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.
Bustos CP, Leiva CL, Gambarotta M, Guida N, Chacana PA.Equine salmonellosis is caused by several Salmonella serotypes, including Salmonella Newport, which cause enterocolitis and diarrhea. Treatment usually includes the administration of antibiotics. However, since multidrug-resistant Salmonella is commonly detected, alternative options to control the pathogen are needed. One of these options is the use of specific egg yolk antibodies (IgY) for passive immunotherapy. Thus, the aim of our work was to produce IgY antibodies against an equine S. Newport strain and assess their in vitro inhibitory activity. To this end, laying hens were immunized with...
Olguin-Perglione C, Barrandeguy ME.Equine influenza virus (EIV) is one of the most important respiratory pathogens of horses as outbreaks of the disease lead to significant economic losses worldwide. In this review, we summarize the information available on equine influenza (EI) in South America. In the region, the major events of EI occurred almost in the same period in the different countries, and the EIV isolated showed high genetic identity at the hemagglutinin gene level. It is highly likely that the continuous movement of horses, some of them subclinically infected, among South American countries, facilitated the spread o...
Hu D, Chao Y, Zhang B, Wang C, Qi Y, Ente M, Zhang D, Li K, Mok KM.Horse botflies have been a threat to the Przewalski's horses in the Kalamaili Nature Reserve in Xinjiang of China since their reintroduction to the original range. As larvae of these parasites could infest the intestine of a horse for months, they could interact with and alter the structure and composition of its intestinal microbiota, affecting adversely its health. Nonetheless, there are no such studies on the rewilded Przewalski's horses yet. For the first time, this study characterizes the composition of the intestinal microbiota of 7 rewilded Przewalski's horses infected severely by Gaste...
León G, Herrera M, Vargas M, Arguedas M, Sánchez A, Segura Á, Gómez A, Solano G, Corrales-Aguilar E, Risner K, Narayanan A, Bailey C, Villalta M....In the current global emergency due to SARS-CoV-2 outbreak, passive immunotherapy emerges as a promising treatment for COVID-19. Among animal-derived products, equine formulations are still the cornerstone therapy for treating envenomations due to animal bites and stings. Therefore, drawing upon decades of experience in manufacturing snake antivenom, we developed and preclinically evaluated two anti-SARS-CoV-2 polyclonal equine formulations as potential alternative therapy for COVID-19. We immunized two groups of horses with either S1 (anti-S1) or a mixture of S1, N, and SEM mosaic (anti-Mix) ...
Williams ZJ, Sage A, Valberg SJ.The coronavirus pandemic abruptly halted all in-person clerkships, or clinical rotations, for clinical veterinary students across the United States. Online clerkships in radiology offered the opportunity to expand the student's ability to interpret medical images but did not allow for the development of physical hands-on imaging skills recognized as core competencies in veterinary medicine. The present report highlights the value of providing veterinary students with a smartphone-associated Butterfly iQ point-of-care ultrasound during a 3-week self-driven virtual clerkship. During the virtual ...
Kambayashi Y, Bannai H, Tsujimura K, Hirama A, Ohta M, Nemoto M.In 2020, an outbreak of equine coronavirus (ECoV) infection occurred among 41 horses at a riding stable in Tokyo, Japan. This stable had 16 Thoroughbreds and 25 horses of other breeds, including Andalusians, ponies and miniature horses. Fifteen horses (37 %) showed mild clinical signs such as fever, lethargy, anorexia and diarrhoea, and they recovered within 3 days of onset. A virus neutralization test showed that all 41 horses were infected with ECoV, signifying that 26 horses (63 %) were subclinical. The results suggest that subclinical horses played an important role as spreaders. A genome ...
Scala A, Tamponi C, Sanna G, Predieri G, Meloni L, Knoll S, Sedda G, Dessì G, Cappai MG, Varcasia A.Equine ascariosis, caused by Parascaris spp., is a worldwide endoparasitic disease affecting young horses in particular. Despite the great number of horses reared in Italy, large-scale epidemiological surveys dealing with ascariosis prevalence in the country are not reported in the current literature. For this reason, the present survey aims to describe, for the first time, the spread and infestation of Parascaris spp. in a large population of Italian horses (6896 animals) using faecal egg counts, and further to identify risk factors associated with ascarid egg shedding. Methods: Individual re...
