Disease transmission in horses refers to the spread of infectious agents such as bacteria, viruses, fungi, and parasites among equine populations. These pathogens can be transmitted through various routes, including direct contact, vector-borne transmission, or environmental exposure. Factors influencing disease transmission include horse density, management practices, and biosecurity measures. Understanding the mechanisms and conditions that facilitate the spread of diseases is essential for developing effective prevention and control strategies. This page compiles peer-reviewed research studies and scholarly articles that investigate the modes of transmission, risk factors, and management practices related to infectious diseases in horses.
Lotstra RJ, van den Broek J, Power T, Marr CM, Wijnberg ID.Atrial fibrillation is a common equine arrhythmia. Quinidine alone, or with digoxin are common treatments. Studies on outcome in Warmblood populations in which duration of the AF is often unknown are limited. Objective: To identify the factors that are associated with the success of full treatment cardioversion with oral medication, and establish whether there are differences in these factors between institutions. Methods: Retrospective case series using patient records of Equine University Clinic of Utrecht University and Rossdales Equine Hospital, Newmarket. Methods: Forty-nine horses treate...
Bochnia M, Ziegler J, Sander J, Uhlig A, Schaefer S, Vollstedt S, Glatter M, Abel S, Recknagel S, Schusser GF, Wensch-Dorendorf M, Zeyner A.Hypoglycin A (HGA) in seeds of Acer spp. is suspected to cause seasonal pasture myopathy in North America and equine atypical myopathy (AM) in Europe, fatal diseases in horses on pasture. In previous studies, this suspicion was substantiated by the correlation of seed HGA content with the concentrations of toxic metabolites in urine and serum (MCPA-conjugates) of affected horses. However, seed sampling was conducted after rather than during an outbreak of the disease. The aim of this study was to further confirm the causality between HGA occurrence and disease outbreak by seed sampling during ...
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...
Molaei G, Armstrong PM, Abadam CF, Akaratovic KI, Kiser JP, Andreadis TG.Eastern equine encephalitis virus (EEEV) causes a highly pathogenic mosquito-borne zoonosis that is responsible for sporadic outbreaks of severe illness in humans and equines in the eastern USA. Culiseta (Cs.) melanura is the primary vector of EEEV in most geographic regions but its feeding patterns on specific avian and mammalian hosts are largely unknown in the mid-Atlantic region. The objectives of our study were to: 1) identify avian hosts of Cs. melanura and evaluate their potential role in enzootic amplification of EEEV, 2) assess spatial and temporal patterns of virus activity during a ...
Wang JL, Zhou DH, Chen J, Liu GX, Pu WB, Liu TY, Qin SY, Yin MY, Zhu XQ.Toxoplasmosis is a worldwide zoonosis caused by Toxoplasma gondii, which can infect warm-blooded animals and humans. The present study was performed to investigate the seroprevalence of T. gondii in horses in Xinjiang, northwestern China. A total of 637 blood samples were collected from seven regions in Changji Hui Autonomous Prefecture, Xinjiang in 2011 and assayed for T. gondiiantibodies using the modified agglutination test (MAT). Risk factors (age, gender, and region) related to seroprevalence were determined by a multivariate logistic regression analysis. A total of 200 horses (31.4%, 95%...
Ravel S, Mediannikov O, Bossard G, Desquesnes M, Cuny G, Davoust B.In Senegal, several areas provide great potential for agriculture and animal production, but African animal trypanosomosis (AAT) is one of the major constraints to the development of more effective livestock production systems. A study was conducted to assess the current situation of AAT in this country. Surveys were carried out between June 2011 and September 2012 in four different areas: Dakar, Sine Saloum, Kedougou region and Basse Casamance in several animal species: dogs (152), donkeys (23), horses (63), sheep (43), goats (52) and cattle (104), distributed in the four sites. Molecular too...
Black P, Douglas I, Field H.Hendra virus was first described in 1994 in Australia, causally associated with a cluster of fatal equine and human cases at a thoroughbred racing stable in the Brisbane suburb of Hendra. This year marks the twentieth anniversary of the identification of pteropid bats (flying-foxes) as the natural host of the virus, and it is timely to reflect on a pivotal meeting of an eclectic group of scientists in that process. They included animal and public health experts, environmental scientists, veterinary and horse industry representatives, and wildlife experts. The task was to review and prioritise ...
