Staphylococcus is a genus of bacteria commonly found on the skin and mucous membranes of horses. These bacteria can be part of the normal flora but may also act as opportunistic pathogens, leading to infections under certain conditions. In horses, Staphylococcus species can cause a range of infections, including skin infections, wound infections, and more severe conditions such as septicemia. The most frequently identified species in equine infections is Staphylococcus aureus, known for its ability to resist certain antibiotics, complicating treatment efforts. This page compiles peer-reviewed research studies and scholarly articles that explore the epidemiology, pathogenic mechanisms, and treatment strategies of Staphylococcus infections in horses.
Freeland RB, Morello SL, DeLombaert M, Rajamanickam V.To quantify the influence of intravenous regional limb perfusion (IVRLP) with amikacin on bacterial bioburden in limb wounds. Methods: In vivo, experimental. Methods: Four adult horses. Methods: Full thickness wounds created on each dorsal metacarpus were inoculated with Staphylococcus aureus. One forelimb was randomly assigned to cephalic vein IVRLP with amikacin on days 2, 3, and 4 post-wounding. Biopsies on day 2 prior to IVRLP, and on days 5 and 8 were cultured to quantify wound bioburden (CFU/g). Two horses repeated the study in a crossover design, receiving IVRLP on the opposite limb (n...
Kelmer G, Tatz AJ, Kdoshim E, Britzi M, Segev G.This prospective experimental study goal was to determine the pharmacokinetics of imipenem after intravenous regional limb perfusion (IV-RLP) in standing horses. Nine horses participated in the study; that was approved by the University Animal Care and Use Committee. One thoracic limb or one pelvic limb of each horse was randomly selected. After the veins were catheterized, an Esmarch bandage tourniquet was applied and the catheter was injected with a solution containing 500mg of imipenem. Synovial fluid samples were collected from the fetlock joint and blood samples were collected from the ju...
Barceló Oliver F, Russell TM, Uprichard KL, Neil KM, Pollock PJ.To describe the clinical signs, surgical treatment, and outcome of septic arthritis of the coxofemoral joint in foals. Methods: Retrospective clinical study. Methods: Foals (n = 12) with confirmed sepsis of the coxofemoral joint. Methods: Lameness was localized to the coxofemoral joint based on physical examination. Sepsis was confirmed by cytological analysis of synovial fluid obtained under ultrasonographic guidance, during general anesthesia or standing sedation. Intra-articular analgesia was used as an adjunct diagnostic modality in 2 foals. Surgical lavage of the affected joint was pe...
Koop G, Vrieling M, Storisteanu DM, Lok LS, Monie T, van Wigcheren G, Raisen C, Ba X, Gleadall N, Hadjirin N, Timmerman AJ, Wagenaar JA, Klunder HM....Bicomponent pore-forming leukocidins are a family of potent toxins secreted by Staphylococcus aureus, which target white blood cells preferentially and consist of an S- and an F-component. The S-component recognizes a receptor on the host cell, enabling high-affinity binding to the cell surface, after which the toxins form a pore that penetrates the cell lipid bilayer. Until now, six different leukocidins have been described, some of which are host and cell specific. Here, we identify and characterise a novel S. aureus leukocidin; LukPQ. LukPQ is encoded on a 45 kb prophage (ΦSaeq1) found i...
Fratto MA, Hart KA, Norton NA, Barton MH, Giguère S, Hurley DJ.Cortisol is a key anti-inflammatory hormone that increases in bacterial sepsis and circulates predominantly bound to cortisol binding globulin (CBG). Only unbound cortisol was believed to be biologically active, but recent evidence suggests that CBG-bound cortisol also regulates inflammation. The objective of this study was to evaluate the effects of free and CBG-bound cortisol on equine neutrophil function ex vivo. We hypothesized that CBG would enhance cortisol-mediated suppression of neutrophil pro-inflammatory responses. Neutrophils isolated from 8 foals and 6 adult horses were exposed to ...
Polasek TCM, Kozicki LE, Pedrosa VB, Weiss RR, Bertol MAF, Camargo CE, Talini R.This study aimed to correlate the inflammatory reaction (IR) caused by a progesterone-releasing intravaginal device (P4) with ovarian activity and pregnancy rate (PR) in embryo-recipient anestrus mares (to decrease the spring transitional period). 50 animals were assigned to three groups: GP4 (P4 group; n = 16), GP4OH (P4 + oxytetracycline hydrochloride and hydrocortisone sprayed onto the device; n = 14), and GNP4 (no intravaginal P4; n = 20). The administration protocol for GP4 was: Day 0, 750 mg P4 + ovarian examination by ultrasonography (US) + vaginal sample collection; Day 8, US;...
