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.
Boyle AG, O'Shea K, Stefanovski D, Rankin SC.There is debate around the clinical significance of Streptococcus equi subsp. equi detection in low numbers using quantitative real-time PCR (qPCR). Propidium monoazide (PMA) qPCR has been used to differentiate DNA from viable and nonviable bacterial cells. The aim of this study was to evaluate the ability of PMA eqbE SEQ2190 triplex qPCR to differentiate DNA from viable and nonviable S. equi in positive and suspect positive clinical specimens. Fifty-seven stored (frozen and refrigerated) positive (36) or suspect positive (21) clinical specimens (determined via SeeI qPCR as the gold standard) ...
Legere RM, Allegro AR, Affram Y, Silveira BPD, Fridley JL, Wells KM, Oezguen N, Burghardt RC, Wright GA, Pollet J, Bordin AI, Figueiredo P....To examine the susceptibility of cultured primary equine bronchial epithelial cells (EBECs) to a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pseudovirus relative to human bronchial epithelial cells (HBECs). Methods: Primary EBEC cultures established from healthy adult horses and commercially sourced human bronchial epithelial cells (HBECs) were used as a positive control. Methods: Angiotensin-converting enzyme 2 (ACE2) expression by EBECs was demonstrated using immunofluorescence, western immunoblot, and flow cytometry. EBECs were transduced with a lentivirus pseudotyped with ...
Li H, Kim JV, Pickering BS.Hendra virus (HeV) and Nipah virus (NiV) are biosafety level 4 zoonotic pathogens causing severe and often fatal neurological and respiratory disease. These agents have been recognized by the World Health Organization as top priority pathogens expected to result in severe future outbreaks. HeV has caused sporadic infections in horses and a small number of human cases in Australia since 1994. The NiV Malaysia genotype (NiV-M) was responsible for the 1998-1999 epizootic outbreak in pigs with spillover to humans in Malaysia and Singapore. Since 2001, the NiV Bangladesh genotype (NiV-B) has been t...
Sewgobind S, McCracken F, Schilling M.West Nile virus (WNV) is a positive-sense single-stranded RNA virus belonging to the Flaviviridae family and is maintained in an enzootic cycle between avian hosts and mosquito vectors. Humans, horses and other mammals are susceptible to infection but are dead-end hosts due to a low viraemia. The disease can manifest itself in a variety of clinical signs and symptoms in people and horses from mild fever to severe encephalitis and morbidity. There are no vaccines licensed for human protection, but parts of Europe, North America, Africa and Australia have vaccines commercially available for hors...
Pearson GB, Papa B, Mosaddegh A, Cooper H, Aprea M, Pigott J, Altier C, Cazer CL, Reesink HL.To investigate (1) variables associated with the likelihood of obtaining a positive culture, (2) commonly isolated microorganisms, and (3) antimicrobial resistance patterns of isolates from horses with presumptive synovial sepsis. Methods: Synovial fluid, synovium, and bone samples from equine cases with presumptive synovial sepsis submitted to the Cornell University Animal Health Diagnostic Center from 2000 to 2020 for microbial culture and antimicrobial sensitivity testing. Methods: Univariable and multivariable analyses were performed to determine the effect of variables on the likelihood o...
Holguin-Rocha AF, Calle-Tobon A, Vásquez GM, Astete H, Fisher ML, Tobon-Castano A, Velez-Tobon G, Maldonado-Ruiz LP, Silver K, Park Y....Ticks are obligatory hematophagous ectoparasites that transmit pathogens among various vertebrates, including humans. The microbial and viral communities of ticks, including pathogenic microorganisms, are known to be highly diverse. However, the factors driving this diversity are not well understood. The tropical horse tick, Dermacentor nitens, is distributed throughout the Americas and it is recognized as a natural vector of Babesia caballi and Theileria equi, the causal agents of equine piroplasmosis. In this study, we characterized the bacterial and viral communities associated with partial...
Gonzálvez M, Franco JJ, Barbero-Moyano J, Caballero-Gómez J, Ruano MJ, Martínez R, Cano-Terriza D, García-Bocanegra I.The largest epidemic of West Nile virus (WNV) reported ever in Spain in both humans and equines occurred in 2020, affecting 77 humans and 139 equine herds. Here, we aimed to monitor the outbreaks detected in equid herds in Andalusia (southern Spain), the Spanish region where 89.9% of the outbreaks were reported, and to evaluate the virus circulation and risk factor associated with WNV exposure in the affected herds. The first WNV case was detected in mid-July 2020, the number of outbreaks peaked in mid-August and the last one was confirmed on 26th October 2020. WNV lineage 1 was detected in 12...