Bhagwan J, Kumar A, Kumar R, Goyal L, Goel P, Kumar S.A sizeable Indian equine population is considered to be pre-immune carrier of Theileria equi infection. In this study we confirmed the presence of T. equi specific DNA in Hyalomma anatolicum ticks which were infested on sero-positive horses. Fifty two Indigenous horses were randomly selected from endemic areas and their blood and tick samples were collected. Tick salivary glands and blood samples were processed for separation of DNA and serum, respectively. Serum samples were analyzed by EMA-2ELISA and nine horses were found positive for T. equi specific antibodies. Species-specific primers we...
Arent Z, Gilmore C, Brem S, Ellis WA.Strains of Leptospira interrogans belonging to two very closely related serovars – Bratislava and Muenchen – are known to cause widespread infection of the horse population in many parts of the world. Conventional serological typing of isolates has been unable to differentiate between wildlife, pig, dog and possibly horse maintained isolates and therefore has been unable to provide further insight into their diversity and the relationship between them. Twenty-one such European isolates of serovar Bratislava and Muenchen were examined by restriction endonuclease analysis and multiple-locus ...
Diarra M, Fall M, Lancelot R, Diop A, Fall AG, Dicko A, Seck MT, Garros C, Allène X, Rakotoarivony I, Bakhoum MT, Bouyer J, Guis H.In Senegal, considerable mortality in the equine population and hence major economic losses were caused by the African horse sickness (AHS) epizootic in 2007. Culicoides oxystoma and Culicoides imicola, known or suspected of being vectors of bluetongue and AHS viruses are two predominant species in the vicinity of horses and are present all year-round in Niayes area, Senegal. The aim of this study was to better understand the environmental and climatic drivers of the dynamics of these two species. Culicoides collections were obtained using OVI (Onderstepoort Veterinary Institute) light traps a...
Samir A, Soliman R, El-Hariri M, Abdel-Moein K, Hatem ME.Leptospirosis is a re-emerging zoonotic disease of humans and animals worldwide. The disease is caused by pathogenic species of the genus Leptospira. These organisms are maintained in nature via chronic renal infection of carrier animals, which excrete the organisms in their urine. Humans become infected through direct or indirect exposure to infected animals and their urine or through contact with contaminated water and soil. This study was conducted to investigate Leptospira infections as a re-emerging zoonosis that has been neglected in Egypt. Methods: Samples from 1,250 animals (270 rats, ...
Acke E, Midwinter AC, Lawrence K, Gordon SJ, Moore S, Rasiah I, Steward K, French N, Waller A.To estimate the prevalence of β-haemolytic Lancefield group C streptococci in healthy dogs, cats and horses; to determine if frequent contact with horses was associated with isolation of these species from dogs and cats; and to characterise recovered S. equi subsp. zooepidemicus isolates by multilocus sequence typing. Methods: Oropharyngeal swabs were collected from 197 dogs and 72 cats, and nasopharyngeal swabs from 93 horses. Sampling was carried out at the Massey University Veterinary Teaching Hospital, on sheep and beef farms or on premises where horses were present. All animals were heal...
Finney S, Collins JA, Duggan V.The number of abandoned or otherwise neglected donkeys has significantly increased in Ireland in the recent past. The real or perceived capacity of the donkey to act as a reservoir of equine infectious disease, and thus pose an increased risk of disease transmission to horses and ponies, may be a factor in this increased abandonment and neglect. The authors here report on a field study exploring the infectious disease transmission threat the donkey poses to the general equine industry in Ireland through an examination of biosecurity standards and the views of horse and donkey exhibitors at nin...
Kulkarni MA, Berrang-Ford L, Buck PA, Drebot MA, Lindsay LR, Ogden NH.In Canada, the emergence of vector-borne diseases may occur via international movement and subsequent establishment of vectors and pathogens, or via northward spread from endemic areas in the USA. Re-emergence of endemic vector-borne diseases may occur due to climate-driven changes to their geographic range and ecology. Lyme disease, West Nile virus (WNV), and other vector-borne diseases were identified as priority emerging non-enteric zoonoses in Canada in a prioritization exercise conducted by public health stakeholders in 2013. We review and present the state of knowledge on the public heal...