Uiterwijk M, Ibáñez-Justicia A, van de Vossenberg B, Jacobs F, Overgaauw P, Nijsse R, Dabekaussen C, Stroo A, Sprong H.Ticks of the genus Hyalomma, which are vectors for several tick-borne diseases, are occasionally found in areas outside their endemic range including northern parts of Europe. The objective of this study was to analyse adult Hyalomma ticks that were recently found in the Netherlands. Methods: Hyalomma ticks were morphologically identified. Cluster analysis, based upon sequence data (cox1 barcoding) for molecular identification, and pathogen detection were performed. Additionally, a cross-sectional survey of horses was conducted to actively search for Hyalomma ticks in summer 2019. Analysis of...
Outammassine A, Zouhair S, Loqman S.Rift Valley Fever (RVF) and West Nile virus (WNV) are two important emerging Arboviruses transmitted by Aedes and Culex mosquitoes, typically Ae. caspius, Ae. detritus and Cx. pipiens in temperate regions. In Morocco, several outbreaks of WNV (1996, 2003 and 2010), affecting horses mostly, have been reported in north-western regions resulting in the death of 55 horses and one person cumulatively. Serological evidence of WNV local circulation, performed one year after the latest outbreak, revealed WNV neutralizing bodies in 59 out of 499 tested participants (El Rhaffouli et al., 2012). The coun...
Payette F, Charlebois A, Fairbrother JH, Beauchamp G, Leclere M.Nicoletella semolina was identified in the airways of horses and its low prevalence could be because of its difficult differentiation from other Pasteurellaceae. Objective: To develop a molecular method for the identification of N. semolina and to evaluate its prevalence in the mouth and the airways of healthy and severe asthmatic horses. Methods: Six healthy and 6 severely asthmatic horses in phase I, 10 severely asthmatic horses in phase II, and 10 healthy horses in phase III. Methods: Cohort (phases I and II) and cross-sectional (phase III) studies. Quantitative polymerase chain reaction pr...
Sullivan E, Lecollinet S, Kerviel A, Hue E, Pronost S, Beck C, Dumarest M, Zientara S, Roy P.African horse sickness virus (AHSV) is an Orbivirus within the Reoviridae family, spread by Culicoides species of midges, which infects equids with high mortality, particularly in horses and has a considerable impact on the equine industry. In order to control the disease, we previously described Entry Competent Replication Abortive (ECRA) virus strains for each of the nine distinct AHSV serotypes and demonstrated their potential as vaccines, first in type I interferon receptor (IFNAR-/-) knockout mice, and then in ponies. In this report we have investigated whether or not a combination ECRA v...
Luethy D, Feldman R, Stefanovski D, Aitken MR.Acute colitis is a serious cause of morbidity and death in horses. Recent studies have compared clinical features of coronavirus and salmonellosis, but no study has compared clinical features of enteric salmonellosis, coronavirus, and neorickettsiosis. Objective: To identify risk factors for laminitis and nonsurvival to discharge in horses with enteric salmonellosis, coronavirus, or neorickettsiosis. Methods: Eighty-five horses hospitalized for acute colitis from 2011 to 2019. Methods: Retrospective case series. Medical record review (2011-2019) of adult (≥2 years) horses with colitis. Pri...
Seeger MG, Corrêa LFD, Clothier KA, Loy JD, Cargnelutti JF.Infectious keratoconjunctivitis (IKC) is the most frequent ocular disease in livestock worldwide and is primarily caused by Moraxella bovis, M. ovis, and/or M. bovoculi. The economic impact of IKC is mainly due to ocular damage, which leads to weight loss, management difficulties, pain and discomfort, and cost of treatments. In horses, limited information is available on the association of Moraxella spp. with keratoconjunctivitis. The present report describes two cases of equine keratoconjunctivitis caused by members of the genus Moraxella. Both animals presented with lacrimation, conjunctivit...
