inhibitory concentrations and minimum bactericidal concentrations (MBCs), further confirming the potent antibacterial effects of the selected medicinal plant extracts. One way anal...
Modrý D, Hainisch EK, Fuehrer HP, Kniha E, Unterköfler MS, Sádlová J, Jahn P, Řeháková K, Sedlák K, Votýpka J.We report 4 cases of equine cutaneous leishmaniasis caused by Leishmania martiniquensis in Czech Republic and Austria, outside the known endemic range of leishmaniases. The parasite should be considered as a potential cause of cutaneous lesions in horses; the risk for zoonotic transmission to immunocompromised humans is anticipated throughout central Europe.
Şahinkesen İ, Bilge-Dağalp S.Equine herpesvirus 1 (EHV-1) and Equine herpesvirus 4 (EHV-4) are major viral pathogens of horses that contribute to respiratory disease, abortion, and neurological disorders, leading to economic losses in the equine industry. Accurate serological diagnosis is critical for disease surveillance and control. This study aimed to develop and validate an in-house enzyme-linked immunosorbent assay (ELISA) for detecting antibodies against EHV-1 and EHV-4 in horse sera. Serum samples previously confirmed by virus neutralization test (VNT) and a commercial ELISA were used to optimize the assay. Cut-off...
Hacilarlioglu S, Bilgic HB, Karagenc T, Aydin HB, Toker H, Kanlioglu H, Pekagirbas M, Bakirci S.Equine piroplasmosis (EP), caused by and , is a tick-borne disease posing significant threats to equine health and the horse industry worldwide. Other vector-borne blood parasites, including , spp., and spp., can also infect horses; however, their prevalence remains poorly characterized in Türkiye. This study aimed to determine the molecular prevalence of , , , spp., and spp. in equids from the Western Aegean Region of Türkiye. Blood samples were collected from 388 clinically healthy equines across İzmir, Aydın, Denizli, and Muğla provinces. Species-specific PCR assays were performed...
Stasiak K, Dunowska M, Rola J.Equid herpesvirus 5 (EHV-5) comprises a group of heterogeneous viruses with a worldwide distribution. Primary infection typically occurs early in life, which is followed by latency and periodic recrudescence of the virus. The aim of this study was to determine the genetic variation of EHV-5 in individual animals over time and to determine the dynamics of EHV-5 spread among selected mare-foal pairs at three horse studs. The partial glycoprotein B () gene was amplified from archival nasal swab samples. Sequences from 3-5 clones from each PCR product were compared using identity matrix, phylogeny...
Chwirot A, Niedźwiedź A, Stygar D, Siwińska N, Paszkowska M, Niżański W, Napierkowska S, Migdał P, Kublicka A, Marynowska M, Matczuk A....This study investigated the presence of antibodies to human adenovirus type 36 (HAdV-D36) in horses with different metabolic statuses, including normal, overweight, and those diagnosed with equine metabolic syndrome (EMS). A total of 151 serum samples were tested, of which 47.6% were positive for anti-HAdV-D36 antibodies. Although the horses were confirmed to be susceptible to HAdV-D36 infection, there was no significant correlation between infection and blood glucose or cholesterol levels. However, the triglyceride levels showed significant differences-they were particularly elevated in the s...
Turcotte G, O'Sullivan TL, Rossi TM, Spence KL, Winder CB, Greer AL.Horses are frequently transported, creating opportunities for the spread of pathogens. Disease transmission models for equine infectious diseases face limitations on their generalizability due to challenges in describing equine movement and the structure of their contact networks beyond simplistic assumptions. This study aimed to combine a stochastic, agent-based, SEIR model for equine influenza disease dynamics with an observed Ontario, Canada equine contact network structure to quantify the potential magnitude of equine influenza outbreaks in Ontario competition horses under different condit...
Khan A, Jose-Cunilleras E, Hyde E, Olajide E, Polo MC, Goehring LS.Equid alphaherpesvirus 1 (EHV-1) remains a major concern for the equine industry, with recent outbreaks at international equestrian events highlighting the need for improved surveillance during competitions. Objective: To investigate EHV-1 and -4 presence in shared airspaces and environmental surfaces in direct contact with horses at international equestrian events; and to evaluate air sampling as a surveillance alternative to individual horse testing. Methods: Cross-sectional field study. Methods: Air (37) and surface samples (205) were collected from temporary stabling facilities across six ...
