Human Health Consequences of Use of Antimicrobial Agents in Aquaculture

Abstract

Intensive use of antimicrobial agents in aquaculture provides a selective pressure creating reservoirs of drug-resistant bacteria and transferable resistance genes in fish pathogens and other bacteria in the aquatic environment. From these reservoirs, resistance genes may disseminate by horizontal gene transfer and reach human pathogens, or drug-resistant pathogens from the aquatic environment may reach humans directly. Horizontal gene transfer may occur in the aquaculture environment, in the food chain, or in the human intestinal tract. Among the antimicrobial agents commonly used in aquaculture, several are classified by the World Health Organisation as critically important for use in humans. Occurrence of resistance to these antimicrobial agents in human pathogens severely limits the therapeutic options in human infections. Considering the rapid growth and importance of aquaculture industry in many regions of the world and the widespread, intensive, and often unregulated use of antimicrobial agents in this area of animal production, efforts are needed to prevent development and spread of antimicrobial resistance in aquaculture to reduce the risk to human health.

Antibacterial Drugs in Fish Farms: Application and Its Effects

“…There are no antibacterial agents that have been specifically developed for aquacultural use and simple economic considerations suggest that this will always be the case (Smith et al, 2008;Rodgers & Furones, 2009). Despite the widespread use of antibacterials in aquaculture facilities, limited data is available on the specific types and amounts of antibacterials used (Sapkota et al, 2008;Heuer et al, 2009). General considerations in the selection and use of antibacterial drugs are given by Figure 1.…”

“…Drug choices for the treatment of common infectious diseases are becoming increasingly limited and expensive and, in some cases, unavailable due to the emergence of drug resistance in bacteria (FAO, 2005). In general, aquatic bacteria are not different from other bacteria in their responses to exposure to antibacterial agents, and they are capable of transferring antibacterial resistance genes to other bacteria (Heuer et al, 2009). The WHO has long recognised that antibacterial use in food animals -which seems to outweigh antibacterial use for human therapy in many countries -contributes importantly to the public health problem of antibacterial resistance (WHO, 2011).…”

“…The resistance of pathogenic bacteria to antibacterials is a growing problem in human and veterinary medicine, and antibacterial use in fish -especially in aquaculture -is an area of increasing concern over health risks (Kemper, 2008;Mulcahy, 2011). The fact that some of the bacteria that cause infections in fish belong to the same genera as the bacteria causing infections in humans is likely to increase the probability of the spread of antibacterial resistance from aquaculture to humans (Heuer et al, 2009). The continued use of subtherapeutic levels of antibacterials to prevent disease increases the likelihood of establishing populations of multiply resistant strains of pathogenic bacteria.…”

Exploring the evidence base for national and regional policy interventions to combat resistance

“…However, developing policies to progress these limited national successes to other countries has been slow. 149 The tripartite agreement between WHO-OIE-FAO (World Organization for Animal Health and UN's Food and Agriculture Organization, respectively) has piloted several One Health projects to do this 150 Despite some successes, it is clear that there is chronic under-investment in IPCIs in the animal sector. The…”

Adsorption-desorption of oxytetracycline on marine sediments: Kinetics and influencing factors

“…oxytetracycline, ormetoprim, and sulfadiazine) are routinely used to treat infectious diseases (Heuer et al, 2009). Antibiotic residues have been found in coastal water, sediment, and wild organisms in aquaculture areas (Chelossi et al, 2003;Le and Munekage, 2004).…”