Montaner-Angoiti E, Llobat L.Leishmania is a genus of parasitic protozoa that causes a disease called leishmaniasis. Leishmaniasis is transmitted to humans through the bites of infected female sandflies. There are several different species of Leishmania that can cause various forms of the disease, and the symptoms can range from mild to severe, depending on species of Leishmania involved and the immune response of the host. Leishmania parasites have a variety of reservoirs, including humans, domestic animals, horses, rodents, wild animals, birds, and reptiles. Leishmaniasis is endemic of 90 countries, mainly in South Amer...
Fürstenau J, Richter MT, Erickson NA, Große R, Müller KE, Nobach D, Herden C, Rubbenstroth D, Mundhenk L.Borna disease is a progressive meningoencephalitis caused by spillover of the Borna disease virus 1 (BoDV-1) to horses and sheep and has gained attention due to its zoonotic potential. New World camelids are also highly susceptible to the disease; however, a comprehensive description of the pathological lesions and viral distribution is lacking for these hosts. Here, the authors describe the distribution and severity of inflammatory lesions in alpacas ( = 6) naturally affected by this disease in comparison to horses ( = 8) as known spillover hosts. In addition, the tissue and cellular distribu...
de Souza RP, Mousquer MA, Müller V, Barbosa JCR, Leite FPL, Guedes RMC, Curcio BDR, Nogueira CEW.The aim of the present study was to carry out a serological survey to identify the seroprevalence of Lawsonia intracellularis in six Thoroughbred farms in the Southern region of the state of Rio Grande do Sul, Brazil. During 2019 and 2020, blood samples from 686 Thoroughbred horses were obtained from six different breeding farms. Horses were divided into groups according to age: (1) broodmares (>5 years), (2) two-year-old foals, (3) yearlings, and (4) 0-6 months-old foals. Blood samples were collected by venipuncture of the external jugular vein. The detection of antibodies (IgG) against L. in...
Li L, Maboni G, Lack A, Gomez DE.Nontuberculous mycobacteria (NTM) infections are increasing in human and veterinary medicine. Although horses were initially thought to be resistant to NTM infection, reports of horses suffering from gastrointestinal, respiratory, and reproductive diseases associated with NTM have increased in the last few decades. The aim of this literature review is to summarize the mycobacteria species found in horses, describe clinical manifestations, diagnostic and treatment approaches, and public health concerns of NTM infection in horses. Clinical manifestations of NTM in horses include pulmonary diseas...
Wang XF, Zhang X, Ma W, Li J, Wang X.Equine infectious anemia virus (EIAV) is a member of the lentivirus genus in the Retroviridae family and is considered an animal model for HIV/AIDS research. An attenuated EIAV vaccine, which was successfully developed in the 1970s by classical serial passage techniques, is the first and only lentivirus vaccine that has been widely used to date. Restriction factors are cellular proteins that provide an early line of defense against viral replication and spread by interfering with various critical steps in the viral replication cycle. However, viruses have evolved specific mechanisms to overcom...
Gorji FF, Sadr S, Borji H.Eimeria is a genus of protozoan parasites that infect many animal species, including horses. We conducted a cross-sectional study of indigenous breeds of horses from the North and Northeast of Iran to establish the prevalence and distribution of Eimeria species. Methods: Using standard coprological techniques, 340 faecal samples from randomly selected horses (141 from North Iran and 199 from Northeast Iran) were examined for Eimeria oocyst. Results: Out of 340 samples, only three from north Iran were positive for coccidiosis. Infections occurred by Eimeria leuckarti. The mean intensity of oocy...
Hain-Saunders NMR, Knight DR, Bruce M, Byrne D, Riley TV.Clostridioides difficile poses an ongoing threat as a cause of gastrointestinal disease in humans and animals. Traditionally considered a human healthcare-related disease, increases in community-associated C. difficile infection (CDI) and growing evidence of inter-species transmission suggest a wider perspective is required for CDI control. In horses, C. difficile is a major cause of diarrhoea and life-threatening colitis. This study aimed to better understand the epidemiology of CDI in Australian horses and provide insights into the relationships between horse, human and environmental strains...
Papapetrou MA, Arroyo LG, Meister TL, Baird JD, Steinmann E, Lillie BN.Equine parvovirus-hepatitis (EqPV-H) was first reported from the serum and liver tissue of a horse diagnosed with Theiler's disease in the United States in 2018. Theiler's disease, also known as equine serum hepatitis, is a severe hepatitis with fulminant hepatic necrosis. The disease has most frequently been reported following the administration of equine-origin biological products; however, it has also been reported in in-contact horses with no prior biologic administration. EqPV-H has been detected in clinically healthy horses in North America (USA, Canada), Europe (Germany, Austria, Sloven...
