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1.
beta-Lactams are among the most clinically important antimicrobials in both human and veterinary medicine. Bacterial resistance to beta-lactams has been increasingly observed in bacteria, including those of animal origin. The mechanisms of beta-lactam resistance include inaccessibility of the drugs to their target, target alterations and/or inactivation of the drugs by beta-lactamases. The latter contributes predominantly to beta-lactam resistance in Gram-negative bacteria. A variety of beta-lactamases have been identified in bacteria derived from food-producing and companion animals and may further serve as a reservoir for beta-lactamase-producing bacteria in humans. While this review mainly describes beta-lactamases from animal-derived Escherichia coli and Salmonella spp., beta-lactamases from animal-derived Campylobacter spp., Enterococcus spp., Staphylococcus spp. and other pathogens are also discussed. Of particular concern are the increasingly-isolated plasmid-encoded AmpC-type CMY and extended-spectrum CTX-M beta-lactamases, which mediate acquired resistance to extended-spectrum beta-lactams. The genes encoding these enzymes often coexist with other antimicrobial resistance determinants and can also be associated with transposons/integrons, increasing the potential enrichment of multidrug resistant bacteria by multiple antimicrobial agents as well as dissemination of the resistance determinants among bacterial species. Characterization of beta-lactam-resistant animal-derived bacteria warrants further investigation of the type and distribution of beta-lactamases in bacteria of animal origin and their potential impact on human medicine.  相似文献   

2.
The application of antimicrobial agents has proved to be the main risk factor for development, selection and spread of antimicrobial resistance. This link applies to the use of antimicrobial agents in human and in veterinary medicine. Furthermore, antimicrobial-resistant bacteria and resistant genes can be transmitted from animals to humans either by direct contact or via the food chain. In this context, risk management has to be discussed regarding prevention and control of the already existing antimicrobial resistance. One of the primary risk management measures in order to control the development and spread of antimicrobial resistances is by regulating the use of antimicrobial agents and subjecting their use to guidelines. Thereby, the occurrence of antimicrobial resistant bacteria in the human and veterinary habitat can be controlled to a certain degree. There is little information about past attempts to prevent the development of resistances or to control them, and even less is known about the effectiveness or the cost intensiveness of such efforts. Most of the strategies focus on preventing and controlling antimicrobial resistance by means of the reduction or limitation of the use of antimicrobial agents in food-producing animals.  相似文献   

3.
The total quantity of use in companion animals is generally believed to be relatively small in comparison with antimicrobial use in food animals. Use in companion animals is principally for treatment, whereas the greater proportion of use in food animals is for prophylaxis, metaphylaxis and growth promotion. Therefore, it is important to collect data on end use in companion animals so that overall estimates of use in companion animals can be generated and separated from estimates for food animals. However, data from antimicrobial use in companion animals are extremely limited and no serious attempts to collect such data have ever been made in the United States. The lack of usage data in is concomitant with the dearth of information on antimicrobial resistance in companion animals. Companion animals have been involved in the transmission to humans of, or become infected with, foodborne zoonotic bacteria such as Salmonella and Campylobacter. Companion animals are an integral part of the ecology of antimicrobial resistance through their contact with food animals and exposure to antimicrobials for disease treatment and through contact with humans and the environment. In the practice of companion animal medicine, antimicrobial use data are important for understanding the potential impact on companion animal heath posed by antimicrobial resistance transferred from food animals, humans and the environment, and the threat to humans and other companion animals posed by antimicrobial use in companion animals. Basic information on the patterns and quantities of antimicrobial use in combination with resistance surveillance data, could help companion animal veterinarians understand the potential for development, or evidence of, an antimicrobial resistance problem in their practices, the role of companion animals in the overall epidemiology of antimicrobial resistance, and for comparison with local, regional, or national data. The combination of data from either a sentinel site system of clinics or a use survey with national data from the pharmaceutical industry should provide sufficient data to credibly estimate the total volume and patterns of antimicrobial use in companion animal medicine. The time and effort for use monitoring or to complete a survey would likely become burdensome. Practice management software now utilized at most companion animal clinics could be used to generate antimicrobial use data as well as patient population data as surrogate for the true population at risk for patient encounters in a companion animal practice.  相似文献   