Watanabe R, Furuta H, Ueno Y, Nukada T, Niwa H, Shinyashiki N, Kano R.Trichophyton bullosum is a zoophilic dermatophyte that has been rarely isolated from horses and humans in Africa and Europe. This is the first reported isolation of T. bullosum from a horse with dermatophytosis in Japan. The isolate from a skin lesion formed a cream-colored and waxy colony that was slightly elevated in the center. Sequencing of the internal transcribe spacer region of the isolate revealed that it was 100% identical to that of T. bullosum.
Onzere CK, Fry LM, Bishop RP, Silva MG, Bastos RG, Knowles DP, Suarez CE.Theileria equi is a widely distributed apicomplexan parasite that causes severe hemolytic anemia in equid species. There is currently no effective vaccine for control of the parasite and understanding the mechanism that T. equi utilizes to invade host cells may be crucial for vaccine development. Unlike most apicomplexan species studied to date, the role of micronemes in T. equi invasion of host cells is unknown. We therefore assessed the role of the T. equi claudin-like apicomplexan microneme protein (CLAMP) in the invasion of equine erythrocytes as a first step towards understanding the role...
Abu-Seida AM, Wafy MN, Hassan EA, Ahmed KA.Ocular neoplasms represent 10% of all equine neoplasms and ocular squamous cell carcinoma (OSCC) is the most common one. This report describes the clinical presentation, laboratory, ultrasonography, postmortem, histopathology and immunohistochemistry findings of a mixed ocular neoplasm in a 10-year-old draft mare. The mare had a one-year history of left ocular mass. Complete destruction of the left eye with loss of vision was observed. A large ulcerated mass oozing blood replaced the left eye. Left parotid lymph node was swollen and had a sinus tract discharging pus. Ultrasonography revealed a...
Klouth E, Zablotski Y, Goehring LS.Equid herpesvirus type 1 (EHV-1) causes several outbreaks of abortion and/or equid herpesvirus-associated myeloencephalopathy (EHM) worldwide each year. EHM is of great concern, as permanent neurological gait anomalies can leave a horse unfit for future use. The study assesses the risk factors associated with the occurrence of EHM. During an unmitigated outbreak, 141 adult horses/ponies of several distinct breeds were evaluated-using multiple Bayesian logistic regression calculating the odds ratios for breed, age, and sex. In total, 33 of the 141 horses showed signs of EHM. Fjord horses and wa...
Ogihara K, Ishihara A, Nagai M, Yamada K, Mizutani T, Harafuji M, Nishio H, Madarame H.A 23-year-old Falabella gelding kept in Tochigi, Japan, for more than 20 years presented with a recurrent mass of the glans penis that was first noticed about a year earlier. Partial phallectomy was performed with no adjunctive therapy for local regrowth of the mass. The horse was euthanized 3 months after surgery for urinary retention due to suspected regrowth. The resected mass affected the genital and urethral mucosa of the glans penis, and was diagnosed as equine sarcoid by histopathology and identification of bovine papillomavirus (BPV) DNA. Phylogenetic analysis of the BPV genome of the ...
Onder Z, Yildirim A, Pekmezci D, Duzlu O, Pekmezci GZ, Ciloglu A, Simsek E, Kokcu ND, Yetismis G, Ercan N, Inci A.A total of 1340 fresh fecal samples from farm and pet animals in Central Anatolia and the Middle Black Sea Region of Turkey were investigated using a PCR assay targeting the SSU rRNA of Blastocystis sp. An overall Blastocystis sp. prevalence of 19.4% (183/940) was found in farm animals, including cattle, sheep, water buffaloes, and chickens. Fecal samples of dogs, cats, and horses were negative. The highest prevalence of Blastocystis sp. was found in sheep (38.2%) among the farm animals. The SSU rRNA sequence analysis revealed two animal-specific subtypes, including ST10 in cattle and sheep an...
Tuvshintulga B, Nugraha AB, Mizutani T, Liu M, Ishizaki T, Sivakumar T, Xuan X, Yokoyama N, Igarashi I.Theileria equi, an intraerythrocytic protozoan parasite, causes equine piroplasmosis, a disease which negatively impacts the global horse industry. Genetic manipulation is one of the research tools under development as a control method for protozoan parasites, but this technique needs to be established for T. equi. Herein, we report on the first development of a stable transgenic T. equi line expressing enhanced green fluorescent protein/blasticidin S deaminase (eGFP/BSD). To express the exogenous fusion gene in T. equi, regulatory regions of the elongation factor-1 alpha (ef-1α) gene were id...