Crosby B, Crespo ME.Venezuelan Equine Encephalitis Virus (VEEV) is the causative viral pathogen of Venezuelan Equine Encephalitis (VEE). Outbreaks frequently involve both equines – including horses, donkeys, mules, zebras – and humans. Outbreaks may range over a large geographic area and may last for several months to years. Sporadic epidemic outbreaks occur most commonly in Central and South America. VEEV exists as both a natural pathogen and a laboratory-developed biologic weapon. Outbreaks have been reported in several South and Central American countries, including Venezuela, Colombia, Peru, Ecuador, C...
Bromberger CR, Costa JR, Herman M, Hernandez JM, Albertino LG, Alves CEF, Borges AS, Oliveira-Filho JP.Aural plaques have been linked to Equus caballus papillomavirus (EcPV). Ten types of EcPVs have already been described; however, only EcPVs 1, 3, 4, 5, and 6 have been observed in association with aural plaques. Accordingly, the objective of this study was to evaluate the presence of EcPVs in equine aural plaque samples. A total of 29 aural plaque samples (from 15 horses) were collected and assessed for the presence of the DNA of these EcPVs by PCR. Additionally, 108 aural plaque samples used in previous research were evaluated for the presence of EcPVs 8 and 9. Previously described primers we...
Kašpárková N, Bártová E, Žákovská A, Budíková M, Sedlák K.Lyme disease, caused by some strains of bacterial spirochetes Borrelia burgdorferi sensu lato (Bbsl), affects humans but also domestic animals including horses. The primary pathogens in horses in Europe are B. afzelii, B. garinii and B. burgdorferi sensu stricto. To our knowledge, there are no data available on the seropositivity of B. burgdorferi s.l. in horses from the Czech Republic. In this country, horses are mainly used for sport, breeding, and recreational riding in areas where vectors of B. burgdorferi s.l. are present, which is why they are frequently at risk of infection. The aim of ...
Mohammed MN, Yasmin AR, Ramanoon SZ, Noraniza MA, Ooi PT, Ain-Najwa MY, Natasha JA, Nur-Fazila SH, Arshad SS, Mohammed HO.West Nile virus is a mosquito-borne neurotropic pathogen with a wide host range that constitutes a significant risk to public and animal health. There is limited information on WNV infection in domesticated mammals in Malaysia; however, current reports indicate infections in birds, macaques, bats and pigs from Malaysia. In this study, 203 serum samples from cattle, goats, and horses were tested for the presence of anti-WNV IgG using a competitive enzyme-linked immunosorbent assay (c-ELISA). Additionally, using one-step RT-PCR, nasopharyngeal swabs were analyzed for WNV RNA from all 203 animals...
Pearson GB, Ysebaert MP, Papa B, Reesink HL.This article, as part of the Currents in One Health series, reviews the current state of diagnostics for synovial sepsis. Synovial sepsis is a condition that affects veterinary and human medicine and requires coordinated efforts from both parties, as well as environmental considerations to accurately diagnose and preserve effective treatments. The article discusses best practices to identify the causative agent in septic synovitis, trends in bacterial identification and antimicrobial resistance patterns across common bacterial species, and a one-health perspective to optimize diagnostics acros...
Elata A, Galon EM, Moumouni PFA, Ybanez RHD, Mossaad E, Salces CB, Bajenting GP, Ybanez AP, Xuan X, Inoue N, Suganuma K.Animal trypanosomosis is one of the most important parasitic diseases significantly affecting the Philippine economy. It is considered by the government to be the second most important disease of livestock after fasciolosis. A PCR-based molecular survey for trypanosomes in different animals in Bohol, Philippines, was performed to assess the prevalence of trypanosomosis in the area during the rainy and dry season. Methods: A total of 269 blood samples were collected in two batches in rainy and dry season from different animal species in Ubay Stock Farm in Ubay, Bohol, the Philippines, including...
Onder Z, Yildirim A, Duzlu O, Ciloglu A, Yetismis G, Karabulut F, Inci A.This study was conducted to determine single nucleotide polymorphisms (SNPs) and the benzimidazole (BZ) resistance in strongyle nematode egg populations in horses using molecular techniques. A total of 200 fecal samples were collected from horses in 26 farms in two provinces (Kayseri and Nevşehir) of the Central Anatolia Region of Türkiye between May and August 2022. The flotation method was used to detect strongyle nematode eggs in the fecal samples of the horses. Afterward, strongyle nematode eggs were collected, and the allele-specific polymerase chain reaction (AS-PCR) technique was used...