Huang BF, Kropinski AM, Bujold AR, MacInnes JI.Actinobacillus equuli subsp. equuli is a member of the family Pasteurellaceae that is a common resident of the oral cavity and alimentary tract of healthy horses. At the same time, it can also cause a fatal septicemia in foals, commonly known as sleepy foal disease or joint ill disease. In addition, A. equuli subsp. equuli has recently been reported to act as a primary pathogen in breeding sows and piglets. To better understand how A. equuli subsp. equuli can cause disease, the genome of the type strain of A. equuli subsp. equuli, ATCC 19392(T), was sequenced using the PacBio RSII sequencing s...
Nixon J.Equine consultant, Jane Nixon, attended the first equine biosecurity course at the British Racing School in November last year, organised by Whorl Publishing. Here, she reports on some of the issues covered.
Dhama K, Kapoor S, Pawaiya RV, Chakraborty S, Tiwari R, Verma AK.A fascinating and important arbovirus is Ross River Virus (RRV) which is endemic and epizootic in nature in certain parts of the world. RRV is a member of the genus Alphavirus within the Semliki Forest complex of the family Togaviridae, which also includes the Getah virus. The virus is responsible for causing disease both in humans as well as horses. Mosquito species (Aedes camptorhynchus and Aedes vigilax; Culex annulirostris) are the most important vector for this virus. In places of low temperature as well as low rainfall or where there is lack of habitat of mosquito there is also limitatio...
Faverjon C, Leblond A, Hendrikx P, Balenghien T, de Vos CJ, Fischer EA, de Koeijer AA.African horse sickness (AHS) is a major, Culicoides-borne viral disease in equines whose introduction into Europe could have dramatic consequences. The disease is considered to be endemic in sub-Saharan Africa. Recent introductions of other Culicoides-borne viruses (bluetongue and Schmallenberg) into northern Europe have highlighted the risk that AHS may arrive in Europe as well. The aim of our study was to provide a spatiotemporal quantitative risk model of AHS introduction into France. The study focused on two pathways of introduction: the arrival of an infectious host (PW-host) and the arri...
Badenhorst M, Page P, Ganswindt A, Laver P, Guthrie A, Schulman M.The prevalence of equine herpesvirus types-1 and -4 (EHV-1 and -4) in South African Thoroughbreds at auction sales is currently undefined. Commingling of young Thoroughbreds from various populations together with physiological stress related to their transport and confinement at a sales complex, may be associated with shedding and transmission of EHV-1 and -4. This prospective cohort study sampled 90 young Thoroughbreds consigned from eight farms, originating from three provinces representative of the South African Thoroughbred breeding demographic to a sales complex. Nasal swabs for quantitat...
Edson D, Field H, McMichael L, Jordan D, Kung N, Mayer D, Smith C.Bats of the genus Pteropus (flying-foxes) are the natural host of Hendra virus (HeV) which periodically causes fatal disease in horses and humans in Australia. The increased urban presence of flying-foxes often provokes negative community sentiments because of reduced social amenity and concerns of HeV exposure risk, and has resulted in calls for the dispersal of urban flying-fox roosts. However, it has been hypothesised that disturbance of urban roosts may result in a stress-mediated increase in HeV infection in flying-foxes, and an increased spillover risk. We sought to examine the impact of...
Fall M, Fall AG, Seck MT, Bouyer J, Diarra M, Balenghien T, Garros C, Bakhoum MT, Faye O, Baldet T, Gimonneau G.Culicoides biting midges (Diptera: Ceratopogonidae) are important vectors of arboviruses in Africa. Culicoides oxystoma has been recently recorded in the Niayes region of Senegal (West Africa) and its high abundance on horses suggests a potential implication in the transmission of the African horse sickness virus in this region. This species is also suspected to transmit bluetongue virus to imported breeds of sheep. Little information is available on the biology and ecology of Culicoides in Africa. Therefore, understanding the circadian host-seeking activity of this putative vector is of prima...
May CE, Guthrie AJ, Keys B, Joone C, Monyai M, Schulman ML.The response to the first outbreak of contagious equine metritis in South Africa included pioneering a web-based platform to coordinate key aspects of a national, real-time polymerase chain reaction (qPCR)-based stallion screening programme to determine the distribution and prevalence of Taylorella equigenitalis in stallions and exposed mares. Objective: To define the hypothesised pre-existing status of T. equigenitalis in the South African equine population and progression of the epidemiological investigation via the implementation of a molecular diagnostic-based surveillance programme. Metho...
