A scoping review of antimicrobial use, residues, and resistance in African aquaculture: evidence, gaps, and emerging interventions (2020–2025)

The review synthesises recent evidence on antimicrobial use (AMU), antimicrobial residues, and antimicrobial resistance (AMR) in African aquaculture between 2020 and 2025. It finds that antimicrobial use is widespread—predominantly therapeutic but occasionally for prevention or growth promotion—with common drugs including tetracyclines, penicillins, sulfonamides and fluoroquinolones. High levels of multidrug-resistant bacteria such as Escherichia coli and Salmonella were reported across fish, water and sediment, and residues exceeding regulatory limits were detected in fish tissues and environments. Key drivers of misuse include weak regulations, limited veterinary oversight and farmer knowledge gaps. Despite significant One Health risks to public health, food safety and the environment, promising interventions such as improved husbandry, vaccination, probiotics, immunostimulants, biosecurity and regulatory strengthening offer opportunities to reduce antimicrobial reliance and mitigate AMR in the sector.