Topp AK, Springer A, Mischke R, Rieder J, Feige K, Ganter M, Nagel-Kohl U, Nordhoff M, Boelke M, Becker S, Pachnicke S, Schunack B, Dobler G, Strube C.Tick-borne encephalitis virus (TBEV) is a tick-transmitted flavivirus, which can infect humans and animals, sometimes even with a fatal outcome. Since many decades, TBEV is endemic in southern Germany, while only sporadic occurrence has been noted in northern parts of the country so far. Nevertheless, autochthonous human clinical cases are increasing in the federal state of Lower Saxony in north-western Germany, and several natural foci of TBEV transmission have recently been detected in this federal state. In order to shed more light on the current distribution of TBEV in Lower Saxony, the pr...
Martins AV, Coelho AL, Corrêa LL, Ribeiro MS, Lobão LF, Palmer JPS, Moura LC, Molento MB, Barbosa ADS.The frequency of gastrointestinal parasites with an emphasis on Strongylus vulgaris was investigated among the Brazilian Pony breed kept on farms in the municipality of Teresópolis, state of Rio de Janeiro. Fecal samples were collected in three stud farms: A (n= 22 animals), B (n= 3), and C (n= 2). Fecal samples were subjected to the quantitative Mini-FLOTAC technique, using three different solutions, and to qualitative techniques. The parasite prevalence was found to be 81.4%. Eggs from strongylids were identified in 74% of the ponies. Eggs of Parascaris spp. were detected in 22.7% of the an...
Lazić S, Savić S, Petrović T, Lazić G, Žekić M, Drobnjak D, Lupulović D.The paper presents the findings of specific antibodies in the blood sera of donkeys against the following viruses: equine infectious anemia virus (EIAV), African horse sickness virus (AHSV), equine herpesvirus type 1 (EHV-1), equine influenza virus subtype H3N8 (EIV) and equine arteritis virus (EAV). The analyses were conducted during the year 2022. From a total of 199 donkeys bred in "Zasavica", blood was sampled from 53 animals (2 male donkeys and 51 female donkeys), aged 3 to 10 years. Specific antibodies against EIAV were not detected in any of the tested animals using the agar-gel immunod...
Langsjoen RM, Key A, Shariatzadeh N, Jackson CR, Mahmood F, Arkun K, Alexandrescu S, Solomon IH, Piantadosi A.Eastern equine encephalitis virus (EEEV) is a relatively little-studied alphavirus that can cause devastating viral encephalitis, potentially leading to severe neurological sequelae or death. Although case numbers have historically been low, outbreaks have been increasing in frequency and scale since the 2000 s. It is critical to investigate EEEV evolutionary patterns, especially within human hosts, to understand patterns of emergence, host adaptation, and within-host evolution. To this end, we obtained formalin-fixed paraffin-embedded tissue blocks from discrete brain regions from five contem...
Jaimes-Dueñez J, Jiménez-Leaño Á, Enrique-Niño S, Arias-Landazábal N, Bedoya-Ríos M, Rangel-Pachón D.Piroplasmosis and trypanosomiasis are debilitating diseases of great economic impact on the equine industry of Latin America. Considering the lack of studies in the northeastern part of Colombia, this study aimed to determine the epidemiological, clinical and genetic features associated with infection of the Babesia, Theileria, and Trypanosoma species in horses from this geographical area. Two hundred and eighty horses from the Arauca, Meta, and Santander departments were molecularly analyzed for infection with Babesia caballi, Theileria equi, Trypanosoma evansi, and Trypanosoma vivax. Further...
Nielsen MK, Leathwick DM, Sauermann CW.Over the past three decades, equine strongylid egg reappearance periods (ERPs) have shortened substantially for macrocyclic lactone anthelmintics. The ERPs of ivermectin and moxidectin were originally reported in the 8-10 and 12-16 week ranges, respectively, but several recent studies have found them to be around 4-5 weeks for both actives. This loss of several weeks of suppressed strongylid egg output could have substantial implications for parasite control. This study made use of a computer simulation model to evaluate the impact of shortened ERPs on the anthelmintic performance of ivermecti...