Butler D, Upton L, Mullan S.In March 2020, the World Health Organisation called for countries to take urgent and aggressive action against a global pandemic caused by COVID-19. Restrictions were introduced in many countries to reduce transmission of COVID-19 and ultimately deaths. Such restrictions have been colloquially referred to as "lockdown". Anecdotal evidence of the beneficial practices that facilitated safe veterinary treatment and equine care had been reported together with an increase in the use of electronic communication and information technologies during the first "lockdown". Thus, the aim of this qualitati...
Reck C, Menin Á, Batista F, Meira Santos PO, Miletti LC.Surra is an infectious disease caused by , which affects a large number of domestic and wild animal species. Infection control is based on rapid diagnosis followed by treatment of sick animals. This study aimed to evaluate a buffered antigen and rapid serum agglutination test (BA/Te) for the detection of anti- antibodies in serum samples of horses. For this purpose, 445 serum samples from horses were evaluated and the results compared with the diagnosis by CATT/. Our data show a sensitivity of 92%, specificity of 91% and a degree of agreement kappa () of 0.82 (95% CI: 0.771-0.877, < 0...
Idoko IS, Edeh RE, Adamu AM, Machunga-Mambula S, Okubanjo OO, Balogun EO, Adamu S, Johnson W, Kappmeyer L, Mousel M, Ueti MW.Equine piroplasmosis, an economically important disease of equids caused by the hemoprotozoan parasites , , and , has a worldwide distribution. These parasites are transmitted by ixodid ticks. To improve the detection of horses in Nigeria exposed to piroplasm parasites, 72 horses with variable clinical signs of piroplasmosis were sampled from Northwest and Northcentral Nigeria and tested by nPCR and cELISA. Blood and serum samples were collected from each horse via jugular venesection. Individually, nPCR or cELISA failed to identify all horses exposed to piroplasms. A combination of species-sp...
Zhu Y, Chen S, Yi Z, Holyoak R, Wang T, Ding Z, Li J. subsp. equi () is the pathogen causing strangles, a highly infectious disease that can affect equids including donkeys of all ages. It can persistently colonize the upper respiratory tract of animals asymptomatically for years, which serves as a source of infection. Several strangles outbreaks have been reported in the donkey industry in China in the last few years and pose a great threat to health, production, and the welfare of donkeys. Nasopharyngeal swab samples for culture and PCR are used widely in strangles diagnosis. Additionally, microbiomes within and on the body are essential to ho...
Chen N, Liu Y, Qin P, Li Y, Ma D, Li J, Shi T, Zhu Z.The microorganisms in the cecum of donkeys share similar functions as those in the rumen of cattle. Transformation of the cecal microenvironment by probiotics plays an important role in the health and growth of donkeys. In order to screen out excellent donkey probiotic preparations, in this study, we isolated an antibacterial strain of Bacillus amyloliquefaciens (designated as DQB-1) from the cecum of Dezhou donkey. The strain was assessed in terms of antibacterial activity, antibacterial substance analysis, and stability. The results show that, the Bacillus amyloliquefaciens DQB-1 exhibited p...
Rhinosporidiosis is caused by Rhinosporidium seeberi, a parasitic organism of the family Rhinosporideacea family, class Micomycetozoa. The disease is endemic in India; however, some cases were reported in Europe, Africa, North America, and South America. The aim of the present study is to report three cases of rhinosporidiosis in wild horses in different cities of Buenos Aires province, Argentina. We confirm the presence of R. seeberi in the analyzed samples using histopathological and PCR sequencing techniques.
