The National Centre for Zoonosis Research ~ Antimicrobial use and carriage of antimicrobial-resistant Escherichia coli and staphylococci in dogs and horses in the community: molecular mechanisms of resistance and risk to humans.

Antimicrobial use and carriage of antimicrobial-resistant Escherichia coli and staphylococci in dogs and horses in the community: molecular mechanisms of resistance and risk to humans.

Dog and child Humans have frequent contact with companion animals. The effect of pet ownership on human health has been studied and pets provide companionship and also probably confer physiological and psychological health benefits. However, a potential risk from pet ownership is the acquisition of zoonotic disease. Approximately 30 to 40 pathogens that are zoonotic are present in companion animals (Greene and Levy 2006).

Antimicrobial use in companion animals

Antimicrobial products are used in the treatment of many infectious conditions in companion animals and their use is important in maintaining animal health and welfare. However, increasingly bacteria are developing resistance to treatment with antimicrobial products and this has led to problems in the treatment of some infections in animals. In addition, this may have an impact on treatment of human infections by transfer of either antimicrobial resistant organisms from animals to people or via transfer of resistance genes between bacteria. Clearly we need to maintain the effectiveness of antimicrobials for use in animals and humans.

As part of this and in line with the strategy that DEFRA have produced for control in food-producing animals (Strategy for Developing and Implementing a Programme of Surveillance for Antimicrobial Resistance in Animals in England and Wales, DEFRA), surveillance of antimicrobial resistance in companion animals is important. Alongside this, further information on the use of antimicrobials in dogs and horses would ultimately lead to risk analysis and so the development of improved guidelines for their usage in such species.

collaborators

Professor Tom Humphreys (University of Bristol)
Professor Martin Woodward (Veterinary Laboratories Agency, Weybridge)
Professor Chris Teale (Veterinary Laboratories Agency, Weybridge)
Miss Jane Heller (University of Glasgow)

Antibiotic Resistance in Companion animals: Dogs and Horses

The whole project is DEFRA funded, with the equine component co-funded by the equine charity Bransby Home of Rest for Horses. This part of the work will comprise two main studies:-

· Nationwide cross-sectional survey: antimicrobial resistant E. coli and staphylococci will be collected by faecal samples and nasal swabs from dogs and horses attended by veterinary surgeons throughout the United Kingdom mainland. Demographic data and information on previous antimicrobial treatment and exposure will be collected to allow investigation of the epidemiology of antimicrobial resistance in the community.

Antimicrobial susceptibility testing of E. coli

Antimicrobial susceptibility testing of E. coli

· Cohort study at the Philip Leverhulme Equine Hospital: horses undergoing treatment with antimicrobials and untreated horses will be followed to investigate the development and acquisition of nosocomial antimicrobial resistance. In particular, this hospital-based study will identify significant risk factors associated with acquisition and propagation of antimicrobial drug resistance in horses in a hospital environment.

Samples obtained from these studies will be cultured and subjected to a range of analytical techniques including antibiotic susceptibility testing, polymerase chain reaction (PCR) for resistance genes and gene typing to allow identification of specific strain types.

· A nationwide cross-sectional survey on antimicrobial usage in veterinary practices: the aims of this study are to gather data on antimicrobial use from a cross-section of companion animal practices including rural and urban communities across the UK

· Microbial Risk Assessment: A key component of successful risk assessment is collaboration at all stages, and this will hence be carried out via regular consultation between risk assessor and scientists involved in all aspects of the project. A generic framework, identifying all possible exposure routes between companion animal to human, will first be created.

Thus the project will lead to a greater understanding of the role of antimicrobial treatment in companion animals in the overall epidemiology of antimicrobial resistance in animals and enable stakeholders to make informed judgements regarding future antimicrobial use.

In addition the results will inform the veterinary profession to improve antimicrobial usage within companion animal practice and ultimately lead to improvements in treatments of dogs and horses and thus animal welfare.

An improved rationale for antimicrobial prescribing in companion animals could reduce antimicrobial resistance and transfer of such resistance to man and therefore contribute positively towards public health.