Couroucé A, Normand C, Tessier C, Pomares R, Thévenot J, Marcillaud-Pitel C, Legrand L, Pitel PH, Pronost S, Lupo C.A total of 752 horses were involved in the CES Valencia Spring Tour 2021. Due to an equine herpesvirus-1 (EHV-1) outbreak, the competition was cancelled and the site was locked down. The objective of this study was to describe epidemiological, clinical, diagnostic, and outcome data of the 160 horses remaining in Valencia. Clinical and quantitative polymerase chain reaction (qPCR) data were analysed for 60 horses in a retrospective case-control observational study. The risk of developing clinical manifestations was explored using a logistic regression approach. EHV-1 was detected by qPCR, genot...
Gysens L, Vanmechelen B, Maes P, Martens A, Haspeslagh M.Infection with bovine papillomavirus (BPV) types 1 and 2 results in the most common skin tumor of horses, termed equine sarcoid. The persistent and recurrent nature of this tumor stands in contrast to the regressive nature of BPV-1/- 2 induced cutaneous papillomas in cattle. The circulation of horse-specific BPV-1/- 2 variants within equine populations has been suggested as a possible explanation for the difference in clinical presentation of BPV-1/- 2 infection between horses and cattle. In order to investigate this hypothesis, we identified 98 complete BPV-1/- 2 genomes using a Nanopore ...
Komar N, Clark GG.West Nile virus (Flavivirus: Flaviviridae; WNV) has spread rapidly throughout the Caribbean Basin since its initial detection there in 2001. This report summarizes our current knowledge of WNV transmission in tropical America. Methods: We reviewed the published literature and consulted with key public health officials to obtain unpublished data. Results: West Nile virus infections first appeared in human residents of the Cayman Islands and the Florida Keys in 2001, and in apparently healthy Jamaican birds sampled early in 2002. Serologic evidence of WNV infection in 2002 was detected in horses...
Garmashova N, Atasheva S, Kang W, Weaver SC, Frolova E, Frolov I.The encephalitogenic New World alphaviruses, including Venezuelan (VEEV), eastern (EEEV), and western equine encephalitis viruses, constitute a continuing public health threat in the United States. They circulate in Central, South, and North America and have the ability to cause fatal disease in humans and in horses and other domestic animals. We recently demonstrated that these viruses have developed the ability to interfere with cellular transcription and use it as a means of downregulating a cellular antiviral response. The results of the present study suggest that the N-terminal, approxima...
Ewers C, Bethe A, Stamm I, Grobbel M, Kopp PA, Guerra B, Stubbe M, Doi Y, Zong Z, Kola A, Schaufler K, Semmler T, Fruth A, Wieler LH, Guenther S.To discern the relevance of ST648 extended-spectrum β-lactamase (ESBL)-producing Escherichia coli as a putative new group of multiresistant and extraintestinal pathogenic strains in animals, its frequency, ESBL types, antimicrobial resistance patterns and virulence gene (VG) profiles should be determined and compared with ST131 strains from the same collection of strains. Methods: ESBL-producing E. coli isolates (n = 1152), consecutively sampled from predominantly dogs, cats and horses between 2008 and 2011, were assigned to a phylogenetic group by PCR. Partial multilocus sequence typing was ...
Dick LK, Bernhard AE, Brodeur TJ, Santo Domingo JW, Simpson JM, Walters SP, Field KG.The purpose of this study was to examine host distribution patterns among fecal bacteria in the order Bacteroidales, with the goal of using endemic sequences as markers for fecal source identification in aquatic environments. We analyzed Bacteroidales 16S rRNA gene sequences from the feces of eight hosts: human, bovine, pig, horse, dog, cat, gull, and elk. Recovered sequences did not match database sequences, indicating high levels of uncultivated diversity. The analysis revealed both endemic and cosmopolitan distributions among the eight hosts. Ruminant, pig, and horse sequences tended to for...
Autorino GL, Battisti A, Deubel V, Ferrari G, Forletta R, Giovannini A, Lelli R, Murri S, Scicluna MT.During the late summer of 1998, veterinary authorities in Tuscany, Italy, received reports of cases of neurologic disease among horses residing in a large wetland area located in the provinces of Florence and Pistoia. West Nile virus was isolated from two of the six horses that died or were euthanized. A retrospective epidemiologic study identified 14 clinical neurologic cases that occurred from August 20 to October 6 (attack rate of 2.8%). A serologic survey conducted over a 700-km2 area in stables with and without apparent clinical cases confirmed a wider spread of the infection, with an ove...