López RH, Soto SU, Gallego-Gómez JC.West Nile virus (WNV) is a member of the genus Flavivirus, and it is transmitted between Culex sp. mosquitoes and avian hosts. Equids and humans are commonly infected with WNV as dead-end hosts, and the signs and symptoms of infection range from mild illness to neurologic symptoms as encephalitis, meningitis and sometimes death. Previous phylogenetic studies have classified WNV into six genetically distinct lineages and provided valuable insight on WNV dispersal patterns within the Americas and its emergence in different geographic areas. In this study, we isolated, sequenced and genetically c...
Abdel-Ghaffar F, Al-Quraishy S, Mehlhorn H.The present study had the aim to test the repellent potential of the compound icaridin = Saltidin® against the tick species Ixodes ricinus and Ixodes persulcatus using different formulations of the compound. Tests were done on backs of impregnated human hands, on impregnated linen cloth and versus impregnated dog hair. It was found that 1. Ixodes persulcatus-the common Eastern European, Russian Ixodes species is significantly sensitive to icaridin = Saltidin® as I. ricinus protecting for the test period of 5 h. This is an important finding, since I. persulcatus is the vector of agents of the...
Hale D.West Nile Virus is the most frequent cause of arboviral disease in the United States. It was first identified in the United States in 1999. Since that time, each of the 48 contiguous states in the United States has seen the disease, and it has been found in 96% of the U.S. counties in infected humans, mosquitoes, birds, horses, or other mammals. Although most often the disease resolves on its own, patients can develop serious and life-threatening complications, and may need further monitoring and treatment. This article reviews the prevalence, transmission, signs and symptoms, complications, t...
Jakobsen L, Bortolaia V, Bielak E, Moodley A, Olsen SS, Hansen DS, Frimodt-Møller N, Guardabassi L, Hasman H.CTX-M-1 is a common extended-spectrum β-lactamase (ESBL) in Escherichia coli from animals and is often detected among human clinical isolates. The objective of this study was to investigate the epidemiological relationship between CTX-M-1-producing E. coli isolated from patients and animals in Denmark between 2006 and 2010. In total, 65 CTX-M-1-producing isolates from patients (n=22), pigs (n=21), cattle (n=4), organic poultry layers (n=3) and horses (n=15) were typed by pulsed-field gel electrophoresis (PFGE). Plasmids harbouring bla were characterised by S1 PFGE, PCR-based replicon typing, ...
Robin M, Archer D, McGowan C, Garros C, Gardès L, Baylis M.African horse sickness (AHS) is a vectorborne disease spread by Culicoides biting midges. The UK's Department for Environment, Food and Rural Affairs currently suggests using topical deltamethrin for AHS control; however, no data are available regarding its efficacy in the horse. The aims of this study were to investigate the effect of topical deltamethrin on blood feeding by Culicoides on horses and to investigate which Culicoides species blood fed on horses. Three pairs of horses were placed in partially enclosed cages that allowed samples representing the Culicoides interacting with individ...
Hara Y, Nakajima T, Akamatsu M, Yahiro M, Kagawa S, Petry S, Matsuda M, Moore JE.Contagious equine metritis is a bacterial infectious disease of horses caused by Taylorella equigenitalis, a Gram-negative eubacterium. The disease has been described in several continents, including Europe, North America and Asia. A novel molecular method was developed to detect clustered regularly interspaced short palindromic repeats (CRISPRs), which were separated by non-repetitive unique spacer regions (NRUSRs) of similar length, in the Taylorella equigenitalis EQ59 strain using a primer pair, f-/r-TeCRISPR-ladder, by PCR amplification. In total, 31 Taylorella isolates (17 T. equigenitali...
Hartmann FA, Callan RJ, McGuirk SM, West SE.Salmonella anatum was isolated from horses treated at a private veterinary clinic or at a university veterinary medical teaching hospital. All isolates were resistant to most commonly used antibiotics. Because of the severity of disease resulting from outbreaks of infections with drug-resistant strains of S anatum, an epidemiologic investigation was conducted. Enteric bacteria, including S anatum, that were resistant to most antibiotics were isolated from the private veterinary clinic environment. Salmonella anatum was not isolated from the university teaching hospital environment. To prevent ...