4.
Besides their role as commensals on the skin and mucosal surfaces, staphylococci may be involved in a wide variety of diseases in animals. Staphylococcal infections in animals are mainly treated with antimicrobial agents and as a consequence, staphylococci from animal sources have developed and/or acquired resistance to the respective antimicrobial agents. Resistance statistics obtained from national monitoring programmes on staphylococci from cattle and pigs, but also from surveillance studies on staphylococci involved in diseases in dogs are reported and reviewed with regard to their comparability. This review mainly focusses on the genetic basis of antimicrobial resistance in staphylococci of animal origin. Particular attention is paid to resistance to those antimicrobial agents which are most frequently used in veterinary medicine, but also to antimicrobial agents, such as chloramphenicol and mupirocin, which are used in specific cases for the control of staphylococcal infections in pets and companion animals. In addition, plasmids and transposons associated with the respective resistance properties and their ways of spreading between members of the same or different staphylococcal species, but also between staphylococci and other gram-positive bacteria, are described.  相似文献   

5.
The vast literature on antimicrobial drug use in animals has expanded considerably recently as the antimicrobial resistance (AMR) crisis in human medicine leads to questions about all usage of antimicrobial drugs, including long-term usage in intensively managed food animals for growth promotion and disease prevention. Attention is also increasingly focusing on antimicrobial use and on bacterial resistance in companion animals, which are in intimate contact with the human population. They may share resistant bacteria with their owners, amplify resistant bacteria acquired from their owners, and act as a reservoir for human infection. Considerable effort is being made to describe the basis of AMR in bacterial pathogens of animals. Documentation of many aspects of use of antimicrobials in animals is, however, generally less developed and only a few countries can describe quantities of drugs used in animals to kg levels annually. In recent years, many national veterinary associations have produced 'prudent use guidelines' to try to improve antimicrobial drug use and decrease resistance, but the impact of guidelines is unknown. Within the evolving global movement for 'antimicrobial stewardship', there is considerable scope to improve many aspects of antimicrobial use in animals, including infection control and reduction of use, with a view to reducing resistance and its spread, and to preserving antimicrobial drugs for the future.  相似文献   

6.
Development of antimicrobial resistance is an inevitable consequence of exposure of microorganisms to antimicrobial agents. Although emergence of resistance cannot be prevented, it can be retarded by minimizing use of antimicrobial agents and avoiding selection of relatively resistant pathogenic and nonpathogenic strains caused by exposure to tissue concentrations that confer a competitive advantage. Most attention in veterinary medicine has focused on the emergence of resistance in food-borne pathogens, with relatively little attention being devoted to small companion animals, despite the frequent use of antimicrobial agents in these animals, evidence that resistance is emerging, and potential for transfer of resistance between companion animals and people. To retard further emergence of resistance in small companion animals, it is imperative that surveillance programs be instituted to monitor development of resistance.  相似文献   

7.
Antimicrobial‐resistant bacteria represent an important concern impacting both veterinary medicine and public health. The rising prevalence of extended‐spectrum beta‐lactamase (ESBL), AmpC beta‐lactamase, carbapenemase (CRE) and fluoroquinolone‐resistant Enterobacteriaceae continually decreases the efficiency of clinically important antibiotics. Moreover, the potential for zoonotic transmission of antibiotic‐resistant enteric bacteria increases the risk to public health. Our objective was to estimate the prevalence of specific antibiotic‐resistant bacteria on human contact surfaces in various animal environments. Environmental surface samples were collected from companion animal shelters, private equine facilities, dairy farms, livestock auction markets and livestock areas of county fairs using electrostatic cloths. Samples were screened for Enterobacteriaceae expressing AmpC, ESBL, CRE or fluoroquinolone resistance using selective media. Livestock auction markets and county fairs had higher levels of bacteria expressing both cephalosporin and fluoroquinolone resistance than did equine, dairy, and companion animal environments. Equine facilities harboured more bacteria expressing cephalosporin resistance than companion animal shelters, but less fluoroquinolone resistance. The regular use of extended‐spectrum cephalosporins in livestock populations could account for the increased levels of cephalosporin resistance in livestock environments compared to companion animal and equine facilities. Human surfaces, as well as shared human and animal surfaces, were contaminated with resistant bacteria regardless of species environment. Detecting these bacteria on common human contact surfaces suggests that the environment can serve as a reservoir for the zoonotic transmission of antibiotic‐resistant bacteria and resistance genes. Identifying interventions to lower the prevalence of antibiotic‐resistant bacteria in animal environments will protect both animal and public health.  相似文献   