Sharma M, Nunez-Garcia J, Kearns AM, Doumith M, Butaye PR, Argudín MA, Lahuerta-Marin A, Pichon B, AbuOun M, Rogers J, Ellis RJ, Teale C, Anjum MF.In recent years, there has been an increase in the number of livestock-associated methicillin resistant Staphylococcus aureus (LA-MRSA) clonal complex (CC) 398 recovered from S. aureus isolated animals in the UK. To determine possible origins of 12 LA-MRSA CC398 isolates collected after screening more than a thousand S. aureus animal isolates from the UK between 2013 and 2015, whole genome sequences (WGS) of CC398 European, including UK, and non-European isolates from diverse animal hosts were compared. Phylogenetic reconstruction applied to WGS data to assess genetic relatedness of all 89 iso...
Harvey A, Kilcoyne I, Byrne BA, Nieto J.To compare synovial concentrations of amikacin following intravenous regional limb perfusion (IVRLP) with two different doses, and to compare their ability to reach target concentrations for bacterial isolates from common orthopedic conditions. Methods: Randomized crossover experiment. Methods: Six adult horses. Methods: Horses received IVRLP with 2 and 3 g of amikacin in the cephalic vein of alternate limbs (20 minutes tourniquet application and ≥14 days washout period). Amikacin concentrations were quantified in synovial fluid collected from the middle carpal and metacarpophalangeal joints...
Ludwig EK, Brandon Wiese R, Graham MR, Tyler AJ, Settlage JM, Werre SR, Petersson-Wolfe CS, Kanevsky-Mullarky I, Dahlgren LA.To investigate the serum and synovial fluid serum amyloid A (SAA) response in equine models of synovitis and septic arthritis and to compare handheld and validated immunoturbidometric assays for SAA quantification. Methods: Controlled, experimental study. Methods: Healthy adult horses (n = 9). Methods: Synovitis (n = 4) and septic arthritis (n = 5) were induced using lipopolysaccharide and Staphylococcus aureus, respectively, and serial serum and synovial fluid samples were collected. Serial synovial fluid cytology was performed for both models and synovial fluid from the septic ar...
van Spijk JN, Schmitt S, Fürst AE, Schoster A.Antimicrobial resistance has become an important concern in veterinary medicine. The aim of this study was to describe the rate of antimicrobial resistance in common equine pathogens and to determine the occurrence of multidrug-resistant isolates. A retrospective analysis of all susceptibility testing results from bacterial pathogens cultured from horses at the University of Zurich Equine Hospital (2012-2015) was performed. Strains exhibiting resistance to 3 or more antimicrobial categories were defined as multidrug-resistant. Susceptibility results from 303 bacterial pathogens were analyzed, ...
Robinson CS, Timofte D, Singer ER, Rimmington L, Rubio-Martínez LM.Bacterial culture and antimicrobial susceptibility testing of septic synovial samples allows instigation of targeted antimicrobial therapy; however, bacterial culture takes more than 24 h and has low sensitivity. This study aimed to identify the most frequently cultured bacteria and their antimicrobial susceptibility profile from septic synovial samples in our referral equine hospital, to allow recommendations regarding appropriate initial antimicrobial therapy prior to culture results. Hospital records for all horses with synovial sepsis and a synovial sample submitted to the microbiology l...
Colbath AC, Wittenburg LA, Gold JR, McIlwraith CW, Moorman VJ.To determine the effect of intravenous regional limb perfusion (IVRLP) with a combination of mepivacaine hydrochloride and amikacin sulfate on synovial fluid amikacin sulfate concentration, antimicrobial activity, and mechanical nociceptive threshold (MNT). Methods: Experimental study. Methods: Healthy adult horses (n=9). Methods: One IVRLP treatment was randomly administered by cephalic vein of each limb: amikacin alone (1 g amikacin in 60 mL saline) or amikacin with mepivacaine (1 g amikacin and 500 mg mepivacaine in 60 mL saline). Opposite treatments were repeated after a 24 hour wash-out p...
Carmalt JL, Johanssen B, Waldner C.To compare the performance of horses with intermittent dorsal displacement of the soft palate (IDDSP) treated surgically with a control group and to determine whether there was a difference in postoperative performance between horses treated with a staphylectomy or a tie-forward procedure. Methods: A retrospective observational study. Methods: Swedish Warmblood trotting horses (Standardbreds) with endoscopically confirmed IDDSP (n=56) and control horses (n=48) with endoscopically normal upper airways tested using overground endoscopy identified from medical records. Methods: Generalized estima...