Hu S, Vincenz C, Buller M, Dixit VM.Molluscum contagiosum virus proteins MC159 and MC160 and the equine herpesvirus 2 protein E8 share substantial homology to the death effector domain present in the adaptor molecule Fas-associated death domain protein (FADD) and the initiating death protease FADD-like interleukin-1beta-converting enzyme (FLICE) (caspase-8). FADD and FLICE participate in generating the death signal from both tumor necrosis factor receptor-1 (TNFR-1) and the CD-95 receptor. The flow of death signals from TNFR-1 occurs through the adaptor molecule tumor necrosis factor receptor-associated death domain protein (TRA...
Frost MJ, Zhang J, Edmonds JH, Prow NA, Gu X, Davis R, Hornitzky C, Arzey KE, Finlaison D, Hick P, Read A, Hobson-Peters J, May FJ, Doggett SL....To determine the cause of an unprecedented outbreak of encephalitis among horses in New South Wales, Australia, in 2011, we performed genomic sequencing of viruses isolated from affected horses and mosquitoes. Results showed that most of the cases were caused by a variant West Nile virus (WNV) strain, WNV(NSW2011), that is most closely related to WNV Kunjin (WNV(KUN)), the indigenous WNV strain in Australia. Studies in mouse models for WNV pathogenesis showed that WNV(NSW2011) is substantially more neuroinvasive than the prototype WNV(KUN) strain. In WNV(NSW2011), this apparent increase in vir...
Viana D, Blanco J, Tormo-Más MA, Selva L, Guinane CM, Baselga R, Corpa J, Lasa I, Novick RP, Fitzgerald JR, Penadés JR.Staphylococci adapt specifically to various animal hosts by genetically determined mechanisms that are not well understood. One such adaptation involves the ability to coagulate host plasma, by which strains isolated from ruminants or horses can be differentiated from closely related human strains. Here, we report first that this differential coagulation activity is due to animal-specific alleles of the von Willebrand factor-binding protein (vWbp) gene, vwb, and second that these vwb alleles are carried by highly mobile pathogenicity islands, SaPIs. Although all Staphylococcus aureus possess c...
Rogers GN, Pritchett TJ, Lane JL, Paulson JC.Human and animal (avian and equine) influenza A virus isolates of the H3 serotype exhibit marked differences in their ability to bind specific sialyloligosaccharide sequences that serve as cell surface receptor determinants (G. Rogers and J. Paulson, 1983, Virology 127, 361-373). Whereas human isolates of this subtype strongly agglutinate enzymatically modified human erythrocytes containing the terminal SA alpha 2,6Gal sequence, avian and equine isolates preferentially agglutinate erythrocytes bearing the SA alpha 2, 3Gal sequence. As shown in this report, a glycoprotein found in horse serum, ...
Montelaro RC, Parekh B, Orrego A, Issel CJ.The recurrent nature of equine infectious anemia has been attributed to relatively rapid antigenic variations in equine infectious anemia virus (EIAV) during persistent infection under selective immune pressures. This model was tested by serological and biochemical analysis of virus isolates recovered from separate febrile episodes in two experimentally infected ponies. Neutralization assays employing immune sera from the experimentally infected ponies demonstrated that distinct antigenic strains of virus predominate during sequential febrile episodes in a single pony. Analysis of the test str...
Schneider J, Kaaden O, Copeland TD, Oroszlan S, Hunsmann G.Two glycopolypeptides with molecular weights 160,000 and 120,000 (gp120) are regularly recognized by human immunodeficiency virus (HIV)-specific antisera in lysates of cells persistently infected with HIV. In the present study, gp120 was characterized as the major envelope glycopolypeptide of HIV. Gp120 was identified as the external viral glycoprotein by radiosequencing and by its presence in purified virus. However gp120 was predominantly shed as a soluble protein into the culture fluid. Furthermore gp120 was precipitated by sera from horses infected with equine infectious anaemia virus (EIA...
Barlough JE, Madigan JE, DeRock E, Bigornia L.A nested polymerase chain reaction for detecting Ehrlichia equi in horses and ticks (Ixodes pacificus) was developed. A major second-round PCR product of 928 bp could be readily visualized in ethidium bromide-stained agarose minigels. An internal probe was used to verify the identity of the amplified product by non-radioactive (digoxigenin-based) Southern blotting; additional confirmation was provided by DNA sequence analysis. A dilution study testing the sensitivity of the PCR indicated that DNA derived from 3 infected neutrophils was sufficient to generate a PCR signal. The specificity of t...