8.
Antimicrobial drug use in veterinary medicine   总被引：1，自引：0，他引：1  
Recognizing the importance of antimicrobial resistance and the need for veterinarians to aid in efforts for maintaining the usefulness of antimicrobial drugs in animals and humans, the Board of Regents of the American College of Veterinary Internal Medicine charged a special committee with responsibility for drafting this position statement regarding antimicrobial drug use in veterinary medicine. The Committee believes that veterinarians are obligated to balance the well-being of animals under their care with the protection of other animals and public health. Therefore, if an animal's medical condition can be reasonably expected to improve as a result of treatment with antimicrobial drugs, and the animal is under a veterinarian's care with an appropriate veterinarian-client-patient relationship, veterinarians have an obligation to offer antimicrobial treatment as a therapeutic option. Veterinarians also have an obligation to actively promote disease prevention efforts, to treat as conservatively as possible, and to explain the potential consequences associated with antimicrobial treatment to animal owners and managers, including the possibility of promoting selection of resistant bacteria. However, the consequences of losing usefulness of an antimicrobial drug that is used as a last resort in humans or animals with resistant bacterial infections might be unacceptable from a public or population health perspective. Veterinarians could therefore face the difficult choice of treating animals with a drug that is less likely to be successful, possibly resulting in prolonged or exacerbated morbidity, to protect the good of society. The Committee recommends that voluntary actions be taken by the veterinary profession to promote conservative use of antimicrobial drugs to minimize the potential adverse effects on animal or human health. The veterinary profession must work to educate all veterinarians about issues related to conservative antimicrobial drug use and antimicrobial resistance so that each individual is better able to balance ethical obligations regarding the perceived benefit to their patients versus the perceived risk to public health. Specific means by which the veterinary profession can promote stewardship of this valuable resource are presented and discussed in this document.  相似文献   

9.
Quinolone resistance in Escherichia coli.   总被引：3，自引：0，他引：3  
Escherichia coli is an important pathogen of animals and humans that causes great financial cost in food production by causing disease in food animals. The quinolones are a class of synthetic antimicrobial agents with excellent activity against Escherichia coli and other Gram-negative bacteria used in human and veterinary medicine. Different quinolones are used to treat various conditions in animals in different parts of the world. All members of this class of drug have the same mode of action: inhibition of topoisomerase enzymes, DNA Gyrase and Topoisomerase IV. Escherichia coli can become resistant to quinolones by altering the target enzymes, reducing permeability of the cell to inhibit their entry, or by actively pumping the drug out of the cell. All these resistance mechanisms can play a role in high-level fluoroquinolone resistance, however target site mutations appear to be most important. As all quinolones act in the same way resistance to one member of the class will also confer decreased susceptibility to all members of the family. Quinolone resistant Escherichia coli in animals have increased in numbers after quinolone introduction in a number of different case studies. The resistance mechanisms in these isolates are the same as those in resistant strains found in humans. Care needs to be taken to ensure that quinolones are used sparingly and appropriately as highly resistant strains of Escherichia coli can be selected and may pass into the food chain. As these drugs are of major therapeutic importance in human medicine, this is a public health concern. More information as to the numbers of quinolone resistant Escherichia coli and the relationship between resistance and quinolone use is needed to allow us to make better informed decisions about when and when not to use quinolones in the treatment of animals.  相似文献   