Olofsson TC, Butler É, Lindholm C, Nilson B, Michanek P, Vásquez A.In the global perspective of antibiotic resistance, it is urgent to find potent topical antibiotics for the use in human and animal infection. Healing of equine wounds, particularly in the limbs, is difficult due to hydrostatic factors and exposure to environmental contaminants, which can lead to heavy bio-burden/biofilm formation and sometimes to infection. Therefore, antibiotics are often prescribed. Recent studies have shown that honeybee-specific lactic acid bacteria (LAB), involved in honey production, and inhibit human wound pathogens. The aim of this pilot study was to investigate the e...
Kuroda T, Kinoshita Y, Niwa H, Shinzaki Y, Tamura N, Hobo S, Kuwano A.Meticillin-resistant Staphylococcus aureus (MRSA) infections have been confirmed in hospitalised Thoroughbred racehorses at the hospitals of two training centres in Japan since 2009. To investigate the source of infection, the authors examined the rate of nasal MRSA colonisation in 600 healthy Thoroughbred racehorses, 53 veterinarians and 16 office staff at the racehorse hospitals of the two training centres. MRSA was not isolated from healthy Thoroughbred racehorses or hospital office staff. However, MRSA was isolated from 16 veterinarians (30.1 per cent), and the colonisation rate was signif...
Carfora V, Caprioli A, Grossi I, Pepe M, Alba P, Lorenzetti S, Amoruso R, Sorbara L, Franco A, Battisti A.A Methicillin-resistantStaphylococcus aureus(MRSA) was isolated in Italy from a pathological sample of a mare presenting chronic purulent sinusitis and that had undergone frontal-sinus surgery three months before. Humans, horses, dogs and environmental samples were subsequently collected at the mare's stable and at the Veterinary Hospital, where the mare was operated/hospitalized, and screened for the presence of MRSA that was detected from other horses and from the environment at both sites. All the MRSA isolates belonged to clonal complex (CC)8, ST8-t11469-SCCmec-IVa, and showed similar phen...
Kováts N, Horváth E, Jancsek-Turóczi B, Hoffer A, Gelencsér A, Urbán P, Kiss ÍE, Bihari Z, Fekete C.Air quality in the stables is characterized by elevated level of dust and aeroallergens which are supposed to directly cause or exacerbate several respiratory disorders. The most often recognized problem is recurrent airway obstruction (RAO), previously known as chronic obstructive pulmonary disease (COPD). There is some indication that aeroallergens (among them endotoxins) may also cause inflammation in human airways and may exceed safe levels in stables. Monitoring studies have covered mainly the determination of the concentration of respirable particles and of culturable fungi and their tox...
Cuny C, Witte W.MRSA infections in equine clinics were reported from Northern America, Europe, Australia, and Japan. The majority of nosocomial infections in horses is obviously associated with particular MRSA clonal lineages. As already observed for epidemic MRSA in human hospitals more than 10 years ago, a dynamics of MRSA clonal lineages is also observed in European equine clinics: clonal lineages belonging to clonal complex (CC) 8 are on the retreat whereas MRSA attributed to CC398 become increasingly prevalent. The majority of CC398 isolates belong to a subpopulation which is particularly associated with...
Groves MD, Crouch B, Coombs GW, Jordan D, Pang S, Barton MD, Giffard P, Abraham S, Trott DJ.This work investigated the molecular epidemiology and antimicrobial resistance of methicillin-resistant Staphylococcus aureus (MRSA) isolated from veterinarians in Australia in 2009. The collection (n = 44) was subjected to extensive molecular typing (MLST, spa, SCCmec, dru, PFGE, virulence and antimicrobial resistance genotyping) and antimicrobial resistance phenotyping by disk diffusion. MRSA was isolated from Australian veterinarians representing various occupational emphases. The isolate collection was dominated by MRSA strains belonging to clonal complex (CC) 8 and multilocus sequence typ...
Toombs-Ruane LJ, Riley CB, Kendall AT, Hill KE, Benschop J, Rosanowski SM.To describe antimicrobial susceptibility, and identify antimicrobial resistance (AMR), in bacteria isolated from New Zealand foals. Methods: A database search was performed of submissions to a veterinary pathology laboratory between April 2004 and December 2013 for bacterial culture of samples from foals <3 weeks of age. Culture and susceptibility results were compiled with demographic information. Susceptibility results were as defined for the Kirby-Bauer disk diffusion susceptibility test based on Clinical Laboratory Standards Institute guidelines. Multi-drug resistance (MDR) was defined as ...