Riley RT, Showker JL, Owens DL, Ross PF.Fumonisin B(1), B(2), and B(3) are inhibitors of ceramide synthase, a key enzyme in the pathway for de novo sphingolipid biosynthesis. Corn, naturally contaminated with either predominantly fumonisin B(1) or pure fumonisin B(1), has been shown to cause equine leukoencephalomalacia (ELEM). It has been hypothesized that fumonisin-induced disruption of sphingolipid metabolism is an early event in the development of ELEM. Recently, it was shown that Fusarium proliferatum corn culture diets containing predominantly fumonisin B(2), but not diets which were predominantly fumonisin B(3), at 75 ppm (0....
Dorneles EMS, Santana JA, Costa ACTRB, Junqueira DG, Heinemann MB, Lage AP.Brucellosis in equines, including horses, donkeys, and mules, is characterized by abscesses in tendons, bursae, and joints. Reproductive disorders, which are common in other animals, are rare in both males and females. Joint breeding of horses, cattle, and pigs was found as the main risk factor for equine brucellosis, with the transmission from equines to cattle or among equines possible, although unlikely. Hence, evaluation of the disease in equines can be considered an indirect indicator of the effectiveness of brucellosis control measures employed for other domestic species. Generally, the ...
Abdullah HHAM, Elbayoumy MK, Allam AM, Ashry HM, Abdel-Shafy S.Vector-borne bacterial diseases (VBBD) are a diverse group of tropical and subtropical zoonotic diseases. This study investigated the possibility of domestic animals to carry certain vector-borne bacterial microorganisms (VBBMs), as well as the presence of these targeted DNAs in their ectoparasites in different localities of Egypt using molecular analyses. For this study, 234 animal hosts (112 cattle, 38 sheep, 28 goats, 26 buffaloes, 22 donkeys, and 8 horses) in addition to 115 ectoparasites (95 ticks and 20 lice) were investigated for the molecular detection of Bartonella spp., Borrelia spp....
Aslantas Ö, Türkyilmaz S, Yilmaz MA, Erdem Z, Demir C.The present study was carried out to assess the frequency of methicillin-resistant staphylococci (MRS) among racehorses (n=209) and veterinary personnel (n=13) as well as environmental surfaces (n=14) at an equine hospital in Adana, Turkey. In addition, species distribution, antimicrobial susceptibility, resistance genes, staphylococcal chromosomal cassette mec (SCCmec) type and clonality of these isolates were also investigated. MRS were identified by 16S rRNA sequencing, and typed by pulsed-field gel electrophoresis (PFGE). As a result, MRS was isolated in horses (48.3%), clinic staff (92.3%...
Selmi R, Dhibi M, Ben Said M, Ben Yahia H, Abdelaali H, Ameur H, Baccouche S, Gritli A, Mhadhbi M.Livestock constitute habitual hosts and carriers for several infectious pathogens which may represent a serious public health concern affecting the readiness of military forces and lead to wide economic losses. The present report aimed to investigate the prevalence of some haemopathogens infecting military livestock, particularly, dromedaries, sheep and horses using Giemsa-stained blood smears. A total of 300 animals (100 from each species) were selected, clinically examined and sampled. Trypanosoma spp. (22.0%), Anaplasma spp. (17.0%) and Babesia spp. (1.0%) were identified in camels' blood. ...
Sellers RF, Maarouf AR.Backward trajectories of winds were determined to identify possible sources of eastern equine encephalitis virus associated with isolation of virus from mosquitoes or birds or outbreaks in horses between 1980 and 1985 in Maryland, New Jersey, New York and Michigan, USA. The results of the trajectory analyses suggested that eastern equine encephalitis virus could have been carried by infected mosquitoes on surface winds at temperatures 13 degrees C or higher from North Carolina north-eastwards along the Atlantic Coast to Maryland and New Jersey and thence to upstate New York and from western Ke...
Reid SW, Gettinby G, Fowler JN, Ikin P.An epidemiological study of equine sarcoid in a population of 4126 donkeys showed that the peak incidence of the disease was 15.2 cases per 100 animal-years and occurred in animals in their fourth year of life. The crude incidence of the disease was 0.6 cases per 100 animal-years. The disease occurred most frequently in younger, male animals during their first five years in the population. The lesions were observed most commonly in the paragenital region. Pre-entry quarantine procedures did not appear to play a significant role in the spread of the disease but there was an indication that clos...
