Omneity® Pellets
All-In-One Vitamin & Mineral Pellet
Topic:Infectious Disease
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.
Equine encephalosis virus: evidence for circulation beyond southern Africa. Prior to the recent outbreak of equine encephalosis in Israel in 2009, equine encephalosis virus (EEV) had only been isolated from equids in South Africa. In this study we show the first evidence for the circulation of EEV beyond South Africa in Ethiopia, Ghana and The Gambia, indicating that EEV is likely to be freely circulating and endemic in East and West Africa. Sequence analysis revealed that the EEV isolate circulating in The Gambia was closely related to an EEV isolate that was isolated from a horse from Israel during the EEV outbreak in 2009, indicating that the two viruses have a com...
Seroprevalence of Toxoplasma gondii in domestic and wild animals from the Fernando de Noronha, Brazil. Fernando de Noronha is an archipelago of 21 islands and islets in the Atlantic Ocean, state of Pernambuco, Brazil, which has a varied biodiversity including alien species or sinantropic animals. The objective here was to determine the seroprevalence of Toxoplasma gondii in domestic and wild animals from Fernando de Noronha archipelago, Brazil. Between July 2007 and May 2010, blood samples were collected from 764 animals (533 domestic and 231 wild animals). Sera were tested by the indirect fluorescence antibody test (IFAT) or the modified agglutination test (MAT), or by both. Antibodies to T. g...
Hendra virus infection dynamics in Australian fruit bats. Hendra virus is a recently emerged zoonotic agent in Australia. Since first described in 1994, the virus has spilled from its wildlife reservoir (pteropid fruit bats, or 'flying foxes') on multiple occasions causing equine and human fatalities. We undertook a three-year longitudinal study to detect virus in the urine of free-living flying foxes (a putative route of excretion) to investigate Hendra virus infection dynamics. Pooled urine samples collected off plastic sheets placed beneath roosting flying foxes were screened for Hendra virus genome by quantitative RT-PCR, using a set of primers a...
Evaluation of the antiviral activity of (1’S,2’R)-9-[[1′,2′-bis(hydroxymethyl)cycloprop-1′-yl]methyl]guanine (A-5021) against equine herpesvirus type 1 in cell monolayers and equine nasal mucosal explants. Equine herpesvirus 1 (EHV1) is a ubiquitous equine alphaherpesvirus that causes respiratory disease, neurological symptoms and abortions. Current vaccines are not fully protective and effective therapeutics are lacking. A-5021 [(1'S,2'R)-9-[[1',2'-bis(hydroxymethyl)cycloprop-1'-yl]methyl]guanine], previously shown to possess potent anti-herpetic activity against most human herpesviruses, was evaluated for its potential to inhibit EHV1 replication. In equine embryonic lung (EEL) cells, infected with either a non-neurovirulent (97P70) or a neurovirulent (03P37) EHV1 isolate, A-5021 proved to be ...
Adaptation and validation of a bacteria-specific enzyme-linked immunosorbent assay for determination of farm-specific Lawsonia intracellularis seroprevalence in central Kentucky Thoroughbreds. Lawsonia intracellularis is the causative agent of equine proliferative enteropathy (EPE), a disease for which no large-scale seroprevalence studies have been conducted. Objective: To validate and use an equine-specific enzyme-linked immunosorbent assay (ELISA) for L. intracellularis to determine the seroprevalence of L. intracellularis on numerous farms. Methods: An ELISA, in which purified antigen was used, was adapted from previous work in swine. A total of 337 Thoroughbreds from 25 central Kentucky farms were enrolled and monthly serum samples collected from August 2010 to January/February...
Serosurveillance for Japanese encephalitis virus infection among equines in India. The seroprevalence of Japanese encephalitis virus (JEV) among equines was evaluated from January 2006 to December 2009 in 13 different states of India by hemagglutination inhibition (HI) test and virus neutralization test (VNT). Antibodies against JEV were detected in 327 out of 3,286 (10%) equines with a maximum prevalence reported in the state of Manipur (91.7%) followed by Gujarat (18.5%), Madhya Pradesh (14.4%), and Uttar Pradesh (11.6%). Evidence of JEV infection was observed in equines in Indore (Madhya Pradesh) where a 4-fold or higher rise in antibody titer was observed in 21 out of 34...
Quest for the piroplasms in camels: identification of Theileria equi and Babesia caballi in Jordanian dromedaries by PCR. DNA of two species of piroplasmids was detected in dromedaries during a survey of blood protozoans in Jordan between 2007 and 2009. Ten clinically healthy camels (10%) originating from three Jordanian districts were found, using a PCR assay, to harbor Theileria or Babesia species in their blood and no mix infection was determined. Analysis of the partial 18S rRNA gene sequences of these parasites allowed their unambiguous identification as equine piroplasmids Babesia caballi (n=6) and Theileria equi (n=4). In case of latter species, a novel genotype was found in horses. This first molecular-ba...