Nugent J, Birch-Machin I, Smith KC, Mumford JA, Swann Z, Newton JR, Bowden RJ, Allen GP, Davis-Poynter N.Equid herpesvirus 1 (EHV-1) can cause a wide spectrum of diseases ranging from inapparent respiratory infection to the induction of abortion and, in extreme cases, neurological disease resulting in paralysis and ultimately death. It has been suggested that distinct strains of EHV-1 that differ in pathogenic capacity circulate in the field. In order to investigate this hypothesis, it was necessary to identify genetic markers that allow subgroups of related strains to be identified. We have determined all of the genetic differences between a neuropathogenic strain (Ab4) and a nonneuropathogenic ...
Thouless ME, Bryden AS, Flewett TH, Woode GN, Bridger JC, Snodgrass DR, Herring JA.Human, piglet, mouse, foal, lamb, calf and rabbit rotaviruses all infected, but could not readily be subcultured in LLC MK2 cells. Cells infected with mouse and calf rotaviruses reacted by indirect immunofluorescence (FA) with convalescent serum from children, piglets, mice, foals, lambs, calves or rabbits, taken after rotavirus infection. Human, calf, piglet, mouse and foal rotaviruses reacted with human, calf, mouse, foal and lamb convalescent serum by complement fixation (CF). It was not possible to distinguish between different rotaviruses by CF or FA. Neutralization tests, however, detect...
Morales MA, Barrandeguy M, Fabbri C, Garcia JB, Vissani A, Trono K, Gutierrez G, Pigretti S, Menchaca H, Garrido N, Taylor N, Fernandez F, Levis S....West Nile virus (WNV) was isolated from the brains of 3 horses that died from encephalitis in February 2006. The horses were from different farms in central Argentina and had not traveled outside the country. This is the first isolation of WNV in South America.
Schmiedel J, Falgenhauer L, Domann E, Bauerfeind R, Prenger-Berninghoff E, Imirzalioglu C, Chakraborty T.Multiresistant Gram-negative bacteria producing extended-spectrum β-lactamases (ESBLs) are an emerging problem in human and veterinary medicine. This study focused on comparative molecular characterization of β-lactamase and ESBL-producing Enterobacteriaceae isolates from central Hesse in Germany. Isolates originated from humans, companion animals (dogs and cats) and horses. Results: In this study 153 (83.6%) of the human isolates (n = 183) and 163 (91.6%) of the animal isolates (n = 178) were confirmed as ESBL producers by PCR and subsequent sequencing of the PCR amplicons. Predomin...
Baptiste KE, Williams K, Willams NJ, Wattret A, Clegg PD, Dawson S, Corkill JE, O'Neill T, Hart CA.We determined the molecular characteristics of methicillin-resistant staphylococci from animals and staff at a small animal and equine hospital. Methicillin-resistant Staphylococcus aureus (MRSA) identical to human EMRSA-15 was found in dogs and hospital staff. In contrast, 5 distinct MRSA strains were isolated from horses but not from hospital staff.
Pelkonen S, Lindahl SB, Suomala P, Karhukorpi J, Vuorinen S, Koivula I, Väisänen T, Pentikäinen J, Autio T, Tuuminen T.Streptococcus equi subspecies zooepidemicus (S. zooepidemicus) is a zoonotic pathogen for persons in contact with horses. In horses, S. zooepidemicus is an opportunistic pathogen, but human infections associated with S. zooepidemicus are often severe. Within 6 months in 2011, 3 unrelated cases of severe, disseminated S. zooepidemicus infection occurred in men working with horses in eastern Finland. To clarify the pathogen's epidemiology, we describe the clinical features of the infection in 3 patients and compare the S. zooepidemicus isolates from the human cases with S. zooepidemicus isolates...
Wise LN, Kappmeyer LS, Mealey RH, Knowles DP.Equine piroplasmosis is caused by one of 2 erythrocytic parasites Babesia caballi or Theileria equi. Although the genus of the latter remains controversial, the most recent designation, Theileria, is utilized in this review. Shared pathogenesis includes tick-borne transmission and erythrolysis leading to anemia as the primary clinical outcome. Although both parasites are able to persist indefinitely in their equid hosts, thus far, only B. caballi transmits across tick generations. Pathogenesis further diverges after transmission to equids in that B. caballi immediately infects erythrocytes, wh...
Mehlhorn H, Schein E.The horse-parasitizing species Babesia equi Laveran, 1901 was redescribed as Theileria equi Mehlhorn, Schein 1998 and, thus, transferred from one valid genus to another. This transfer was needed since it turned out that this horse parasite showed the relevant characteristics of theilerians with regard to biological data, morphological features, biochemical properties, and molecular biological relationships.