Wohlfender FD, Barrelet FE, Doherr MG, Straub R, Meier HP.The development of clinical illness in foals is usually predetermined by perinatal history, management or stressful environmental conditions. Objective: To determine potential risk factors for an increased incidence of infectious diseases during the first 30 days post partum. Methods: The population consisted of Thoroughbred foals born on stud farms in the Newmarket (UK) area in 2005 (n = 1031). They were followed for their first 30 days. Factors suspected to influence the incidence of infectious neonatal diseases were examined in a logistic regression approach for each of the 3 outcomes (tota...
Tartor YH, El-Naenaeey EY, Gharieb NM, Ali WS, Ammar AM.Strangles displays a major challenge to veterinary medicine worldwide. However, no data on Streptococcus equi subsp. equi (S. equi) M protein alleles have been reported so far from Arabian horses. We report here for the first time the S. equi SeM alleles causing strangles in Arabian horses, and the associated risk factors for the disease. Duplicate samples from one hundred Arabian horses with acute strangles in confirmed outbreaks and sporadic cases were analysed by phenotypic methods and multiplex polymerase chain reaction (PCR) targeting streptokinase precursor, seeI and sodA genes. PCR and ...
García-Romero C, Carrillo Bilbao GA, Navarro JC, Martin-Solano S, Saegerman C.Arthropod-borne viruses (arboviruses) are a diverse group of ribonucleic acid (RNA) viruses, with the exception of African swine fever virus, that are transmitted by hematophagous arthropods to a vertebrate host. They are the important cause of many diseases due to their ability to spread in different environments and their diversity of vectors. Currently, there is no information on the geographical distribution of the diseases because the routes of transmission and the mammals (wild or domestic) that act as potential hosts are poorly documented or unknown. We conducted a systematic review fro...
Godsey MS, Amoo F, Yuill TM, Defoliart GR.A serologic survey and experimental virus transmission studies were done to assess the role of domestic animals as amplifier hosts of La Crosse (LACV) and Jamestown Canyon (JCV) viruses. Serum from 319 cows, 88 dogs, 122 equines, 47 swine, 10 goats, and 4 cats were tested for neutralizing antibody to LACV, JCV, trivittatus (TVTV), and snowshoe hare (SSHV) viruses. Antibody prevalences of LACV, TVTV, and SSHV were less than 10% in all species. Antibody to JCV was detected in all species except cats. Prevalence ranged from 10% in goats and swine to 29% in dogs. No age-associated trends in JCV pr...
de Siqueira SM, da Costa Maia R, do Nascimento Ramos V, da Silva Rodrigues V, Szabó MPJ.We herein describe zebuine cattle tick infestation in a farm in southeast Brazil with an examination accurate enough to detect tick immatures and species other than R. microplus. Cattle were inspected monthly for ticks from May 2015 to May 2017 and 7604 ticks were collected along 276 bovine inspections. Rhipicephalus microplus was the dominant species (7197 specimens, 94.5% from the total), but Amblyomma sculptum was also collected (407/5.5%). Horse tick infestations were evaluated for comparison purposes of A. sculptum infestations of a primary host sharing pastures with bovines. Ticks were c...
Paruch L, Paruch AM.Zoogenic faecal contamination of the environment is one of the indices included in the evaluation of ecological threats, health hazards and adverse impacts on various ecosystems. The risks and environmental concerns are associated with the fact that faeces of wild and domesticated animals constitute the largest source of environmental loading of enteropathogens associated with transmission of zoonotic diseases (enteric zoonoses). Although sick animals are more likely to transmit pathogens, healthy ones can also be the carriers and defecate them into the environment. This is of particular impor...
Rockx B, van Asten L, van den Wijngaard C, Godeke GJ, Goehring L, Vennema H, van der Avoort H, van Pelt W, Koopmans M.West Nile virus (WNV) is an arthropod-borne flavivirus that is endemic in Africa, Europe, and Eastern Asia. The recent introduction and rapid dissemination of the virus in the United States as well as an increase in WNV outbreaks in Europe, has raised concerns for its spread in Europe. A surveillance system was developed to allow timely detection of an introduction of WNV infections in The Netherlands. This program focuses on cases presenting with neurological disease and includes the monitoring of hospital discharge diagnoses, trends in cerebrospinal fluid (CSF) diagnostic requests, laborator...