Molecular detection of Coxiella burnetii and Neospora caninum in equine aborted foetuses and neonates. Abortion, stillbirth and neonatal death are major causes of equine mortality and cause severe economic loss to the equine industry. The present study was based on a complete necropsy protocol associated with classical microbiological examinations and molecular biology on 407 cases of abortion, stillbirths and neonate death. Based on this retrospective survey, "less common" abortive infectious agents were characterised by molecular tools in nine independent cases of abortion or neonate mortality. Among others, Chlamydophila abortus (1 case), Coxiella burnetii (6 cases) and Neospora caninum (3 c...
ISCOM-matrix-based equine influenza (EIV) vaccine stimulates cell-mediated immunity in the horse. The humoral immune response induced by ISCOM-matrix (Immuno Stimulating COMplex-Matrix)-adjuvanted equine influenza virus (EIV) vaccine is well documented in horses. ISCOM-matrix adjuvanted vaccines against human influenza are strong inducers of cell-mediated immunity (CMI), including T cell proliferation and virus-specific cytotoxic T cell. In the horse, the CMI response to equine influenza vaccination is less well characterised. An ISCOM-based vaccine has been shown to induce interferon gamma (IFN-γ) synthesis, a CMI marker, in the horse, but this has not been shown for the ISCOM-matrix vac...
Contagious equine metritis eradicated from Japan. Contagious equine metritis (CEM), a contagious venereal disease of horses, invaded Japan in 1980 and spread in the Thoroughbred population of the Hidaka-Iburi district of Hokkaido. To eradicate CEM, we ran a program aimed at detecting Taylorella equigenitalis, the causal agent, in carrier horses by using the PCR test, followed by culling or treatment. In 2001, the first year of the program, 12,356 Thoroughbred racing stallions and mares were tested and 11 carriers were found. Four, two, one, and one carrier mares were detected in 2002, 2003, 2004, and 2005, respectively, by application of the ...
Lawsonia intracellularis-associated proliferative enteritis in weanling foals in the Netherlands. Equine proliferative enteropathy (EPE) is an emerging infectious enteric disease caused by the obligate intracellular gram-negative bacterium Lawsonia intracellularis. EPE was tentatively diagnosed in six weanling foals, aged between 5 and 7 months. Clinical signs included depression, anorexia, ventral oedema, and weight loss. Plasma biochemistry consistently revealed severe hypoproteinaemia. The ante-mortem diagnosis of EPE was based on clinical signs, hypoproteinaemia (6/6), the detection of moderate-to-high titres of L. intracellularis antibody (6/6), and severe thickening of the small inte...
Geographic structuring of global EIAV isolates: a single origin for New World strains? Equine infectious anaemia virus (EIAV) is classified within the Retroviridae and, like other lentivirus, has the propensity for considerable antigenic variation. An extensive phylogenetic analysis in Bayesian fashion, with significant amounts of new EIAV gag sequence information, revealed a strong geographic compartmentalization clearly related to the phylogeographic history of modern horses, pointing out that New World EIAV strains form a distinct group with a potentially common origin. This evidence suggests that a single founder event may have occurred during the reintroduction of horses to...
Seroprevalence of Toxoplasma gondii infection among horses in Tunisia. The present study was conducted to investigate the serological survey of Toxoplasma antibodies in local.horses from three major regions: a neighbourhood of a city in the North (Sidi Thabet), a neighbourhood of a city on the coast (Monastir) and a neighbourhood of a city in the middle (Battan) of Tunisia (North of Africa). Methods: A total of 158 serum samples were obtained from clinically healthy horses which consisted of 111 (32 female, 79 male) 2-10 years old and 47 (11 female, 36 male) older than 10 years. All of the horses were tested for antibodies to T. gondii using the Modified Agglutin...
Fatal infection in two Icelandic stallions caused by Halicephalobus gingivalis (Nematoda: Rhabditida). Opportunistic infections with the free living nematode Halicephalobus gingivalis are infrequently reported in horses but the cases are widespread geographically. The nematodes are believed to penetrate wounds and subsequently reproduce within the host tissues. This paper reports two cases of a fatal disease in stallions of the Icelandic breed in Iceland. Case 1: a stallion, which sustained injuries to the mouth after an accident, developed severe neurological signs and had to be euthanatized. Histological examination revealed mild inflammation and malacia in the cerebellum associated with the ...