Vitale V, Bindi F, Bertelloni F, Sala G, Cingottini D, Bonelli F, Sgorbini M.Bacterial contamination of intravenous catheters in hospitalized horses may pose risks for both patient care and public health due to potential antimicrobial resistance and zoonotic transmission. This prospective clinical study aimed to evaluate the incidence of catheter contamination in equine patients admitted to a Veterinary Teaching Hospital between 2020 and 2021. All horses requiring intravenous catheterization were included, and data were collected on patient signalment, clinical status, duration of catheterization, treatments, and outcomes. Two catheter types were used: 5 cm polytetrafl...
Pereira EL, Pereira GR, Osório ML, Terra JLA, Gayger JB, Gularte JS, Demoliner M, Pereira VMAG, Filippi M, de Matos QS, Tessman A, Canal CW, Daudt C....Papillomaviruses (PV) are significant agents capable of inducing simple, multiple, and/or proliferative lesions in the dermis and epidermis of animals, known as cutaneous papillomatosis. These lesions can be benign or malignant and have been identified in various hosts, including mammals, birds, reptiles, and fish. PVs are strictly species- and tissue-specific, although some established and unusual cases of cross-infection, such as BPV in equine sarcoids, have been reported. Sarcoids are horses' most common skin tumors, which can be locally aggressive and cause significant clinical signs. It i...
Marchio SP, El-Sheikh Ali H, Scott MA, Barbosa Fernandes C, Scoggin KE, Troedsson M, Boakari Y.Despite its critical role in protecting the fetus, the amniotic membrane remains poorly understood in the context of disease response. The equine amniotic membrane is an important physical barrier to the amniotic compartment, and there is evidence that it may contribute to surfactant synthesis. Surfactants are essential for normal fetal lung development, and disruptions in its availability may be linked to future neonatal complications. Therefore, understanding the molecular changes that occur in fetal-maternal tissues during placentitis would clarify how this condition leads to abortion, pret...
Chinyere CN, Ajaebili AC, Peter-Ajuzie IK, Galadima HB, Daodu OB, Fatola OI, Okolo CC, Alaba BA, Akinniyi OO, Omoniwa DO, Edeh ER, Olorunfemi AB....African horse sickness (AHS) is a severe, infectious arthropod-borne disease of equids caused by the AHS virus (AHSV). It is endemic in Sub-Saharan Africa, and several sporadic outbreaks of the disease have been reported in Nigeria in the past 5 decades. Following a recent outbreak of the disease in Lagos State, this study was conducted to investigate the prevalence of (AHSV) antibodies in apparently healthy horses and some selected wildlife sampled in four geographical regions of Nigeria. Using a competitive enzyme-linked immunosorbent assay, 575 serum samples collected from horses in five ...
Mukhanbetkaliyev Y, Yessembekova G, Mukhanbetkaliyeva A, Akmambayeva B, Kadyrov A, Uskenov R, Bostanova S, Ashirbek A, Korennoy F, Abdrakhmanov S.Equine herpesvirus 1 (EHV-1) is one of the most dangerous viral diseases affecting ungulates, and is characterized by a wide range of clinical manifestations in horses, including rhinopneumonia, abortion, neonatal death, and myeloencephalopathy. It is well known for causing mass abortions in mares and respiratory diseases in young animals. Once introduced into a horse breeding farm of any type, EHV-1 tends to establish as a persistent infection. The disease is reported on nearly all continents and causes substantial annual economic losses to horse breeding operations. In Kazakhstan, 34 EHV-1 o...
Toda J, Miyasaka J, Osako H, Murata K, Yunus M, Amalia R, Soe BK, Sato H.Food poisoning caused by consuming raw horsemeat contaminated with Sarcocystis is a significant public health concern. Two morphotypes of sarcocysts in horsemeat, characterized by upright and folded villar protrusions, are typically identified as Sarcocystis fayeri and S. bertrami, respectively. However, recent molecular studies focusing on the ribosomal RNA gene (rDNA) and mitochondrial cytochrome c oxidase subunit I gene (cox1) have indicated a conspecific relationship between these two morphotypes using a limited number of specimens. To explore further genetic diversity in equid sarcocysts,...
