Beyond Co-Occurrence: A Framework for Interpreting Antibiotic–ARG Decoupling in Aquatic Systems and Its Implications for Aquatic Animal Health in a Changing World

Abstract

Simple Summary As climate change and human activity reshape aquatic ecosystems, understanding how antibiotics and resistance genes behave differently matters directly for the health of aquatic animals and the safety of aquaculture products. Antibiotic concentrations and resistance-related genetic signals do not always change together in rivers, lakes, reservoirs, and estuaries. This review finds that antibiotic levels alone do not reveal how resistance-related genetic material changes. Field studies point to seasonal shifts, sediment storage, water movement, and other environmental pressures as reasons why chemical and genetic signals can diverge. Monitoring should therefore measure both antibiotics and resistance-related genetic indicators across water, sediment, and biofilms. This approach can help environmental managers distinguish continuing pollution from longer-lasting environmental effects.