Kauter A, Epping L, Ghazisaeedi F, Lübke-Becker A, Wolf SA, Kannapin D, Stoeckle SD, Semmler T, Günther S, Gehlen H, Walther B.Previous research identified veterinary clinics as hotspots with respect to accumulation and spread of multidrug resistant extended-spectrum β-lactamase (ESBL)-producing (EC). Therefore, promoting the prudent use of antibiotics to decrease selective pressure in that particular clinical environment is preferable to enhance biosecurity for animal patients and hospital staff. Accordingly, this study comparatively investigated the impact of two distinct perioperative antibiotic prophylaxis (PAP) regimens (short-term versus prolonged) on ESBL-EC carriage of horses subjected to colic surgery. Whil...
Equine infectious anemia (EIA) is a viral disease, caused by the Equine Infectious Anemia virus (EIAV) belonging to the Retroviridae family, genus Lentivirus. Horses (or equids) infected with EIAV are lifelong carriers and they remain contagious for other horses even in the absence of clinical signs. So far, EIAV infection has been reported among horses in North and South America, France, Germany, Italy, Hungary and Romania, with no publication regarding the presence of EIAV in horses in Serbia. To determine the circulation of EIAV among, approximately, the 5000 horses of the Vojvodina region,...
Nemoto M, Ohta M, Yamanaka T, Kambayashi Y, Bannai H, Tsujimura K, Yamayoshi S, Kawaoka Y, Cullinane A.From late 2018 to 2019, equine influenza virus (EIV) strains of Florida sublineage clade 1 (Fc1), which had until then been circulating mainly in the United States, suddenly spread across Europe causing many outbreaks, and Florida sublineage clade 2 (Fc2) strains, which had been circulating mainly in Europe, have not been detected in Europe since 2018. Since 2010, the World Organisation for Animal Health (OIE) has recommended that EIV vaccines contain an Fc1 strain that is like A/equine/South Africa/4/2003 or A/equine/Ohio/2003. Accordingly, Japanese vaccines contain A/equine/Ibaraki/1/2007 as...
Attoui H, Sailleau C, Mohd Jaafar F, Belhouchet M, Biagini P, Cantaloube JF, de Micco P, Mertens P, Zientara S.The complete nucleotide sequence of Middelburg virus (MIDV) was determined for strain MIDV-857 from Zimbabwe. The isolation of this virus in 1993 from a horse that died showing severe clinical signs represents the first indication that MIDV can cause severe disease in equids. Full-length cDNA copies of the viral genome were successfully synthesized by an innovative RT-PCR amplification approach using an 'anchor primer' combined with the SMART methodology described previously for the synthesis of full-length cDNA copies from genome segments of dsRNA viruses. The MIDV-857 genome is 11,674 nt, ex...
Raeghi S, Akaberi A, Sedeghi S.Toxoplasma gondii is a zoonotic protozoan parasite found worldwide and responsible for major economic losses in most classes of livestock. This study was aimed to determine the prevalence of T. gondii infection in sheep, cattle and horses in Urmia, north-west of Iran, using MAT. Methods: Blood samples of 276 livestock and 26 horses were collected from July 2009 till April 2010. The data were analyzed by the Chi-square, Fisher's Exact and Cochran's and Mantel-Haenszel Tests. The level of significance was set at P<0.05. Results: Thirty-three (21.1%) sheep, 2 (1.6%) cattle and 3 (11.5%) horses...
Sallé G, Guillot J, Tapprest J, Foucher N, Sevin C, Laugier C.Horses are infected by a wide range of parasite species that form complex communities. Parasite control imposes significant constraints on parasite communities whose monitoring remains, however, difficult to track through time. Postmortem examination is a reliable method to quantify parasite communities. Here, we compiled 1,673 necropsy reports accumulated over 29 years, in the reference necropsy centre from Normandy (France). The burden of non-strongylid species was quantified and the presence of strongylid species was noted. Details of horse deworming history and the cause of death were reg...
Grooters AM, Whittington A, Lopez MK, Boroughs MN, Roy AF.The purpose of this study was to evaluate the effects of sample handling, storage, and culture techniques on the isolation of Pythium insidiosum from infected equine tissues. Tissue and kunker samples obtained immediately posteuthanasia from a horse with subcutaneous pythiosis were used to assess the effects of sample type (kunkers vs. tissues), media type (selective vs. nonselective), storage technique, and storage time on P. insidiosum isolation rate. Overall, isolation rates were higher from fresh kunkers (94.6%) and stored kunkers (76.4%) than from fresh tissues (8.3%) or stored tissues (4...