Janshoff S, Plümers R, Ramsauer AS, Cavalleri J, Vollmer T, Todt D, Brown RJP, Steinmann E, Gömer A.The emergence of new pathogens poses a significant threat to global health, exacerbated by climate change, biodiversity loss, and increased globalization. Ticks, as vectors for various pathogens, contribute to the rising incidence of diseases. Surveillance programs are crucial for identifying and controlling emerging pathogens. This study focuses on the Alongshan virus (ALSV), a segmented flavi-like virus first identified in humans in China in 2017. Despite its ability to infect a wide range of mammals, the natural hosts and transmission pathways of ALSV remain poorly understood. Therefore, we...
Centers A, Barnaby K, Goedeker S, Pignataro A, Tretyakova I, Lukashevich I, Pushko P, Chung D.There is a need for safe and effective vaccines against the Venezuelan equine encephalitis virus that infects both humans and equines. However, development of a live-attenuated vaccine using the TC-83 strain has been hampered by substantial reactogenicity and the potential for neuroinvasion. In this study, we demonstrate that V4020, a new TC-83-based investigational VEEV vaccine with redundant safety features preventing neuroinvasion and reversion, exhibited no neuroinvasion potential in a murine model. Following subcutaneous or intramuscular administration, a subset of mice that received the ...
Takai S, Koike K, Ohbushi S, Izumi C, Tsubaki S.Antigens of Rhodococcus equi were analyzed by immunoblotting with naturally infected foal sera. Immunoblots of whole-cell antigen preparations of clinical isolates of R. equi revealed that major protein bands with molecular masses of 15 to 17 kDa were present in all clinical isolates tested and all isolates virulent for mice. In contrast, the 15- to 17-kDa antigens were not identified by immunoblotting in ATCC 6939, a type strain of R. equi that was avirulent for mice. Whole-cell antigens of 102 environmental isolates were investigated by immunoblotting and the mouse pathogenicity test. Twenty...
Field HE.Hendra virus causes acute and highly fatal infection in horses and humans. Pteropid bats (flying-foxes) are the natural host of the virus, with age and species being risk factors for infection. Urine is the primary route of excretion in flying-foxes, with viral RNA more frequently detected in Pteropus alecto and P. conspicillatus than other species. Infection prevalence in flying-foxes can vary between and within years, with a winter peak of excretion occurring in some regions. Vertical transmission and recrudescing infection has been reported in flying-foxes, but horizontal transmission is ev...
Cuny C, Strommenger B, Witte W, Stanek C.During 2006 and 2007 small clusters of methicillin-resistant Staphylococcus aureus (MRSA) infections in horses were recorded in different clinical departments of a veterinary university. The infections were caused by different MRSA clones (ST1, ST254, and ST398). In the same time, nasal colonization of veterinarians, veterinary personnel, and students was observed indicating transmission to humans.
Båverud V, Gustafsson A, Franklin A, Aspán A, Gunnarsson A.Clostridium difficile has been associated with acute colitis in mature horses. Objective: To survey C. difficile colonisation of the alimentary tract with age, occurrence of diarrhoea and history of antibiotic therapy; and to study the occurrence and survival of C. difficile in the environment and antimicrobial susceptibility of isolated strains. Methods: A total of 777 horses of different breeds, age and sex were studied. Further, 598 soil samples and 434 indoor surface samples were examined. Antimicrobial susceptibility of 52 strains was investigated by Etest for 10 antibiotics. Results: In ...
Leroux C, Issel CJ, Montelaro RC.We have investigated the genetic evolution of three functionally distinct regions of the equine infectious anemia virus (EIAV) genome (env, rev, and long terminal repeat) during recurring febrile episodes in a pony experimentally infected with a well-characterized reference biological clone designated EIAV(PV). Viral populations present in the plasma of an EIAV(PV)-infected pony during sequential febrile episodes (18, 34, 80, 106, and 337 days postinfection) were amplified from viral RNA, analyzed, and compared to the inoculated strain. The comparison of the viral quasispecies showed that the ...