10.
Quinolone resistance is studied and reported increasingly in isolates from humans, food-producing animals and companion animals. Resistance can be caused by chromosomal mutations in topoisomerase genes, plasmid-mediated resistance genes, and active transport through efflux pumps. Cross sectional data on quinolone resistance mechanisms in non-pathogenic bacteria from healthy veal calves is limited. The purpose of this study was to determine the prevalence and characteristics of quinolone resistance mechanisms in Escherichia coli isolates from veal calves, after more than 20 years of quinolone usage in veal calves. MIC values were determined for all isolates collected as part of a national surveillance program on antimicrobial resistance in commensal bacteria in food-producing animals in The Netherlands. From the strains collected from veal calves in 2007 (n=175) all isolates with ciprofloxacin MIC ≥ 0.125 mg/L (n=25) were selected for this study, and screened for the presence of known quinolone resistance determinants. In this selection only chromosomal mutations in the topoisomerase type II and IV genes were detected. The number of mutations found per isolate correlated with an increasing ciprofloxacin MIC. No plasmid-mediated quinolone resistance genes were found. The contribution of efflux pumps varied from no contribution to a 16-fold increase in susceptibility. No correlation was found with the presence of resistance genes of other antimicrobial classes, even though all quinolone non-wild type isolates were resistant to 3 or more classes of antibiotics other than quinolones. Over twenty years of quinolone usage in veal calves in The Netherlands did not result in a widespread occurrence of plasmid-mediated quinolone resistance, limiting the transmission of quinolone resistance to clonal distribution.  相似文献   

11.
Objective: To review the human and companion animal veterinary literature on nosocomial infections and antimicrobial drug resistance as they pertain to the critically ill patient. Data sources: Data from human and veterinary sources were reviewed using PubMed and CAB. Human data synthesis: There is a large amount of published data on nosocomially‐acquired bloodstream infections, pneumonia, urinary tract infections and surgical site infections, and strategies to minimize the frequency of these infections, in human medicine. Nosocomial infections caused by multi‐drug‐resistant (MDR) pathogens are a leading cause of increased patient morbidity and mortality, medical treatment costs, and prolonged hospital stay. Epidemiology and risk factor analyses have shown that the major risk factor for the development of antimicrobial resistance in critically ill human patients is heavy antibiotic usage. Veterinary data synthesis: There is a paucity of information on the development of antimicrobial drug resistance and nosocomially‐acquired infections in critically ill small animal veterinary patients. Mechanisms of antimicrobial drug resistance are universal, although the selection effects created by antibiotic usage may be less significant in veterinary patients. Future studies on the development of antimicrobial drug resistance in critically ill animals may benefit from research that has been conducted in humans. Conclusions: Antimicrobial use in critically ill patients selects for antimicrobial drug resistance and MDR nosocomial pathogens. The choice of antimicrobials should be prudent and based on regular surveillance studies and accurate microbiological diagnostics. Antimicrobial drug resistance is becoming an increasing problem in veterinary medicine, particularly in the critical care setting, and institution‐specific strategies should be developed to prevent the emergence of MDR infections. The collation of data from tertiary‐care veterinary hospitals may identify trends in antimicrobial drug resistance patterns in nosocomial pathogens and aid in formulating guidelines for antimicrobial use.  相似文献   

12.
Reasons for performing study: The increasing prevalence of antimicrobial resistant bacteria such as antimicrobial‐resistant and extended spectrum β‐lactamase (ESBL)‐producing Escherichia coli represents a significant problem for human and veterinary medicine. Despite this, the risk factors for faecal carriage of such bacteria by horses in the UK, particularly those in the wider community, have not been well described. Objectives: To characterise the risk factors for faecal carriage of antimicrobial‐resistant E. coli amongst horses in the mainland UK. Methods: A cross‐sectional study of horses recruited by 65 randomly selected equine veterinary practices was conducted, with a faecal sample collected and self‐administered questionnaire completed by the horse owner. Faecal samples were cultured for antimicrobial‐resistant E. coli, with isolates confirmed as E. coli having their antimicrobial resistance profile determined. Multilevel, multivariable logistic regression models were used to investigate risk factors for the carriage of antimicrobial‐resistant E. coli in the sample population. Results: Faecal samples and completed questionnaires were obtained for 627 horses located on 475 premises. Recent hospitalisation, contact with specific types of nonequid animals, the type of premises, the surrounding land use, the reason for veterinary treatment received in the last 6 months and antimicrobial treatment in the previous 10 days were identified as risk factors for many of the antimicrobial‐resistance outcomes considered. Being stabled on the same yard as a recently hospitalised horse was identified as a risk factor for increased risk of carriage of ESBL‐producing E. coli. Conclusions and potential relevance: Increasing antimicrobial resistance may have significant health implications for the horse population of Great Britain. This form of epidemiological investigation highlights potential risk factors that may be controlled to limit the extent of the problem.  相似文献   