Nieri-Bastos FA, Lopes MG, Cançado PH, Rossa GA, Faccini JL, Gennari SM, Labruna MB.Adult ticks of the species Amblyomma parvum were collected from the vegetation in the Pantanal biome (state of Mato Grosso do Sul) and from horses in the Cerrado biome (state of Piauí) in Brazil. The ticks were individually tested for rickettsial infection via polymerase chain reaction (PCR) targeting three rickettsial genes, gltA, ompA and ompB. Overall, 63.5% (40/63) and 66.7% (2/3) of A. parvum ticks from Pantanal and Cerrado, respectively, contained rickettsial DNA, which were all confirmed by DNA sequencing to be 100% identical to the corresponding fragments of the gltA, ompA and ompB ge...
Matsuu A, Hobo S, Ando K, Sanekata T, Sato F, Endo Y, Amaya T, Osaki T, Horie M, Masatani T, Ozawa M, Tsukiyama-Kohara K.Non-primate hepacivirus (NPHV) is a recently discovered homolog of the hepatitis C virus in horses. The frequency and distribution of NPHV infections among horses in Japan is unknown. In this study, serum samples from 453 horses across Japan were screened for NPHV RNA using real-time RT-PCR and anti-nonstructural 3 protein (NS3) antibodies using the Gaussia luciferase immunoprecipitation system assay. In order to monitor the course of NPHV infection in horses, we examined 31 stored samples (9 adult horses and 22 young horses) obtained one year ago and compared the results to the recent data. S...
Cauchard S, Bermúdez-Humarán LG, Blugeon S, Laugier C, Langella P, Cauchard J.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...
Naureen A, Saqib M, Muhammad G, Hussain MH, Asi MN.The Rose Bengal plate agglutination test (RBT) was evaluated for the diagnosis of equine glanders, and its diagnostic efficiency was compared with that of mallein and other serological tests, including indirect hemagglutination test (IHAT), complement fixation test (CFT), and modified counter immunoelectrophoresis test (mCIET). Sera from 70 naturally infected culture-positive, 96 potentially exposed cohorts, and 110 healthy equines were tested. All tests but mCIET showed 100% specificity when testing the sera from glanders-negative equines. The calculated sensitivities of RBT, IHAT, CFT, mCIET...
Nadler SA, Carreno RA, Adams BJ, Kinde H, Baldwin JG, Mundo-Ocampo M.Phylogenetic relationships among six isolates of Halicephalobus gingivalis (Stefanski, 1954), a species with pathogenic potential in horses and humans, were evaluated using DNA sequences from the nuclear large-subunit ribosomal RNA (LSU rDNA) gene. Sequences from nematodes obtained from in vitro cultures (soil or clinical sources), or isolated from infected horse tissues, were compared. Gene sequences from a fatal equine clinical case from southern California and a free-living isolate recovered from southern California soil showed no fixed differences. Sequences from isolates representing two ...
Pusterla N, Huder JB, Feige K, Lutz H.This case report describes a 12-year-old Arabian mare with granulocytic ehrlichiosis. Clinical signs included fever, apathy, anorexia, icterus, limb edema, and reluctance to move. Examination of buffy coat smears revealed Ehrlichia organisms in neutrophils and eosinophils. A band of 1,428 bp was amplified from DNA of leukocytes via nested PCR and was identified as part of the Ehrlichia 16S rRNA gene. It differed from the gene sequences of Ehrlichia phagocytophila and E. equi at two and three positions, respectively. Interestingly, the nucleotide sequence of the 16S rRNA was 100% identical to t...
Rodriguez L, Reedy S, Nogales A, Murcia PR, Chambers TM, Martinez-Sobrido L.H3N8 equine influenza virus (EIV) is an important and significant respiratory pathogen of horses. EIV is enzootic in Europe and North America, mainly due to the suboptimal efficacy of current vaccines. We describe, for the first time, the generation of a temperature sensitive (ts) H3N8 EIV live-attenuated influenza vaccine (LAIV) using reverse-genetics approaches. Our EIV LAIV was attenuated (att) in vivo and able to induce, upon a single intranasal administration, protection against H3N8 EIV wild-type (WT) challenge in both a mouse model and the natural host, the horse. Notably, since our EIV...