Browning GF, Chalmers RM, Fitzgerald TA, Snodgrass DR.A group A rotavirus designated L338 was isolated from the faeces of a diarrhoeic foal and was compared to 11 standard G serotype strains of group A rotaviruses by cross-neutralization. It was clearly distinct from serotypes G1 to G11 and thus representative of a novel rotavirus G serotype tentatively designated G13. The nucleic acid sequence of the virion protein 7 (VP7) coding region was determined and the deduced amino acid sequence compared to published sequences. Within VP7 regions A and B, L338 was clearly distinct from serotypes G1 to G12 (excluding G7 which has not been sequenced), but ...
Van den Eede A, Martens A, Lipinska U, Struelens M, Deplano A, Denis O, Haesebrouck F, Gasthuys F, Hermans K.Methicillin-resistant Staphylococcus aureus (MRSA) infections do occur in equine patients. Little is known, however, about their origin and the general equine MRSA colonization status. In West European horses in particular, neither the colonization rate nor the present strains or their antimicrobial susceptibility patterns are known. In the present study, a sample of 110 (Belgian, French, Dutch and Luxemburg) horses presented at a Belgian equine clinic was screened for nasal MRSA carriage. An indirect culturing protocol using a 0.001% colistin and nalidixic acid containing broth was compared t...
Nemoto M, Bannai H, Tsujimura K, Kobayashi M, Kikuchi T, Yamanaka T, Kondo T.An outbreak of Getah virus infection occurred among racehorses in Japan during September and October 2014. Of 49 febrile horses tested by reverse transcription PCR, 25 were positive for Getah virus. Viruses detected in 2014 were phylogenetically different from the virus isolated in Japan in 1978.
Blitvich BJ, Bowen RA, Marlenee NL, Hall RA, Bunning ML, Beaty BJ.We evaluated the ability of epitope-blocking enzyme-linked immunosorbent assays (ELISAs) to detect West Nile virus (WNV) antibodies in domestic mammals. Sera were collected from experimentally infected horses, cats, and pigs at regular intervals and screened in ELISAs and plaque reduction neutralization tests. The diagnostic efficacies of these techniques were similar.
Vannella KM, Moore BB.Idiopathic pulmonary fibrosis (IPF) remains exactly that. The disease originates from an unknown cause, and little is known about the mechanisms of pathogenesis. While the disease is likely multi-factorial, evidence is accumulating to implicate viruses as co-factors (either as initiating or exacerbating agents) of fibrotic lung disease. This review summarizes the available clinical and experimental observations that form the basis for the hypothesis that viral infections may augment fibrotic responses. We review the data suggesting a link between hepatitis C virus, adenovirus, human cytomegalo...
de la Fuente J, Ayoubi P, Blouin EF, Almazán C, Naranjo V, Kocan KM.Anaplasma phagocytophilum (Rickettsiales: Anaplasmataceae) causes human, equine and canine granulocytic anaplasmosis and tick-borne fever of ruminants. The rickettsia parasitizes granulocytes and bone marrow progenitor cells, and can be propagated in human promyelocytic and tick cell lines. In this study, microarrays of synthetic polynucleotides of 21,329 human genes were used to identify genes that are differentially expressed in HL-60 human promyelocytic cells in response to infection with A. phagocytophilum. Semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) of selec...
Janvilisri T, Scaria J, Thompson AD, Nicholson A, Limbago BM, Arroyo LG, Songer JG, Gröhn YT, Chang YF.Clostridium difficile is a gram-positive, spore-forming enteric anaerobe which can infect humans and a wide variety of animal species. Recently, the incidence and severity of human C. difficile infection has markedly increased. In this study, we evaluated the genomic content of 73 C. difficile strains isolated from humans, horses, cattle, and pigs by comparative genomic hybridization with microarrays containing coding sequences from C. difficile strains 630 and QCD-32g58. The sequenced genome of C. difficile strain 630 was used as a reference to define a candidate core genome of C. difficile a...
Payne SL, Fang FD, Liu CP, Dhruva BR, Rwambo P, Issel CJ, Montelaro RC.The extent and nature of genomic variation among nine antigenically distinct EIAV isolates recovered during sequential clinical episodes from two experimentally infected ponies were examined by restriction fragment analysis and nucleotide sequencing. Only minor variations in restriction enzyme patterns were observed among the viral genomes. In contrast, env gene sequences of four isolates from one pony revealed numerous clustered base substitutions. Divergence in env gene nucleotide and deduced amino acid sequences between pairs of virus isolates ranged from 0.62 to 3.4% env gene mutation rate...