Petinaki E, Spiliopoulou I.Methicillin-resistant Staphylococcus aureus (MRSA) remains one of the most virulent human pathogens and has also recently been recognized as such in the veterinary settings. Companion animals, including dogs, cats, horses, small exotic animals, wildlife animals, and livestock, may constitute a reservoir for MRSA transmission to humans and vice versa. The evolution, emergence, and risk factors for MRSA transmission among colonized or infected animals are reviewed in the present paper, and infection control practices are discussed.
Kuroda T, Kinoshita Y, Niwa H, Mizobe F, Ueno T, Kuwano A, Hatazoe T, Hobo S.We report the first case of methicillin-resistant Staphylococcus aureus (MRSA) keratitis in a racehorse. A 5-year-old mare developed punctate keratitis after racing. The corneal ulcer continued to expand despite ophthalmic antimicrobial therapy. On day 6, a conjunctival graft surgery was performed. The mare was euthanized, following colitis and laminitis development on day 10. MRSA was isolated from the corneal swab taken at the time of euthanasia. Immunohistochemical analysis demonstrated gram-positive and anti-S. aureus monoclonal antibody-positive cocci infiltration of the corneal stroma; a...
Tirosh-Levy S, Steinman A, Carmeli Y, Klement E, Navon-Venezia S.Methicillin-resistant staphylococci (MRS), and specifically Methicillin-resistant Staphylococcus aureus (MRSA) colonization or infection have become a serious emerging condition in equine hospitals, with complex concerns regarding animals, personnel and public health. The objectives of this study were to evaluate the prevalence and risk factors for colonization by Staphylococci, MRS, and MRSA among horses in Israel. Nasal swabs were collected from horses at 17 riding stables (n=206), and from hospitalized horses admitted to a veterinary hospital (n=84). Species identification was performed by ...
Laverty G, McCloskey AP, Gorman SP, Gilmore BF.The threat of antimicrobial resistance has placed increasing emphasis on the development of innovative approaches to eradicate multidrug-resistant pathogens. Biofilm-forming microorganisms, for example, Staphylococcus epidermidis and Staphylococcus aureus, are responsible for increased incidence of biomaterial infection, extended hospital stays and patient morbidity and mortality. This paper highlights the potential of ultrashort tetra-peptide conjugated to hydrophobic cinnamic acid derivatives. These peptidomimetic molecules demonstrate selective and highly potent activity against resistant b...
Maddox TW, Clegg PD, Williams NJ, Pinchbeck GL.Antimicrobial resistance poses a significant threat to the continued successful use of antimicrobial agents for the treatment of bacterial infections. While the epidemiology of antimicrobial resistance in bacteria from man has been studied extensively, less work has been undertaken in companion animals, particularly horses. Methicillin-resistant Staphylococcus aureus has been identified as a cause of infections, with a low prevalence of nasal carriage by horses in the community but higher for hospitalised horses. Molecular characterisation has shown methicillin-resistant Staphylococcus aureus...
Walther B, Janssen T, Gehlen H, Vincze S, Borchers K, Wieler LH, Barton AK, Lübke-Becker A.With the rising importance of nosocomial infections in equine hospitals, increased efforts with regard to biosecurity and infection control are necessary. This even more since nosocomial infections are often associated with multi-drug resistant pathogens. Consequently, the implementation of targeted prevention programs is essential. Since nosocomial infections are usually multifactorial events, realization of only a single measure is rarely effective to overcome nosocomial spread in clinical practice. Equine patients may be colonized at admission with multi-drug resistant pathogens such as met...
Kinoshita Y, Niwa H, Katayama Y.Microbial substitution occasionally occurs following the administration of antimicrobials to horses that have pneumonia or pleuropneumonia. Four specific loop-mediated isothermal amplification (LAMP) assays were developed to detect some equine respiratory pathogens, namely strains of the Bacteroides-Prevotella group, Klebsiella pneumoniae, Stenotrophomonas maltophilia, and Staphylococcus aureus. These four LAMP assays and two previously published LAMP assays targeting Escherichia coli or Pseudomonas aeruginosa were used on clinical respiratory specimens and a high accordance found between the ...
Hidaka S, Kobayashi M, Ando K, Fujii Y.Lomefloxacin is a broad-spectrum fluoroquinolone antibiotic used for the treatment of bacterial extraocular disease. This study investigated the efficacy and safety of lomefloxacin eye drops for bacterial extraocular disease in horses. Lomefloxacin ophthalmic solution (0.3%) was instilled three times daily for 2-5 days in 65 horses diagnosed with bacterial extraocular disease based on clinical findings. Clinical observations and bacteriological examinations were performed at the start of treatment, 2 and 5 days after the start of treatment, and at the discontinuation or termination of treatmen...
