A One Health Systems Approach to Improve Antibiotic Stewardship and Diplomacy in Freshwater Aquaculture

Antimicrobial resistance (AMR) is a complex system challenge driven by the interrelated processes spanning the One Health sector. Interventions developed in isolation, without considering the wider biological, ecological and societal impact, can lead to poor uptake, failure to address the AMR risk and marginalise community members. Aquatic environments are recognised as reservoirs of AMR bacteria originating from multiple sources. Aquaculture is the farming of aquatic animals primarily for human consumption and in Southeast Asian countries it directly supports improved food security, economic growth and social prosperity. However, it can also contribute towards the AMR reservoir through administration of antibiotics and other therapeutic medicines to treat or prevent infectious diseases in their stocks. These systems can act as “hot spots” of AMR within the aquatic environment driving the rapid AMR emergence through antibiotic use as well as accumulation and dissemination of AMR microbes and genes from other sources. Recently, WHO and FAO have recognised that the unrestricted or unnecessary use of antibiotics within these aquatic farming systems means that aquaculture plays a significant role contributing towards the global AMR crisis, impacting human and animal health as well as jeopardising the aquatic ecological integrity.

Vietnam is a major seafood supplier to the UK and is the global market leader of farmed catfish species Pangasianodon hypophthalmus, also known as Pangasius. Over the last 20 years, Pangasius catfish production has intensified in Vietnam reaching 1.5 million tonnes in 2021 with an estimated value of US$1.7 billion. Intensification has increased the prevalence and transmission of bacterial infections from Edwardsiella ictaluri and Aeromonas species, resulting in up to 90% fish mortalities within affected freshwater farms located in the Mekong Delta. Vietnamese Pangasius farmers continue to rely heavily on a cocktail of antibiotics, including mixtures of potentiated sulphonamides, penicillin’s and tetracyclines. The combined accessibility and number of antibiotics available to farmers, are contributing to their over-reliance on antibiotics and a failure to discriminate between products for human and animal health. The ultimate outcome of this AMR crisis is treatment failure at the farm level and increased AMR risk to human, animal and environmental health. Vietnam has established a comprehensive regulatory framework to manage antibiotic use and mitigate AMR risks, including those from aquaculture. These regulations aim to balance the industry needs with public and environmental health concerns. However, this has not achieved effective implementation at the farm nor the community level. Our team recently performed a behavioural study with 400 Pangasius fish farmers and identified their beliefs, concerns and attitudes towards fish disease, treatments including antibiotics, and alternatives such as vaccination. The results highlighted that developing biological or technical interventions alone (e.g. vaccines) are not sufficient to address the complexity driving the decisions farmers make concerning antibiotic use and AMR. The sector has reached an AMR crisis and urgently needs a transformative approach to address behavioural change towards antibiotic use which can only be achieved using a transdisciplinary approach.

Our project will apply a One Health lens towards AMR mitigation by integrating the following disciplines: aquaculture, microbiology (BBSRC), aquatic ecosystems and ecological integrity (NERC), social, behaviour, and economics (ESRC), with language and communication (AHRC). Given the complexity of this system and the scale of the AMR challenge, a transdisciplinary approach is required to facilitate reciprocity and foster a shared understanding of the issues in the widest context. Our specific objectives will include co-creation of the research framework with a diverse range of stakeholders e.g. fish farmers, animal and human health professionals, and key enablers identified from trusted peer networks, as well as policy makers. Using a mixed methods approach we shall gather biological, environmental, social and legal data to co-design a series of interventions which directly reduce the unnecessary antibiotic use and promote better antibiotic stewardship within the fish farming and local communities. Adopting community-based approaches will identify power dynamics and build trust between the varied stakeholders affected by changes in AMR planning. To support longevity of the transdisciplinary approach, we shall provide a roadmap and decision support tools regarding antibiotic use and AMR mitigation applicable to Southeast Asian aquaculture systems, and share with academics and policy makers, thus facilitating the longevity of this interconnected research approach.

Our project directly aligns with the themes of the UK’s National Action Plan against AMR (2024-2029). Being a good global partner constitutes one of the four themes of the UK’s National Action Plan against AMR, and thus as well as addressing a component of the UK’s own food supply, our project directly addresses several of the NAP commitments. Our project adopts the FAO’s Ecosystem Approach to aquaculture to promote the integration of aquaculture within the broader ecosystem and combat threats of AMR and supports the Vietnamese National Strategy (2023-2030) long term goals for controlling AMR in aquaculture.