Hatam-Nahavandi K, Ahmadpour E, Carmena D, Spotin A, Bangoura B, Xiao L.Cryptosporidium spp. are causative agents of gastrointestinal diseases in a wide variety of vertebrate hosts. Mortality resulting from the disease is low in livestock, although severe cryptosporidiosis has been associated with fatality in young animals. Methods: The goal of this systematic review and meta-analysis was to review the prevalence and molecular data on Cryptosporidium infections in selected terrestrial domestic and wild ungulates of the families Bovidae (bison, buffalo, cattle, goat, impala, mouflon sheep, sheep, yak), Cervidae (red deer, roe deer, white-tailed deer), Camelidae (al...
Kay BH, Boyd AM, Ryan PA, Hall RA.Host feeding patterns of mosquitoes were assessed through the identification of 865 blood meals collected from Brisbane during 2000-2001. Under natural conditions, mosquito feeding (including that of Culex annulirostris, Aedes vigilax, and Aedes notoscriptus) was primarily on dogs (37.4%), but also on birds (18.4%), horses (16.8%), brushtail possums (13.3%), humans (11.6%), and cats, flying foxes, and macropods, depending on site. From 1997 to 1999, sera (N=1706) were collected from dogs, cats, horses, flying foxes, and brushtail possums in the Brisbane area and were analyzed by microneutraliz...
Webb K, Jolley KA, Mitchell Z, Robinson C, Newton JR, Maiden MCJ, Waller A.The zoonotic pathogen Streptococcus equi subsp. zooepidemicus (S. zooepidemicus) is commonly found harmlessly colonizing the equine nasopharynx. Occasionally, strains can invade host tissues or cross species barriers, and S. zooepidemicus is associated with numerous different diseases in a variety of hosts, including inflammatory airway disease and abortion in horses, pneumonia in dogs and meningitis in humans. A biovar of S. zooepidemicus, Streptococcus equi subsp. equi, is the causative agent of strangles, one of the most important infections of horses worldwide. We report here the developme...
Laatamna AE, Wagnerová P, Sak B, Květoňová D, Xiao L, Rost M, McEvoy J, Saadi AR, Aissi M, Kváč M.A total of 219 and 124 individual fecal samples of horses and donkeys, respectively, were screened for the presence of Cryptosporidium spp., Encephalitozoon spp., and Enterocytozoon bieneusi DNA by genus-specific nested PCR. Isolates were genotyped by sequence analysis of SSU rRNA, GP60, TRAP-C1, COWP, and HSP70 loci in Cryptosporidium, and the ITS region in microsporidia. Cryptosporidium spp. was detected on 3/18 horse farms and 1/15 farms where donkeys were kept. Overall, five (2.3%) horse and two (1.6%) donkey specimens were PCR positive for Cryptosporidium. Genotyping at SSU and GP60 loci ...
Edington N, Bridges CG, Patel JR.Eight mares were infected with equid herpesvirus-1 subtype 1 isolated from a case of equine paresis. In two mares killed at 4 d.p.i. immunofluorescence showed endothelial cell infection together with thrombosis in the rete arteriosus of the nasal mucosa and also in the spinal cord of one of these mares. Circulating platelet counts in the other six mares fell as early as 2 d.p.i. and remained depressed for seven days. Circulating immune complexes started to appear at 2 d.p.i., reached maximum levels at 10 d.p.i., but were undetectable at 28 d.p.i. Three of the six remaining mares developed vary...
Berglund AK, Schnabel LV.Allogeneic mesenchymal stem cells (MSCs) are a promising cell source for treating musculoskeletal injuries in horses. Controversy exists, however, over whether major histocompatibility complex (MHC)-mismatched MSCs are recognised by the recipient immune system and targeted for death by a cytotoxic antibody response. Objective: To determine if cytotoxic anti-MHC antibodies generated in vivo following MHC-mismatched MSC injections are capable of initiating complement-dependent cytotoxicity of MSCs. Methods: Experimental controlled study. Methods: Antisera previously collected at Days 0, 7, 14 an...