Cloning of equine herpesvirus type 1 438/77 strain genome as a bacterial artificial chromosome. Equine herpesvirus type 1 (EHV-1) is a major cause of respiratory and reproductive diseases in horses worldwide. The genome of EHV-1 strain 438/77 (isolated from an aborted equine fetus) was cloned as a bacterial artificial chromosome (BAC) in E. coli without any gene deletions. The mini-F plasmid sequence was inserted in the middle of ORF19 and 20 via homologous recombination following co-transfection of viral DNA and plasmid pE19_20/HA into RK13 cells. Circular viral DNA was extracted from RK13 cells infected with purified recombinant virus expressing green fluorescent protein (GFP) and elec...
A prospective longitudinal study of naturally infected horses to evaluate the performance characteristics of rapid diagnostic tests for equine influenza virus. An outbreak of equine influenza (EI) occurred in Australia in 2007. During the laboratory support for this outbreak, real-time reverse transcriptase polymerase chain reaction (qRT-PCR) assays and a blocking enzyme linked immunosorbent assay (bELISA) were used as testing methods to detect infection with the virus. The qRT-PCR and bELISA tests had not been used for EI diagnosis before, so it was not known how soon after infection these tests would yield positive results, or for how long these results would remain positive. To answer these questions, nasal swabs and blood samples were collected d...
In vitro activity of ponazuril against Theileria equi. The equid hemoprotozoan parasite Theileria equi is endemic in most regions worldwide. Infection of horses is a cause of significant economic loss due to costs associated with disease and restriction of trade with non-endemic nations. The ability of certain drugs such as imidocarb dipropionate to eliminate persistent T. equi infection and transmission risk is controversial. The anti-protozoal agent ponazuril has been used successfully to treat equine Sarcosystis neurona and Toxoplasma gondii. The hypothesis that ponazuril inhibits replication of T. equi in vitro was tested. T. equi infected equ...
Submandibular lymph node abscess caused by Actinomyces denticolens in a horse in Ontario. This is the first report of the isolation of Actinomyces denticolens, an opportunistic pathogen, from a draining submandibular lymph node abscess in a horse in Ontario. Due to the similarity of the clinical signs with strangles, this pathogen should be included in the differential diagnosis of submandibular lymphadenopathy in the horse. Il s’agit du premier rapport d’isolement d’ un agent pathogène opportuniste, lors du drainage d’un abcès d’un ganglion lymphatique sous-maxillaire chez un cheval en Ontario. En raison de la similarité des signes cliniques avec ceux de la gourme, ...
Granulocytic anaplasmosis in a horse from Nova Scotia caused by infection with Anaplasma phagocytophilum. A 16-year-old Paint stallion was presented with intermittent fever, inappetance, lethargy, icterus, distal limb edema, and submandibular lymphadenopathy. The horse was native to Nova Scotia and had never left that province. Morulae were detected in granulocytes. Ananaplasma phagocytophilum infection was confirmed by serology and polymerase chain reaction (PCR). The horse responded to treatment with oxytetracycline. Anaplasmose granulocytaire chez un cheval de la Nouvelle-Écosse causée par une infection par Anaplasma phagocytophilum. Un étalon Paint âgé de 16 ans a été présenté avec un...
Diagnosis, treatment, control, and prevention of infections caused by Rhodococcus equi in foals. Rhodococcus equi, a gram-positive facultative intracellular pathogen, is one of the most common causes of pneumonia in foals. Although R. equi can be cultured from the environment of virtually all horse farms, the clinical disease in foals is endemic at some farms, sporadic at others, and unrecognized at many. On farms where the disease is endemic, costs associated with morbidity and mortality attributable to R. equi may be very high. The purpose of this consensus statement is to provide recommendations regarding the diagnosis, treatment, control, and prevention of infections caused by R. equi...
Development and application of loop-mediated isothermal amplification methods targeting the seM gene for detection of Streptococcus equi subsp. equi. Loop-mediated isothermal amplification (LAMP) constitutes a potentially valuable diagnostic tool for rapid diagnosis of contagious diseases. In this study, we developed a novel LAMP method (seM-LAMP) to detect the seM gene of Streptococcus equi subsp. equi (S. equi), the causative agent of strangles in equids. The seM-LAMP successfully amplified the target sequence of the seM gene at 63°C within 60 min. The sensitivity of the seM-LAMP was slightly lower than the 2nd reaction of the seM semi-nested PCR. To evaluate the species specificity of the seM-LAMP, we tested 100 S. equi and 189 non-S. e...
Relationship of biosecuriy practices with the use of antibiotics for the treatment of infectious disease on U.S. equine operations. This study is the first report estimating, on a national basis, the use of various biosecurity practices, singly and in combination, on U.S. equine operations. Use of biosecurity practices is described for operations by risk level, based on reported exposure of resident horses to outside horses during the previous 12 months. In addition, the association between use of various biosecurity practices and use of antibiotics to treat infectious disease in both adult equids and foals is reported. The comparison of these study findings with previously reported data in the literature is limited by the...