13.
美国兽用抗菌药耐药性管理   总被引：1，自引：1，他引：0  
全面介绍了美国兽用抗菌药耐药性的管理机构和管理措施,希望为我国兽药耐药性相关政策的制定和措施的实行提供一定的依据和参考。  相似文献   

14.
Fifteen years (1984-1998) of records from a Veterinary Teaching Hospital were analyzed to determine whether antimicrobial drug resistance in coagulase-positive Staphylococcus spp. (S. aureus, S. intermedius) isolated from clinical infections in dogs has increased, and whether there has been a change in the species of bacteria isolated from urinary tract infections in dogs. In coagulase-positive Staphylococcus spp., a complex pattern showing both increases and decreases of resistance to different classes of antimicrobial drugs was observed, reflecting the changing use of different antimicrobial drug classes in the hospital over a similar period (1990-1999). In canine urinary tract infections identified from 1984 to 1998, an increase in the incidence of multiresistant Enterococcus spp. was apparent, with marginal increases also in incidence in Enterobacter spp. and in Pseudomonas aeruginosa, both of which, like Enterococcus spp., are innately antimicrobial-resistant bacteria. A survey of directors of veterinary teaching hospitals in Canada and the United States identified only 3 hospitals that had any policy on use of "last resort" antimicrobial drugs (amikacin, imipenem, vancomycin). Evidence is briefly reviewed that owners may be at risk when dogs are treated with antimicrobial drugs, as well as evidence that some resistant bacteria may be acquired by dogs as a result of antimicrobial drug use in agriculture. Based in part on gaps in our knowledge, recommendations are made on prudent use of antimicrobial drugs in companion animals, as well as on the need to develop science-based infection control programs in veterinary hospitals.  相似文献   

15.
Developing new regulatory approaches to antimicrobial safety   总被引：1，自引：0，他引：1  
Resistance to antimicrobial agents is of concern to public health officials worldwide. In industrialized countries, a significant source of antimicrobial-resistant food-borne infections in humans is the acquisition of resistant bacteria originating from animals. The US Food and Drug Administration (FDA) is committed to resolving the public health impact arising from the use of antimicrobial drugs in food-producing animals. The FDAs goal is to ensure that significant human antimicrobial therapies are not compromised or lost while providing for the safe use of antimicrobials in food animals. Recently the FDA published a guidance document titled 'Evaluating the Safety of Antimicrobial New Animal Drugs with Regard to their Microbiological Effects on Bacteria of Human Health Concern' (US Food and Drug Administration, Center for Veterinary Medicine, 2003). This document outlines a pathway drug sponsors can use to address concerns about antimicrobial resistance prior to approval of their drug. The process uses a qualitative risk assessment approach to assess the potential of the intended use of a product to develop resistance in bacteria that may harm humans. The level of risk determines the level of risk management that is required for the drug to be used. The Food and Drug Administration (FDA) always has the option of not approving a drug if the risk of a public health consequence is too high.  相似文献   

16.
Xylazine is commonly used in veterinary medicine as a tranquillizer or adjunct to surgical anaesthesia. Although its use is approved in companion animals and certain species of deer, xylazine remains unapproved for use in food-producing animals in the United States. This paper reviews existing toxicological and residue chemistry information on xylazine in food animals, particularly cattle, and discusses the regulatory status of the drug in the US, as well as the conclusions reached by the Joint FAO/WHO Expert Committee on Food Additives in its recent evaluation of xylazine.  相似文献   

17.
Antibiotic use not only selects for resistance in pathogenic bacteria, but also in the commensal flora of exposed individuals. Veterinary surgeons regularly prescribe antibiotics for food animals to treat bacterial infections just as doctors do for human patients. In addition, however, animal feeds contain added antibiotics not for therapy but for economic reasons: to enhance the growth rate of these animals. Several of the antibiotics used as growth promoters are analogues of and fully cross resistant with important antibiotics used in human medicine. As a result of this high exposure to antibiotics, the prevalence of resistant bacteria in the faecal flora of these animals is high. These resistant bacteria can be directly and indirectly, via foods of animal origin, transferred to humans and either colonize the human intestinal tract or exchange their resistance genes with commensal bacteria of humans. As the intestinal flora functions as a reservoir of resistance genes for pathogenic bacteria and because many bacterial species of the intestinal flora are potential pathogens, the efficacy of antibiotic therapy in human medicine may be jeopardized.  相似文献   