Van den Eede A, Martens A, Floré K, Denis O, Gasthuys F, Haesebrouck F, Van den Abeele A, Hermans K.Equine methicillin-resistant Staphylococcus aureus (MRSA) carriage entails a risk of both equine and zoonotic transmission and infection. In Europe, CC398, the livestock-associated (LA-)MRSA is highly prevalent in horses and veterinary personnel at equine clinics. The extent of the MRSA reservoir created by healthy horses from the general population and associated health hazard for their daily caretakers is, however, unknown. This study aimed at screening healthy horse-caretaker couples from a broad range of home farms. At five equine gatherings, 166 couples were selected for MRSA screening in...
Whithair KJ, Bowersock TL, Blevins WE, Fessler JF, White MR, Van Sickle DC.Septic arthritis was induced in one antebrachiocarpal joint of seven horses by the intra-articular injection of 1 mL Staphylococcus aureus suspension containing a mean of 10(5) colony-forming units. Twenty-four hours after inoculation, four horses were treated by regional perfusion with 1 g of gentamicin sulfate, and three horses received 2.2 mg/kg gentamicin sulfate intravenously (IV) every 6 hours. Synovial fluid was collected for culture and cytology at regular intervals, and the synovial membranes were collected for culture and histologic examination at euthanasia 24 hours after the first ...
Gilbertie JM, Schaer TP, Engiles JB, Seiler GS, Deddens BL, Schubert AG, Jacob ME, Stefanovski D, Ruthel G, Hickok NJ, Stowe DM, Frink A, Schnabel LV.The leading cause of treatment failure in Staphylococcus aureus infections is the development of biofilms. Biofilms are highly tolerant to conventional antibiotics which were developed against planktonic cells. Consequently, there is a lack of antibiofilm agents in the antibiotic development pipeline. To address this problem, we developed a platelet-rich plasma (PRP)-derived biologic, termed BIO-PLY (for the BIOactive fraction of Platelet-rich plasma LYsate) which has potent in vitro bactericidal activity against S. aureus synovial fluid free-floating biofilm aggregates. Additional in vitro st...
López C, Carmona JU, Giraldo CE, Alvarez ME.1) To evaluate the bacteriostatic in vitro effect of pure platelet-rich plasma (P-PRP), pure platelet-rich gel (P-PRG), leukocyte-poor gel (LPG), platelet-poor plasma (PPP), and heat inactivated plasma (IP) against methicillin-sensitive Staphylococcus aureus (MSSA) over a period of 24 hours. 2) To determine the degradation of platelet factor-4 (PF-4), transforming growth factor beta 1 (TGF-β1), and platelet-derived growth factor isoform BB (PDGF-BB) in these equine blood components. 3) To establish correlations between platelet and leukocyte counts, PF-4 concentrations, and MSSA growth. Metho...
Adams R, Smith J, Locke S, Phillips E, Erol E, Carter C, Odoi A.Antimicrobial resistance limits traditional treatment options and increases costs. It is therefore important to estimate the magnitude of the problem so as to provide empirical data to guide control efforts. The aim of this study was to investigate the burden and patterns of antimicrobial resistance (AMR) among equine Staphylococcus samples submitted to the University of Kentucky Veterinary Diagnostic Laboratory (UKVDL) from 1993 to 2009. Retrospective data of 1711 equine Staphylococcus samples submitted to the UKVDL during the time period 1993 to 2009 were included in the study. Antimicrobial...
Van den Eede A, Hermans K, Van den Abeele A, Floré K, Dewulf J, Vanderhaeghen W, Némeghaire S, Butaye P, Gasthuys F, Haesebrouck F, Martens A.The increased incidence of methicillin-resistant Staphylococcus aureus (MRSA) infection in equine hospitals highlights the need for infection control protocols based on optimal patient screening. In horses, the deep ventral meatus of the nasal cavity is the principal site sampled to detect MRSA. However, in humans, the anterior nares are the preferred sampling site. The objective of this study was to determine the optimal sampling location in the nasal chambers for MRSA in horses by comparing the results obtained from three different locations (the vestibulum, diverticulum and ventral meatus) ...
Yasuda R, Kawano J, Matsuo E, Masuda T, Shimizu A, Anzai T, Hashikura S.The prevalence of staphylococci that harbor the mecA gene responsible for methicillin resistance was examined in healthy breeding mares. Staphylococci often cause diseases of horses such as metritis, keratitis, and abscess. Methicillin-resistant staphylococci would make antibiotic treatments ineffective, so it may be significant to know the distribution of mecA-harboring staphylococci in mares. Isolation of mecA-harboring staphylococci was achieved from nares and pasterns of 100 mares in Hokkaido, Japan. From 13% of the mares, mecA-harboring staphylococci, including 15 isolates of Staphylococc...