Nishiura H, Satou K.An outbreak of equine influenza (H3N8) occurred among fully vaccinated racehorses in Japan from August to September, 2007. To assess the potential effectiveness of public health interventions other than vaccination (i.e. movement restriction, isolation and quarantine), which started immediately on the date of detection of the first febrile case, a simple epidemiological model was developed and applied to the observed data. The epidemic curves in five racehorse facilities revealed consistent temporal patterns: (i) a sharp increase in symptom onset of cases during the first 3 days, which is thou...
Burkett-Cadena ND, Day JF, Unnasch TR.Eastern equine encephalitis virus (EEEV; family Togaviridae, genus Alphavirus) is a mosquito-borne pathogen found in eastern North America that causes severe disease in humans and horses. The mosquito Culiseta melanura (Coquillett) (Diptera: Culicidae) is the primary enzootic vector of EEEV throughout eastern North America while several mosquito species belonging to diverse genera serve as bridge vectors. The ecology of EEEV differs between northern and southern foci, with respect to phenology of outbreaks, important vertebrate hosts, and bridge vector species. Active transmission is limited t...
Ward MP, Wittich CA, Fosgate G, Srinivasan R.West Nile Virus (WNV) was first detected in the Texas equine population during June 2002. Infection has since spread rapidly across the state and become endemic in the equine population. Environmental risk factors associated with equine WNV attack rates in Texas counties during the period 2002 to 2004 were investigated. Equine WNV attack rates were smoothed using an empirical Bayesian model, because of the variability among county equine populations (range 46-9,517). Risk factors investigated included hydrological features (lakes, rivers, swamps, canals and river basins), land cover (tree, mos...
Williams DL, Issel CJ, Steelman CD, Adams WV, Benton CV.Biological and mechanical transmission trials with Psorophora columbiae (Dyar and Knab) and Aedes sollicitans (Walker) and ponies acutely infected with equine infectious anemia virus (EIAV) were negative. The EIAV antigen was detected by radioimmunoassay in Ae sollicitans immediately after the mosquitoes had fed on an acutely ill pony, but not 14 days after feeding. Psorophora columbiae mosquitoes had detectable EIAV antigen as determined by radioimmunoassay 24 hours after they fed on an acutely ill pony; this antigen was not detected again until 6 days after feeding and was still detected 14 ...
Vander Kelen PT, Downs JA, Stark LM, Loraamm RW, Anderson JH, Unnasch TR.Eastern Equine Encephalitis virus (EEEV) is an alphavirus with high pathogenicity in both humans and horses. Florida continues to have the highest occurrence of human cases in the USA, with four fatalities recorded in 2010. Unlike other states, Florida supports year-round EEEV transmission. This research uses GIS to examine spatial patterns of documented horse cases during 2005-2010 in order to understand the relationships between habitat and transmission intensity of EEEV in Florida. Methods: Cumulative incidence rates of EEE in horses were calculated for each county. Two cluster analyses wer...
Barnard BJ.The entry of Culicoides species into stables was examined by comparing the numbers of midges caught with identical light-traps under different conditions. The comparison was made between collections made inside an empty stable, a regularly cleaned stable and a dirty stable and those made outside the stables in a sleeping space open on two sides. The work was first done in the presence of cattle and sheep in adjoining paddocks and then repeated in their absence. A positive correlation was found between the numbers of C. imicola females caught out of doors and inside a clean stable. Removal of t...
Stockton KA, Morley PS, Hyatt DR, Burgess BA, Patterson G, Dunowska M, Lee DE.To evaluate the effects of footwear hygiene protocols on bacterial contamination of floor surfaces in an equine hospital. Methods: Field trial. Methods: Footwear hygiene protocols evaluated included use of rubber overboots with footbaths and footmats containing a quaternary ammonium disinfectant, rubber overboots with footbaths and footmats containing a peroxygen disinfectant, and no restrictions on footwear type but mandatory use of footbaths and footmats containing a peroxygen disinfectant. Nonspecific aerobic bacterial counts were determined via 2 procedures for sample collection and bacter...
Marchi PR, Rawlings P, Burroughs JN, Wellby M, Mertens PP, Mellor PS, Wade-Evans AM.Purified African horse sickness virus (AHSV) was fed, as part of a blood meal, to adult females from a susceptible colony of Culicoides variipennis, established in the insectories at the Institute for Animal Health, Pirbright Laboratory, UK. The meal consisted of heparinized blood obtained from ovine, bovine, equine (horse and donkey) or canine sources spiked with AHSV serotype 9 (AHSV9). The infectivity levels observed for C. variipennis varied significantly, according to the source of the blood sample. Comparison of the protein profiles obtained from AHSV9 incubated with the individual serum...