Ciarlet M, Reggeti F, Piña CI, Liprandi F.Two group A rotavirus strains isolated from diarrheic foals in Venezuela were classified as belonging to G14 serotype by cross-neutralization tests and on the basis of the homology of the sequenced VP7 gene. This report confirms that rotavirus strains of G14 serotype specificity circulate among equine populations.
Wernery U, Wernery R, Joseph M, Al-Salloom F, Johnson B, Kinne J, Jose S, Jose S, Tappendorf B, Hornstra H, Scholz HC.We confirm a natural infection of dromedaries with glanders. Multilocus variable number tandem repeat analysis of a Burkholderia mallei strain isolated from a diseased dromedary in Bahrain revealed close genetic proximity to strain Dubai 7, which caused an outbreak of glanders in horses in the United Arab Emirates in 2004.
Okely M, Anan R, Gad-Allah S, Samy AM.Ticks are important vectors of emerging health problems in humans and animals. We conducted several field surveillances to investigate the fauna of hard ticks on domestic animals in seven governorates of Egypt during 2018-2019. A total of 3265 individual tick specimens were collected and identified to the species level; the specimens belong to 11 species within three genera (Amblyomma, Hyalomma, and Rhipicephalus). Tick infestation was highest in dromedary camels (70%), followed by dogs (52.5%), cattle (50%), buffaloes (38%), and horses (12%). Ten species were collected from dromedary camels, ...
Hooper-McGrevy KE, Wilkie BN, Prescott JF.The purpose of this study was to determine whether foals immunized orally from 2 days of age with virulent Rhodococcus equi developed a protective pulmonary immune response and to characterise the antibody response of the immunized foals to the virulence-associated proteins (Vaps) of the bacterium. Two groups of foals were used. One (n=4) was given live R. equi ATCC 33701 orally at 2, 7, and 14 days of age. The second group comprised three non-immunized foals age-matched to the vaccinates. At 3 weeks of age, 1 week after the final immunization, both groups were challenged intrabronchially with...
We found a male Hyalomma rufipes Koch, 1844 tick feeding on a horse grazing near Valtice, south Moravia, Czech Republic on October 24, 2019. The horse was born in Czechland and did not leave the country at least during the last five years. Relevant findings of Hyalomma ticks in other parts of central Europe are reviewed, including also records of pre-imaginal Hyalomma marginatum complex ticks on migrating birds all over Europe.
Anastasi E, Giguère S, Berghaus LJ, Hondalus MK, Willingham-Lane JM, MacArthur I, Cohen ND, Roberts MC, Vazquez-Boland JA.The objective of this study was to identify the molecular mechanism of macrolide resistance in the actinomycete Rhodococcus equi, a major equine pathogen and zoonotic agent causing opportunistic infections in people. Methods: Macrolide-resistant (n = 62) and macrolide-susceptible (n = 62) clinical isolates of R. equi from foals in the USA were studied. WGS of 18 macrolide-resistant and 6 macrolide-susceptible R. equi was performed. Representative sequences of all known macrolide resistance genes identified to date were used to search the genome assemblies for putative homologues. PCR w...
Abutarbush SM, Alqawasmeh DM, Mukbel RM, Al-Majali AM.The purposes of this study were to estimate the seroprevalence and distribution of horse piroplasmosis, to evaluate risk factors associated with the occurrence of the disease and to compare the different diagnostic methods used for this disease. A total of 253 clinically normal horses were sampled, and a collection form was completed for each horse from five of six different climatic zones of Jordan. The sixth zone was not sampled because it did not include horse population. Competitive enzyme-linked immunosorbent assay (cELISA) revealed 37 horses (14.6%) positive for Theileria equi, and none ...