Devriese LA, Nzuambe D, Godard C.One hundred and twenty eight strains of Staphylococcus from lesions, mostly of the skin, in horses were identified and compared with 29 strains isolated from the healthy skin. The pathogenic species Staphylococcus aureus, S. intermedius and S. hyicus were found almost exclusively in lesions. Other species such as S. xylosus and S. sciuri were more frequently found on the healthy skin than in lesions. The S. aureus strains formed a very heterogeneous collection. Many of these strains were staphylokinase positive and rapidly coagulated bovine plasma. Such strains are rarely found in other animal...
Van den Eede A, Hermans K, Van den Abeele A, Floré K, Dewulf J, Vanderhaeghen W, Crombé F, Butaye P, Gasthuys F, Haesebrouck F, Martens A.Given the significance of methicillin-resistant Staphylococcus aureus (MRSA) infections for both horses and staff in equine veterinary hospitals, protocols are required to minimise the risk of nosocomial transmission, including the screening of the skin and nasal chambers of equine patients for evidence of infection. The objective of this study was to clarify the potential existence and extent of MRSA on the skin of horses requiring long-term hospitalisation (≥ 6 months). Thirty such horses were sampled at eight different locations on their skin and from their nasal chambers. MRSA was isolat...
Murphy RJT, Ramsay JP, Lee YT, Pang S, O'Dea MA, Pearson JC, Axon JE, Raby E, Abdulgader SM, Whitelaw A, Coombs GW.Staphylococcus aureus is a serious human and animal pathogen. Multilocus sequence type 612 (ST612) is the dominant methicillin-resistant S. aureus (MRSA) clone in certain South African hospitals and is sporadically isolated from horses and horse-associated veterinarians in Australia. Colonisation and infection by ST612-MRSA is increasing in Western Australia. Whole-genome sequencing was performed for 51 isolates of ST612-MRSA from Western Australian patients and healthcare workers, South African hospital patients, Australian veterinarians and New South Wales horses. Core genome phylogenies sug...
Tulamo RM, Bramlage LR, Gabel AA.Infectious arthritis was induced experimentally in one tarsocrural joint of six horses by intra-articular injection of 1 ml Staphylococcus-saline suspension containing 9 x 10(4) to 3 x 10(6) organisms. The corresponding contralateral joint was injected with 1 ml of saline and served as a control. The progression of the induced infectious arthritis was assessed over a nine-day period by clinical examination and sequential synovial fluid analysis with pH and lactate measurements. Changes in synovial fluid were present before clinical signs of infectious arthritis were manifested. The diagnostic ...
Pezzanite LM, Chow L, Phillips J, Griffenhagen GM, Moore AR, Schaer TP, Engiles JB, Werpy N, Gilbertie J, Schnabel LV, Antczak D, Miller D, Dow S....Rapid development of antibiotic resistance necessitates advancement of novel therapeutic strategies to treat infection. Mesenchymal stromal cells (MSC) possess antimicrobial and immunomodulatory properties, mediated through antimicrobial peptide secretion and recruitment of innate immune cells including neutrophils and monocytes. TLR-3 activation of human, canine and equine MSC has been shown to enhance bacterial killing and clearance in vitro, in rodent Staphylococcal biofilm infection models and dogs with spontaneous multi-drug-resistant infections. The objective of this study was to determi...
Tirosh-Levy S, Steinman A, Carmeli Y, Klement E, Navon-Venezia S.Methicillin-resistant staphylococci (MRS), and specifically Methicillin-resistant Staphylococcus aureus (MRSA) colonization or infection have become a serious emerging condition in equine hospitals, with complex concerns regarding animals, personnel and public health. The objectives of this study were to evaluate the prevalence and risk factors for colonization by Staphylococci, MRS, and MRSA among horses in Israel. Nasal swabs were collected from horses at 17 riding stables (n=206), and from hospitalized horses admitted to a veterinary hospital (n=84). Species identification was performed by ...
Bergström K, Nyman G, Widgren S, Johnston C, Grönlund-Andersson U, Ransjö U.The first outbreak of methicillin-resistant Staphylococcus aureus (MRSA) infection in horses in Sweden occurred in 2008 at the University Animal Hospital and highlighted the need for improved infection prevention and control. The present study describes interventions and infection prevention control in an equine hospital setting July 2008 - April 2010. Methods: This descriptive study of interventions is based on examination of policy documents, medical records, notes from meetings and cost estimates. MRSA cases were identified through clinical sampling and telephone enquiries about horses post...