Hayama Y, Kobayashi S, Nishida T, Muroga N, Tsutsui T.An equine infectious anemia (EIA) transmission model was developed by constructing a network structure of horse movement patterns in a non-racehorse population. This model was then used to evaluate the effectiveness and efficiency of several EIA surveillance strategies. Because EIA had not been detected in Japan since 1993, it was appropriate to review the current surveillance strategy, which aims to eradicate EIA by intensive testing, and to consider alternative strategies suitable for the current EIA status in Japan. The non-racehorse population was divided into four sectors based on horse u...
Ribeiro MF, da Silveira JA, Bastos CV.Tick-borne diseases in horses are caused by the intraerythrocytic protozoan parasites Theileria equi and Babesia caballi. Although T. equi is highly endemic in Latin America, the New World vector of this important parasite is controversial. The aim of this study was to test the ability of nymph Amblyomma cajennense ticks acquire infection by T. equi following feeding on infected horses. Three experiments were performed: tick acquisition of T. equi from an experimentally infected horse, tick acquisition of T. equi from naturally infected foals and tick acquisition of T. equi from a chronically ...
de Niederhäusern S, Sabia C, Messi P, Guerrieri E, Manicardi G, Bondi M.Vancomycin-resistant enterococci (VRE) in healthy people and in food-producing animals seems to be quite common in Europe. The existence of this community reservoir of VRE has been associated with the massive use of avoparcin in animal husbandry. Eight years after the avoparcin ban in Europe, we investigated the incidence of VanA enterococci, their resistance patterns, and the mobility of their glycopeptide-resistance determinants in a sampling of animal rectal swabs and clinical specimens. A total of 259 enterococci isolated from equine, swine, and clinical samples were subcultured on KF-stre...
Weese JS.Because nosocomial and zoonotic diseases are inherent and ever-present risks in veterinary hospitals, proactive policies should be in place to reduce the risk of sporadic cases and outbreaks. Policies should ideally be put in place before disease issues arise, and policies should be effectively conveyed to all relevant personnel. Written policies are required for practical and liability reasons and should be reviewed regularly. Although no infection control program can eliminate disease concerns, proper implementation of barrier precautions and isolation can reduce the exposure of hospitalized...
Coultous RM, Leadon DP, Shiels BR, Sutton D, Weir W.Equine piroplasmosis (EP) is a notifiable disease in Ireland and a significant concern to domestic and international equine industries. Information regarding EP presence in Ireland is currently limited. This retrospective surveillance study describes a serological and molecular analysis of blood samples submitted to the Irish Equine Centre for EP testing between January 2013 and April 2016. Methods: Following serological testing, seropositive samples were screened using a PCR targeting the 18S ribosomal RNA gene. Amplicon sequences were bioinformatically analysed to identify the parasite speci...
Medina-Torres CE, Weese JS, Staempfli HR.Clostridium difficile infection (CDI) is a recognized cause of colitis in the horse. Identification of its toxins is important for management of individual cases and for prevention of transmission and zoonosis. In humans, CDI diagnosis is performed with enzyme immunoassays, none of which have been validated for horses. Objective: (1) Establish which test for CDI diagnosis was more frequently used by diagnostic laboratories, (2) determine the identified test's performance, sensitivity, and specificity, and (3) validate its use in diarrheic horses. Methods: Samples were obtained from 72 horses p...
Ceylan O, Benedicto B, Ceylan C, Tumwebaze M, Galon EM, Liu M, Xuan X, Sevinc F.Common vector-borne diseases of horses include equine piroplasmosis (EP) caused by Babesia caballi and Theileria equi, and equine granulocytic anaplasmosis (EGA) caused by Anaplasma phagocytophilum. Equine piroplasmosis leads to severe health issues in horses and restrictions on the movement of horses internationally. Anaplasma phagocytophilum causes an acute febrile illness in horses and is also of zoonotic importance. In the present study, blood samples were collected from 152 Turkish racehorses from three different provinces (İzmir, Gaziantep, and Konya) of Turkey to investigate the preval...
