Toxigenic Corynebacterium ulcerans associated with upper respiratory infections in cats and dogs.

OBJECTIVES: To describe infection in companion animals with the zoonotic pathogen Corynebacterium ulcerans and to determine its prevalence in clinically-affected and healthy animals. MATERIALS AND METHODS: The clinical presentation and treatment of three cases of C. ulcerans infection is described. Two studies to determine C. ulcerans prevalence rates were undertaken: (a) a prospective study of nasal samples from healthy animals, 479 dogs and 72 cats; (b) a retrospective analysis of records of nasal samples collected over a 10-year period from 189 dogs and 64 cats affected by respiratory signs. RESULTS: Toxigenic C. ulcerans was isolated from four cats with nasal discharge while concurrent C. ulcerans and mecC methicillin-resistant S. aureus infection was detected in a dog suffering from chronic nasal discharge. Clinical features were not distinctive and all cases recovered following antimicrobial treatment. Multilocus sequence typing supported a common source for isolates from the shelter cats. Carriage rates of C. ulcerans in healthy animals were 0.42% (2/479) in dogs and 0.00% (0/72) in cats whereas in animals with signs of upper respiratory tract infection prevalence rates were 0.53% (1/189) in dogs and 6.25% (4/64) in cats. CLINICAL SIGNIFICANCE: Clinicians should be aware that dogs and cats can be infected with (or carriers of) toxigenic C. ulcerans Considering the potential zoonotic risk, assistance from medical and public health colleagues should be sought in confirmed cases.

Investigation of the persistence and transmission of MRSA CC 5 in pigs following intra-nasal inoculation.

MRSA CC5 spa type t002 appears to have a broad host range, has been isolated from animals and in-contact humans in Ireland and could potentially become established in pigs in Ireland. The aims of this study were to determine if MRSA CC5 spa type t002 could persist in the tissues of the porcine upper respiratory tract following intra-nasal inoculation; to determine the relative importance of environmental and animal sources of the bacterium in the transmission cycle and to determine the importance of the pharynx as a carriage site of Staphylococcus aureus and MRSA. Twelve pigs were inoculated intra-nasally with MRSA CC5 t002. After 1 or 6 days, the inoculated pigs were removed from the contaminated environment, were washed in an antiseptic solution and placed in a clean house with a group of naive pigs (in-contact group). Another group of naive pigs was placed in the contaminated environment to assess transmission from the environment (environmental group). Nasal swabs, environmental swabs and tissue samples from the upper respiratory tract were taken for MRSA culture. Infection rates were calculated for each group of exposed pigs. MRSA persisted in the pharyngeal tissues of 6 inoculated pigs for at least 30 days and higher counts of S. aureus were found in pharyngeal tissues than in other sites. In this study we were able to demonstrate the establishment of colonisation by MRSA CC5 spa type t002 in commercially sourced pigs already colonised by S. aureus; however, colonisation was sporadic despite the inoculation of large doses. Onward transmission via pig-to-pig contact or environmental contamination was possible and a significant difference was found between the proportion of pigs infected in the environmental group and the proportion infected in the in-contact group during the first 5 days. However, no significant difference was detected in overall infection rates between the 2 groups. The tissues of the pharynx were found to carry greater numbers of S. aureus than other tissues of the upper respiratory tract; therefore, pharyngeal carriage of MRSA and S. aureus in pigs may be more significant than previously thought.

Isolation rates of meticillin-resistant Staphylococcus aureus in dogs, cats and horses in Ireland.

A retrospective analysis and prospective surveillance study were conducted to determine isolation rates of meticillin-resistant Staphylococcus aureus (MRSA) in dogs, cats and horses in Ireland. Clinical samples that had been submitted to University College Dublin (UCD) for routine microbiological examination over a four-year period (2003 to 2006) were analysed in the retrospective analysis, which included clinical samples from 3866 animals. In the prospective surveillance study, samples from healthy animals presenting for elective surgery as well as from animals with a clinical presentation suggestive of MRSA infection were investigated. Animals attending 30 veterinary practices throughout Ireland and a similar population of animals presented to UCD were studied. The isolation rates for animals in the retrospective study were 1.1 per cent (32 of 2864) for dogs, 0.7 per cent (four of 619) for cats and 5.2 per cent (20 of 383) for horses. The overall isolation rate of MRSA was 1.4 per cent (56 of 3866). Isolation rates for healthy animals in the prospective study were 0.4 per cent (one of 286) for dogs and 1.7 per cent (four of 236) for horses; MRSA was not isolated from cats (0 of 47). Isolation rates for animals suspected of being infected with MRSA were 8.1 per cent (14 of 173) for dogs and 4.6 per cent (three of 65) for horses; MRSA was not isolated from cats (0 of 47).