Little SV, Hillhouse AE, Lawhon SD, Bryan LK.While Staphylococcus aureus is associated with significant morbidity and mortality in equids (horses, donkeys, and mules), few studies have performed whole-genome sequencing to fully categorize large collections of equine isolates. Such sequencing allows for a comprehensive analysis of the genetic lineage and relationships of isolates, as well as the virulence genes present in each, which can be important for understanding the epidemiology of strains and their range of infections. Seventy-two clinical Staphylococcus aureus isolates from equids were collected at the Texas A&M University Veterin...
Mallardo K, Nizza S, Fiorito F, Pagnini U, De Martino L.To investigate the prevalence of methicillin-resistant staphylococci (MRS) which is a potencial risk factor of transmission between animals and humans in different types of horses (harness racing-horses, breeding mares and riding-horses) and to compare the antimicrobial resistance of the isolates. Methods: A total of 191 healthy horses, housed at different locations of the Campania Region (Italy), were included in the study. Nasal swab samples were collected from each nostril of the horses. The mecA gene was detected by a nested PCR technique. Antibiotic susceptibility was tested for each isol...
Albert E, Biksi I, Német Z, Csuka E, Kelemen B, Morvay F, Bakos Z, Bodó G, Tóth B, Collaud A, Rossano A, Perreten V.Between July 2011 and May 2016, a total of 40 Staphylococcus aureus strains originating from 36 horses were confirmed as methicillin resistant (methicillin-resistant Staphylococcus aureus [MRSA]) in a university equine clinic. An additional 10 MRSA strains from 36 samples of clinic workers were obtained in October 2017. The first equine isolate represented the sequence type ST398, spa-type t011, and SCCmec IV. This isolate was resistant to a wide spectrum of antimicrobial agents. MRSA strains with the same genotype and with very similar resistance profiles were isolated on 21 more occasions fr...
Gómez-Sanz E, Simón C, Ortega C, Gómez P, Lozano C, Zarazaga M, Torres C.Eight coagulase-positive staphylococci from equines with different pathologies obtained between 2005 and 2011 were investigated. Isolates were characterized by different molecular techniques (spa-, agr-, MLST), and clonal relatedness of strains was investigated by ApaI and SmaI PFGE. Anti-microbial resistance and virulence profiles were determined. Six isolates were identified as Staphylococcus aureus, and two as Staphylococcus pseudintermedius. Of these, four isolates were methicillin-resistant S. aureus (MRSA) ST398 and one S. pseudintermedius was mecA positive and typed as ST68. One MRSA ...
Aktan I, Dunkel B, Cunningham FM.Activated platelets can contribute to host defense through release of products with bactericidal actions such as antimicrobial peptides and reactive oxygen species (ROS), as well as by forming heterotypic aggregates with neutrophils and enhancing their antimicrobial properties. Whilst release of vasoactive mediators from equine platelets in response to stimuli including bacterial lipopolysaccharide (LPS) has been documented, neither ROS production, nor the effects of activated platelets on equine neutrophil ROS production, have been reported. This study first sought evidence that activated equ...
Caddey B, Fisher S, Barkema HW, Nobrega DB.SUMMARYNumerous questions persist regarding the role of companion animals as potential reservoirs of antimicrobial-resistant organisms that can infect humans. While relative antimicrobial usage in companion animals is lower than that in humans, certain antimicrobial-resistant pathogens have comparable colonization rates in companion animals and their human counterparts, which inevitably raises questions regarding potential antimicrobial resistance (AMR) transmission. Furthermore, the close contact between pets and their owners, as well as pets, veterinary professionals, and the veterinary clin...
Sangiorgio DB, Hilty M, Kaiser-Thom S, Epper PG, Ramseyer AA, Overesch G, Gerber VM.Equine pastern dermatitis (EPD) is a common dermatological problem in horses, yet its aetiology and pathogenesis are poorly understood. Objective: This study aimed to investigate the effects of lesion severity and topical antimicrobial treatment on bacterial flora of EPD-affected skin. Methods: Sixteen horses with EPD were investigated. Methods: An observational study was conducted by assigning a clinical severity score ranging from 0 (macroscopically nonlesional) to 21 (severe), and sampling the most and least severely affected limbs of 16 horses (32 limbs) for bacteriological culture and 16S...
