Antimicrobial Stewardship in Aquaculture: a One Health Perspective on Antimicrobial Use, Resistance, and Sustainable Disease Management

Abstract

Aquaculture is the world's fastest-growing food-production sector and plays an indispensable role in ensuring global food and nutritional security. However, the rapid intensification of aquatic animal farming has been accompanied by extensive antimicrobial use, creating strong selective pressure for the emergence and dissemination of antimicrobial-resistant bacteria (ARB) and antimicrobial resistance genes (ARGs) within aquatic ecosystems. These resistance determinants can spread through aquatic food webs, environmental reservoirs, and human exposure pathways, posing an increasingly significant threat to public health within the One Health framework. This review critically synthesizes current evidence on antimicrobial use in aquaculture, the molecular mechanisms underlying antimicrobial resistance, environmental dissemination pathways, and the associated implications for animal, environmental, and human health. Recent evidence indicates that antimicrobial consumption remains highest in Asian aquaculture, particularly in shrimp, tilapia, catfish, and carp production systems, although substantial geographical variation exists owing to differences in disease burden, farming practices, regulatory frameworks, and antimicrobial stewardship policies. The review further examines the molecular epidemiology of clinically important resistance determinants, including extended-spectrum β-lactamases (ESBLs), carbapenemases, plasmid-mediated colistin resistance genes (mcr), integrons, transposons, and other mobile genetic elements that facilitate horizontal gene transfer within aquatic microbial communities. Particular emphasis is placed on antimicrobial stewardship strategies encompassing integrated surveillance, veterinary oversight, prudent antimicrobial use, farm biosecurity, vaccination, rapid diagnostics, and sustainable alternatives such as probiotics, prebiotics, bacteriophages, immunostimulants, phytotherapeutics, quorum-quenching approaches, and precision aquaculture technologies. Recent regulatory initiatives in India and other major aquaculture-producing countries are critically evaluated alongside persistent implementation challenges, particularly among small-scale and resource-limited farming systems. Despite substantial progress in developing antimicrobial stewardship frameworks, effective implementation continues to be constrained by inadequate surveillance systems, limited diagnostic capacity, inconsistent regulatory enforcement, and socioeconomic barriers. Strengthening integrated One Health governance, expanding antimicrobial resistance surveillance, promoting evidence-based disease prevention, and accelerating the adoption of sustainable aquaculture practices are essential to reduce antimicrobial dependence while safeguarding aquatic animal health, environmental integrity, food safety, and human health. Collectively, these measures provide a strategic roadmap for mitigating antimicrobial resistance and enhancing the long-term sustainability and resilience of global aquaculture systems.