Santín M.Cryptosporidium spp. are frequent parasites of livestock and companion animals, raising questions about the clinical significance of such infections. Cryptosporidium infections have a wide spectrum of clinical signs that can vary from asymptomatic to serious infection to death. In neonatal ruminants, cryptosporidiosis is considered an important disease characterised by diarrhoea and mortality. In companion animals most infections are asymptomatic but severe clinical illness has also been reported in dogs, cats and horses. In birds, three main clinical forms of cryptosporidiosis are primarily s...
Catlin BW.The clinical significance, Gram stain reaction, and genus affiliation of Gardnerella vaginalis have been controversial since Gardner and Dukes described the organism as the cause of "nonspecific vaginitis," a common disease of women which is now called bacterial vaginosis. The organism was named G. vaginalis when taxonomic studies showed that it was unrelated to bacteria in various genera including Haemophilus and Corynebacterium. Electron microscopy and chemical analyses have elucidated the organism's gram-variable reaction. Controversy over the etiology of bacterial vaginosis was largely res...
Murcia PR, Baillie GJ, Daly J, Elton D, Jervis C, Mumford JA, Newton R, Parrish CR, Hoelzer K, Dougan G, Parkhill J, Lennard N, Ormond D, Moule S....Determining the evolutionary basis of cross-species transmission and immune evasion is key to understanding the mechanisms that control the emergence of either new viruses or novel antigenic variants with pandemic potential. The hemagglutinin glycoprotein of influenza A viruses is a critical host range determinant and a major target of neutralizing antibodies. Equine influenza virus (EIV) is a significant pathogen of the horse that causes periodical outbreaks of disease even in populations with high vaccination coverage. EIV has also jumped the species barrier and emerged as a novel respirator...
Olson JG, Ksiazek TG, Gubler DJ, Lubis SI, Simanjuntak G, Lee VH, Nalim S, Juslis K, See R.Sera were collected from humans, cattle, horses, goats, ducks, chickens, wild birds, bats and rats in Lombok, Indonesia, and were tested by haemagglutination inhibition (HI) for antibodies to JE, ZIKA, CHIK and RR. Selected sera were tested by microneutralization tests for antibodies to the following viruses: JE, ZIKA, MVE, TMU, LGT, KUN, SEP, DEN-2, CHIK, RR, GET, SIN, BUN, BAT and BAK. Human sera had JE HI antibody in 135 (30%) of 446 tested. Neutralization tests indicated that DEN-2, ZIKA, TMU, KUN and SEP may have caused flavivirus infections. Antibodies to other arboviruses tested for wer...
Timoney JF.Streptococci pathogenic for the horse include S. equi (S. equi subsp. equi), S. zooepidemicus (S. equi subsp. zooepidemicus), S. dysgalactiae subsp. equisimilis and S. pneumoniae capsule Type III. S. equi is a clonal descendent or biovar of an ancestral S. zooepidemicus strain with which it shares greater than 98% DNA homology and therefore expresses many of the same proteins and virulence factors. Rapid progress has been made in identification of virulence factors and proteins uniquely expressed by S. equi. Most of these are expressed either on the bacterial surface or are secreted. Notable e...
Telford EA, Watson MS, Aird HC, Perry J, Davison AJ.The complete DNA sequence of equine herpesvirus 2 (EHV-2) strain 86/67 was determined. The genome is 184,427 bp in size and has a base composition of 57.5% G + C. Unusually for a herpesvirus, about a third of the sequence distributed in several large blocks appears not to encode proteins. The 79 open reading frames that were identified as probably polypeptide-coding are predicted to encode 77 distinct proteins. Amino acid sequence comparisons confirmed that EHV-2 is a gamma-herpesvirus that is genetically collinear with herpesvirus saimiri (HVS; a gamma 2-herpesvirus) and Epstein-Barr virus (E...
Criado-Fornelio A, Martinez-Marcos A, Buling-Saraña A, Barba-Carretero JC.Molecular epizootiology of piroplasmids (Babesia spp., Theileria spp.) and Hepatozoon canis was studied in mammals from southern Europe (mainly from Spain, but also from Portugal and France). Partial amplification and sequencing of the 18s rRNA gene was used for molecular diagnosis. In some particular cases (B. ovis and B. bovis) the complete 18s rRNA gene was sequenced. Blood samples were taken from domestic animals showing clinical symptoms: 10 dogs, 10 horses, 10 cows, 9 sheep and 1 goat. In addition, DNA samples were isolated from blood of 12 healthy dogs and from spleen of 10 wild red fox...