Hoquet F, Higgins R, Lessard P, Vrins A, Marcoux M.A total of 43 horses were used for the study of the pharyngeal bacterial flora. The median value of the number of bacteria in the group of 19 normal horses was 3.8 x 10(4) cfu/g of secretions. This value was 6.4 x 10(4)cfu/g in horses with grade I pharyngitis, 1.3 x 10(5) cfu/g in horses with grade II pharyngitis and 3.5 x 10(6) cfu/g in horses affected with grades III and IV pharyngitis. Corynebacterium spp, coagulase-negative staphylococci, Nocardia spp, Moraxella spp and Enterobacter spp were the most frequently encountered bacteria in the normal animals as well as in horses affected with p...
Van den Eede A, Martens A, Feryn I, Vanderhaeghen W, Lipinska U, Gasthuys F, Butaye P, Haesebrouck F, Hermans K.In Europe, methicillin-resistant Staphylococcus aureus (MRSA) belonging to the clonal complex (CC) 398 has become an important pathogen in horses, circulating in equine clinics and causing both colonization and infection. Whether equine MRSA is bound to hospitals or can also circulate in the general horse population is currently unknown. This study, therefore, reports the nasal and perianal MRSA screening of 189 horses on 10 farms in a suspected high prevalence region (East- and West-Flanders, Belgium). Results: Only one horse (0.53%) from one farm (10%) tested positive in the nose. It carried...
Carfora V, Caprioli A, Grossi I, Pepe M, Alba P, Lorenzetti S, Amoruso R, Sorbara L, Franco A, Battisti A.A Methicillin-resistantStaphylococcus aureus(MRSA) was isolated in Italy from a pathological sample of a mare presenting chronic purulent sinusitis and that had undergone frontal-sinus surgery three months before. Humans, horses, dogs and environmental samples were subsequently collected at the mare's stable and at the Veterinary Hospital, where the mare was operated/hospitalized, and screened for the presence of MRSA that was detected from other horses and from the environment at both sites. All the MRSA isolates belonged to clonal complex (CC)8, ST8-t11469-SCCmec-IVa, and showed similar phen...
Othman AA, Hiblu MA, Abbassi MS, Abouzeed YM, Ahmed MO.The present study investigated the colonization rates and antimicrobial susceptibility of Staphylococcus species isolated from the nostrils of healthy horses. A nonselective laboratory approach was applied, followed by confirmation using a Phoenix automated microbiological system. Among the 92 horses included in the study, 48.9% (45/92) carried Staphylococcus species of mostly the coagulase-negative staphylococci (CoNS) type yielding 70 Staphylococcus strains. Of these strains, 37.1% (26/70; 24 CoNS and 2 coagulase-positive staphylococci; CoPS) were identified as methicillin-resistant staphylo...
López C, Alvarez ME, Carmona JU.The aims were (1) to evaluate the bacteriostatic effect of platelet-rich plasma (PRP), platelet-rich gel (PRG), leukocyte-poor plasma (LPP), leukocyte-poor gel (LPG), plasma, and heat-inactivated plasma (IP) on both methicillin-sensitive Staphylococcus aureus (MSSA) and methicillin-resistant Staphylococcus aureus (MRSA) over a period of 24 h; (2) to determine and to compare the concentrations and degradation over time of platelet factor 4 (PF-4), transforming growth factor beta 1 (TGF-β 1), and platelet-derived growth factor isoform BB (PDGF-BB); and (3) to identify any correlations between...
Fungwithaya P, Boonchuay K, Narinthorn R, Sontigun N, Sansamur C, Petcharat Y, Thomrongsuwannakij T, Wongtawan T.Staphylococci are commensal bacteria and opportunistic pathogens found on the skin and mucosa. Sports animals are more prone to injury and illness, and we believe that antimicrobial agents might be extensively used for the treatment and cause the existence of antimicrobial-resistant (AMR) bacteria. This study aimed to investigate the diversity and AMR profile of staphylococci in sports animals (riding horses, fighting bulls, and fighting cocks) in South Thailand. Unassigned: Nasal (57 fighting bulls and 33 riding horses) and skin swabs (32 fighting cocks) were taken from 122 animals. Staphyloc...
Bergström K, Bengtsson B, Nyman A, Grönlund Andersson U.An outbreak of methicillin-resistant Staphylococcus aureus (MRSA) infections in horses in Sweden raised questions concerning the risk posed by horses to their surroundings following MRSA infections. This initiated a longitudinal study to investigate how long MRSA-infected horses remained positive and to test the sensitivity of different anatomical sampling sites for detection of MRSA. Between October 2008 and June 2010, 9 of 15 horses notified as having MRSA-infected wounds fitted the case criteria for the study. The cases were sampled at five anatomical sites (nostrils, corner of mouth, paste...
