Antimicrobial resistance in fish pathogens and alternative risk mitigation strategies

Abstract The discovery of antimicrobial agents, particularly antibiotics, is one of the most important milestones in the history of therapeutics. Since their discovery, antibiotics have been widely used in human medicine, veterinary, agriculture and aquaculture sectors. Many of the antibiotics used in human and veterinary medicine are also being used in the aquaculture sector either for therapy or as prophylactic agents. However, there is increasing awareness and concern for the indiscriminate use of antibiotics and the consequent emergence of antimicrobial resistance in the aquaculture settings. An aquatic environment, especially if it is eutrophic, provides a suitable niche for many bacterial pathogens to survive and multiply. Although there are limited reports of large‐scale outbreaks in the aquaculture sector directly caused by antibiotic resistant fish pathogens, the presence of transferable plasmids, transposons and integrons in fish pathogens such as Aeromonas spp . , Edwardsiella spp. and Vibrio spp . is a cause of concern. Thus, the need to study the resistance determinants found in these transmissible elements to different classes of antibiotics carried by fish pathogens and, their dissemination is highly relevant.