18.
We analyzed the correlation between minimum inhibitory concentrations (MICs) of antimicrobials used in humans and those used in animals to enable comparison of antimicrobial susceptibility between Escherichia coli isolated from humans and those from animals. We compared the following pairs of MIC data: piperacillin (PIPC) to ampicillin (ABPC), amikacin (AMK) to kanamycin (KM), minocycline (MINO) to oxytetracycline (OTC), and levofloxacin (LVFX) to enrofloxacin (ERFX) using 103 isolates of E. coli from healthy livestock (cattle, pigs, broiler chickens, and layer chickens). Kappa analysis of the agreement for resistance and susceptibility between PIPC and ABPC, AMK and KM, MINO and OTC, and LVFX and ERFX showed almost perfect (κ = 0.81), slight (κ = 0.12), fair (κ = 0.37), and moderate (κ = 0.46) agreement, respectively. Within the antimicrobial pairs, all isolates resistant to the human antimicrobial were also resistant to the veterinary antimicrobial. However, there was less agreement within the pairs for those isolates that were sensitive to the human antimicrobial. The percentage agreement for susceptibility, defined as the percentage of isolates sensitive to both antimicrobials compared with isolates sensitive to both antimicrobials, as well as those sensitive only to the human antimicrobial, was 89.9%, 87.3%, 64.0%, and 89.9% for PIPC and ABPC, AMK and KM, MINO and OTC, and LVFX and ERFX, respectively. Our results suggest that the possibility of missing the resistance for antimicrobials used in human medicine by examining MICs for the equivalent antimicrobials used in veterinary medicine is low.  相似文献   

19.
Antimicrobials are essential medicines for the treatment of many microbial infections in humans and animals. Only a small number of antimicrobial agents with new mechanisms of action have been authorized in recent years for use in either humans or animals. Antimicrobial resistance (AMR) arising from the use of antimicrobial agents in veterinary medicine is a concern for public health due to the detection of increasing levels of resistance in foodborne zoonotic bacteria, particularly gram‐negative bacteria, and due to the detection of determinants of resistance such as Extended‐spectrum beta‐lactamases (ESBL) in bacteria from animals and in foodstuffs of animal origin. The importance and the extent of the emergence and spread of AMR from animals to humans has yet to be quantified. Likewise, the relative contribution that the use of antimicrobial agents in animals makes to the overall risk to human from AMR is currently a subject of debate that can only be resolved through further research. Nevertheless, risk managers have agreed that the impact on public health of the use of antimicrobials in animals should be minimized as far as possible and a variety of measures have been introduced by different authorities in the EU to achieve this objective. This article reviews a range of measures that have been implemented within European countries to reduce the occurrence and the risk of transmission of AMR to humans following the use of antimicrobial agents in animals and briefly describes some of the alternatives to the use of antimicrobial agents that are being developed.  相似文献   

20.
Antimicrobial agent usage data are essential for focusing efforts to reduce misuse and overuse of antimicrobial agents in food producing animals because these practices may select for resistance in bacteria of animals. Transfer of resistant bacteria from animals to humans can lead to human infection caused by resistant pathogens. Resistant infections can lead to treatment failures, resulting in prolonged or more severe illness. Multiple World Health Organization (WHO) reports have concluded that both antimicrobial resistance and antimicrobial usage should be monitored on the national level. The system for collecting antimicrobial usage data should be clear and transparent to facilitate trend analysis and comparison within and among countries. Therapeutic, prophylactic and growth promotion use should be recorded, along with route of administration and animal species and/or production class treated. The usage data should be compared to resistance data, and the comparison should be made available in a timely manner. In the United States, surveillance of antimicrobial resistance in foodborne bacteria is performed by the National Antimicrobial Resistance Monitoring System (NARMS) for enteric bacteria, however, the United States still lacks a mechanism for collecting antimicrobial usage data. Combined with antimicrobial resistance information from NARMS, antimicrobial usage data will help to direct education efforts and policy decisions, minimizing the risk that people will develop antimicrobial resistant infections as a result of eating food of animal origin. Ultimately mitigation strategies guided by usage data will be more effective in maintaining antimicrobial drugs for appropriate veterinary use and in protecting human health.  相似文献   

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