Science (New York, N.Y.)February 1, 1985
Volume 227, Issue 4686 522-524 doi: 10.1126/science.3880925
Holland CJ, Ristic M, Cole AI, Johnson P, Baker G, Goetz T.Potomac horse fever, a disease characterized by fever, anorexia, leukopenia, and occasional diarrhea, is fatal in approximately 30 percent of affected animals. The seasonal occurrence of the disease (June to October) and evidence of antibodies to the rickettsia Ehrlichia sennetsu in the serum of convalescing horses suggested that a related rickettsia might be the causative agent. Such an agent was isolated in cultured blood monocytes from an experimentally infected pony. This intracytoplasmic organism was adapted to growth in primary cultures of canine blood monocytes. A healthy pony inoculate...
Pusterla N, Mapes S, Wademan C, White A, Ball R, Sapp K, Burns P, Ormond C, Butterworth K, Bartol J, Magdesian KG.The purpose of this study was to describe clinical, hematological and fecal PCR results from 161 horses involved in outbreaks associated with ECoV. The outbreaks happened at four separate boarding facilities between November 2011 and April 2012 in the States of CA, TX, WI and MA. Following the molecular detection of ECoV in the feces from the initial index cases, the remaining herdmates were closely observed for the development of clinical signs. Fecal samples were collected from sick and healthy horses for the PCR detection of ECoV. All four outbreaks involved primarily adult horses. Fifty-ni...
Jacobsen S, Kjelgaard-Hansen M, Hagbard Petersen H, Jensen AL.The aim of the present study was to evaluate whether equine serum amyloid A (SAA) concentrations could be measured reliably with a turbidometric immunoassay (TIA) developed for use with human serum. Intra- and inter-assay imprecision were evaluated by multiple measurements on equine serum pools. Assay inaccuracy was determined by linearity under dilution. The assay was subsequently used for measuring SAA concentrations in clinically healthy horses, horses with inflammatory diseases, horses with non-inflammatory diseases, and in horses before and after castration. In pools with low, intermediat...
Riddle WT, LeBlanc MM, Stromberg AJ.Endometrial cytology and culture specimens (n=2123) were collected concurrently with a guarded uterine culture instrument from 970 mares (738 barren, 1230 foaling and 155 maiden mares) during three breeding seasons (2001-2004). Results were compared to the 28-d pregnancy rate for the cycle from which the samples were taken. Cytological smears were evaluated for inflammation at x100 and graded as: not inflammatory (0-2 neutrophils/field), moderate inflammation (2-5 neutrophils/field), severe inflammation (>5 neutrophils/field), or hypocellular (scant epithelial cells and no neutrophils). Ute...
Field H, Schaaf K, Kung N, Simon C, Waltisbuhl D, Hobert H, Moore F, Middleton D, Crook A, Smith G, Daniels P, Glanville R, Lovell D.To determine the epidemiologic and clinical features of a 2008 outbreak of Hendra virus infection in a veterinary clinic in Australia, we investigated the equine case-series. Four of 5 infected horses died, as did 1 of 2 infected staff members. Clinical manifestation in horses was predominantly neurologic. Preclinical transmission appears likely.
Ma G, Azab W, Osterrieder N.The equine herpesviruses type 1 (EHV-1) and 4 (EHV-4) are ubiquitous pathogens that affect horse populations on all continents. Despite widespread vaccination, EHV-1 and EHV-4 infections remain a permanent risk. While the two viruses share a high degree of genetic and antigenic similarity, they differ significantly in host range and pathogenicity. Compared to EHV-4, which mainly infects horses and causes respiratory disease, EHV-1 has a broader host range and can result in respiratory disease, abortions, neonatal death, and equine herpesvirusmyeloencephalopathy (EHM). Recent studies have eluci...
Meijer WG, Prescott JF.Rhodococcus equi is an important cause of subacute or chronic abscessating bronchopneumonia of foals up to 3-5 months of age. It shares the lipid-rich cell wall envelope characteristic of the mycolata, including Mycobacterium tuberculosis, as well as the ability of pathogenic members of this group to survive within macrophages. The possession of a large virulence plasmid in isolates recovered from pneumonic foals is crucial for virulence. The plasmid contains an 27 kb pathogenicity island (PI) that encodes seven related virulence-associated proteins (Vaps), including the immunodominant surface...
