Prevalence, Mechanisms and Dissemination of Antimicrobial Resistance in Enteric Foodborne Bacteria

Since the early 1990s, there has been a substantial increase in the emergence and dissemination of antimicrobial resistance in foodborne and zoonotic pathogens, such as Campylobacter, Salmonella and Escherichia coli causing human infections in several developed countries. This increase has been attributed to the potential use of antimicrobials for prophylactic treatment of food animals and humans. While these drugs were successful in the treatment of most diseases in animals and humans, they have contributed to the emergence of drug-resistant bacteria. Several studies have addressed the public health significance of antimicrobial resistance in foodborne pathogens. Attention has been particularly focused on the pros and cons of short term and long term use of antimicrobial agents in food of animals for growth promotion and disease prevention. The public health risk of emergence, spread and transmission of drug-resistant foodborne pathogens in the farm-to-the-fork continuum warrants appropriate actions by both the scientific community and the regulatory agencies in advocating restrictions on the approval and use of new and existing drugs. In this chapter, we have described the prevalence, specific mechanisms (based on the class of drugs) and dissemination of antimicrobial resistance in Campylobacter, Salmonella and E. coli. These three pathogens were selected because they constitute the bulk of bacterial illnesses worldwide. The review will highlight the importance of addressing the issue of conventional and emerging drug-resistant foodborne bacteria in foods, animals and humans so that steps can be taken to minimize their spread in the environment.

Keywords: Salmonella, Campylobacter, E. coli, antimicrobial resistance, foodborne pathogens