Detection of three distinct genetic lineages in methicillin-resistant Staphylococcus aureus (MRSA) isolates from animals and veterinary personnel.

This study involved the phenotypic and molecular characterization of a population of methicillin-resistant Staphylococcus aureus isolates from animals and from veterinary personnel in Ireland. Isolates from 77 animals (dogs, n=44; cats, n=4; horses, n=29) and from 28 veterinary personnel were characterized using their antimicrobial resistance profiles and pulsed-field gel electrophoresis patterns. In addition, a representative number of these isolates (n=52) were further analysed using spa-typing techniques. The results obtained identified the presence of three distinct clonal complexes, CC5, CC8 and CC22, in both animal and human isolates. Two of these clonal complexes, CC8 and CC22, respectively, have been previously described in animals in Ireland but the presence of the third complex CC5 is a novel finding. The significance of this development, in relation to human and animal healthcare, is discussed.

Zoonotic transmission of Streptococcus equi subsp. zooepidemicus from a dog to a handler.

This is, to the best of our knowledge, the first case report to describe the apparent transmission of Streptococcus equi subsp. zooepidemicus from an infected dog to a handler who subsequently developed severe systemic infection. Characterization of the haemolytic streptococci isolated from both the patient and the dog, by phenotypic and molecular analysis, confirmed the canine and human isolates were identical.

High-level gentamicin-resistant and vancomycin-resistant Enterococcus faecium isolated from a wound in a dog.

This report describes the first clinical case, in Europe, of a high-level gentamicin-resistant and vancomycin-resistant Enterococcus faecium infection in a dog. The aim of this report is to alert the veterinary profession to high-level gentamicin-resistant and vancomycin-resistant Enterococcus faecium in companion animal patients. Multi-drug resistant strains of this pathogen are the cause of considerable problems in human hospitals and for community healthcare professionals worldwide. The potential for a similar impact within veterinary medicine is discussed.

Methicillin-resistant Staphylococcus aureus isolated from a veterinary surgeon and five dogs in one practice.

Methicillin-resistant Staphylococcus aureus (MRSA) was isolated from five dogs with wound discharges after surgical procedures at a veterinary practice, and MRSA with similar molecular and phenotypic characteristics was isolated from the nares of one veterinary surgeon in the practice. The pulsed-field gel electrophoresis patterns of all the isolates were indistinguishable from each other and from the most common human isolates of MRSA in Ireland.

Methicillin-resistant Staphylococcus aureus (MRSA) isolated from animals and veterinary personnel in Ireland.

Reports of methicillin-resistant Staphylococcus aureus (MRSA) in animals have become more frequent in recent years. This paper documents the recovery of MRSA from animals with respiratory, urinary tract or wound infection and from animals subjected to surgical procedures following treatment in one veterinary hospital and 16 private veterinary clinics in different geographical locations throughout Ireland. MRSA was recovered from 25 animals comprising 14 dogs, eight horses, one cat, one rabbit and a seal, and also from 10 attendant veterinary personnel. Clinical susceptibility testing suggested that the 35 isolates fell into two different groups. One group of isolates (Group 1) was resistant to one or more of the following classes of antimicrobials: macrolides, lincosamines, tetracyclines and/or fluoroquinolones. The second group (Group 2) was resistant to macrolides, aminoglycosides, tetracyclines and trimethoprim/sulphamethoxazole and variably resistant to fluoroquinolones, lincosamines and rifampicin. One isolate in Group 2 was susceptible to trimethoprim. Epidemiological typing by antibiogram-resistogram (AR) typing, biotyping and by chromosomal DNA restriction fragment length polymorphism analysis using SmaI digestion followed by pulsed field gel electrophoresis (PFGE), confirmed these two major clusters. PFGE analysis showed that most isolates from non-equine animals were indistinguishable from each other and from the isolates from personnel caring for these animals. MRSA was isolated from eight horses which attended six different veterinary practices before referral to an equine veterinary hospital. Isolates from the eight horses and from their attendant personnel had PFGE patterns that were indistinguishable and were unlike the patterns obtained from the other isolates. Comparison of PFGE patterns of isolates from veterinary sources with patterns from MRSA recovered in human hospitals showed that the most frequently occurring pattern of MRSA from non-equine animals was indistinguishable from the predominant pattern obtained from the most prevalent MRSA strain in the human population in Ireland. However, the patterns of the isolates from horses were unlike any patterns previously reported in Irish studies of human isolates. This study shows that transmission of two strains of MRSA is occurring in veterinary practices in Ireland and that one strain may have arisen from human hospitals. The source of the second strain remains to be determined.