Molenkamp R, Rozier BC, Greve S, Spaan WJ, Snijder EJ.Equine arteritis virus (EAV), the type member of the family Arteriviridae, is a single-stranded RNA virus with a positive-stranded genome of approximately 13 kb. EAV uses a discontinuous transcription mechanism to produce a nested set of six subgenomic mRNAs from which its structural genes are expressed. We have generated the first documented arterivirus defective interfering (DI) RNAs by serial undiluted passaging of a wild-type EAV stock in BHK-21 cells. A cDNA copy of the smallest DI RNA (5.6 kb) was cloned. Upon transfection into EAV-infected BHK-21 cells, transcripts derived from this clo...
Paillot R, Robinson C, Steward K, Wright N, Jourdan T, Butcher N, Heather Z, Waller AS.Streptococcus equi is the causative agent of strangles, the most frequently diagnosed infectious disease of horses worldwide. The disease is characterized by abscessation and swelling of the lymph nodes of the head and neck, which can literally strangle the horse to death. S. equi produces four recently acquired phage-associated bacterial superantigens (sAgs; SeeH, SeeI, SeeL, and SeeM) that share homology with the mitogenic toxins of Streptococcus pyogenes. The aim of this study was to characterize the contribution of each of these S. equi sAgs to mitogenic activity in vitro and quantify the ...
Salim BO, Hassan SM, Bakheit MA, Alhassan A, Igarashi I, Karanis P, Abdelrahman MB.The purpose of this study was to estimate the prevalence of equine piroplasmosis in Sudan. The presence of antibodies against Babesia caballi and Theileria equi was determined in serum samples obtained from 158 horses raised in different locations in Sudan by enzyme-linked immunosorbent assay (ELISA). The B. caballi 48-kDa and the T. equi EMA-2 purified recombinant proteins were used as antigens in the ELISA test. Results showed that seven (4.4%) were positive for B. caballi and 80 (63.5%) were positive for T. equi. Polymerase chain reaction (PCR) assays have been applied using primers targeti...
León G, Herrera M, Vargas M, Arguedas M, Sánchez A, Segura Á, Gómez A, Solano G, Corrales-Aguilar E, Risner K, Narayanan A, Bailey C, Villalta M....In the current global emergency due to SARS-CoV-2 outbreak, passive immunotherapy emerges as a promising treatment for COVID-19. Among animal-derived products, equine formulations are still the cornerstone therapy for treating envenomations due to animal bites and stings. Therefore, drawing upon decades of experience in manufacturing snake antivenom, we developed and preclinically evaluated two anti-SARS-CoV-2 polyclonal equine formulations as potential alternative therapy for COVID-19. We immunized two groups of horses with either S1 (anti-S1) or a mixture of S1, N, and SEM mosaic (anti-Mix) ...
Sant C, d'Abadie R, Pargass I, Basu AK, Asgarali Z, Charles RA, Georges KC.Equine piroplasmosis caused by Theileria equi and Babesia caballi is endemic in Trinidad and Tobago. Transmission occurs by ticks of the family Ixodidae. T. equi can also be transmitted transplacentally; however transplacental transmission of B. caballi is unknown. This study aims to investigate transplacental transmission of equine piroplasmosis from thoroughbred mares naturally infected via the tick vector. Whole blood and serum samples were collected from 117 mares in the fifth month of pregnancy. Blood samples were also collected from each of their foals (89 in total) within the first 36h ...
Uzal FA, Arroyo LG, Navarro MA, Gomez DE, Asín J, Henderson E.Enteritis, colitis, and enterocolitis are considered some of the most common causes of disease and death in horses. Determining the etiology of these conditions is challenging, among other reasons because different causes produce similar clinical signs and lesions, and also because some agents of colitis can be present in the intestine of normal animals. We review here the main bacterial and viral causes of enterocolitis of horses, including Salmonella spp., Clostridium perfringens type A NetF-positive, C. perfringens type C, Clostridioides difficile, Clostridium piliforme, Paeniclostridium so...
Nielsen MK.Clinically important equine parasites are ubiquitous in managed horse populations. The traditional approach to parasite control is frequent administration of anthelmintics to all horses on a farm. However, increasing levels of anthelmintic resistance is forcing horse owners and veterinarians to shift this control paradigm. Treatment regimens involving routine deworming of all horses throughout the year are now being replaced by more sustainable approaches, which take in to account the importance of maintaining adequate parasite refugia. The selective therapy principle has been recommended for ...