Rhodococcus equi pneumonia in the foal–part 2: diagnostics, treatment and disease management. Various challenges face clinicians and farm managers in diagnosing, treating and preventing Rhodococcus equi pneumonia. The use of ultrasound imaging has aided in the early diagnosis of the disease, reducing treatment duration and improving therapeutic outcomes. Antimicrobial resistance in R. equi is an emerging issue that necessitates prudent antimicrobial therapy of diseased foals. Alternative methods of disease transmission, such as contagious foal-to-foal aerosol transmission, may need to be addressed to complement dust reduction environmental strategies and to minimise the overall risk of...
Functional characterization of EUL47 in productive replication, morphogenesis and infectivity of equine herpesvirus 1. EUL47 is a major component of the tegument of equine herpesvirus 1 (EHV-1). To determine its function, we used Red/ET cloning to delete its gene (gene 13) from EHV-1 strain Ab4p inserted into a bacterial artificial chromosome (BAC), yielding Ab4pattBΔ13. We also examined the reverted virus (Ab4pattB13R). Ab4pattBΔ13 replicated in rabbit kidney (RK)-13 cells, indicating that ORF13 is dispensable for virus replication in cell culture. Its intracellular and extracellular titers were about 10- and 100-fold lower than those of the revertant and parent strains, respectively. In addition, the plaqu...
Evaluation of the usefulness of a PCR assay performed at a clinical laboratory for the diagnosis of respiratory disease induced by equine herpesvirus type 1 in the field. A PCR assay for the diagnosis of respiratory disease induced by equine herpesvirus type 1 (EHV-1) was performed at the clinical laboratory in the Racehorse Clinic of the Ritto Training Center of the Japan Racing Association from December 2007 to March 2008. The assay was performed without the trouble of contamination throughout the study and its turnaround time was approximately 6 hr. The PCR detection rates of EHV-1 among seroconverted horses were 22.2% for nasal swabs and 33.3% for blood samples. However, EHV-1 DNA was also detected in horses without seroconversion at a low rate. These resul...
Bartonellae in animals and vectors in New Caledonia. Bartonellae are gram-negative facultative intracellular alpha-proteobacteria from the family Bartonellaceae. The natural history of bartonellae consists of a reservoir/host, which is a vertebrate with chronic intravascular infection with sustained bacteremia, and a vector (usually an arthropod) that transfers the bacteria from the reservoir to a susceptible yet uninfected host. In order to reveal the sources and reservoirs of Bartonella infection in animals and vectors in New Caledonia, we collected the blood samples of 64 dogs, 8 cats, 30 bovines, 25 horses and 29 wild deer Cervus timorensis ...
Mucosal co-immunization of mice with recombinant lactococci secreting VapA antigen and leptin elicits a protective immune response against Rhodococcus equi infection. Rhodococcus equi causes severe pneumonia in foals and has recently gained attention as a significant opportunistic pathogen in immunocompromised humans. However, no effective vaccine to prevent rhodococcosis is currently available. In this study, we have engineered the food-grade bacterium Lactococcus lactis to secrete the virulence-associated protein A from R. equi (LL-VapA). The immunogenic potential of LL-VapA strain was then evaluated after either intragastric or intranasal immunization in mice either alone or in combination with LL-Lep, a recombinant strain of L. lactis secreting biologic...
Outbreak of equine endometritis caused by a genotypically identical strain of Pseudomonas aeruginosa. Pseudomonas aeruginosa is an opportunistic pathogen that has been recognized as a cause of endometritis in mares. Pulsed field gel electrophoresis was used to characterize and compare isolates of P. aeruginosa from an outbreak of endometritis and unrelated isolates collected at the same time as the outbreak. The restriction endonuclease digestion patterns and antimicrobial resistance profiles of all outbreak isolates were identical. Therefore, a single strain of P. aeruginosa was responsible for the cases of endometritis. The unrelated isolates could be distinguished from the outbreak strain u...
Rhodococcus equi pneumonia in the foal–part 1: pathogenesis and epidemiology. Rhodococcus equi pneumonia is a worldwide infectious disease of major concern to the equine breeding industry. The disease typically manifests in foals as pyogranulomatous bronchopneumonia, resulting in significant morbidity and mortality. Inhalation of aerosolised virulent R. equi from the environment and intracellular replication within alveolar macrophages are essential components of the pathogenesis of R. equi pneumonia in the foal. Recently documented evidence of airborne transmission between foals indicates the potential for an alternative contagious route of disease transmission. In the...
