Context
Vietnam’s aquaculture sector contributes substantially to the national economy and to food security, but faces significant challenges due to climate change and antimicrobial resistance. The country’s National Action Plan on antimicrobial resistance (AMR) (2013-2020) identified aquaculture as a priority area, with studies documenting antimicrobial usage rates of 70-80% among small-scale farmers. Climate variability exacerbates this issue – extreme weather events increase disease pressure in aquaculture systems, driving prophylactic and therapeutic antimicrobial use. Rising temperatures accelerate bacterial metabolism and resistance gene transfer, with each 1°C increase associated with 4-18% higher resistance prevalence in aquatic pathogens.
Vietnam’s aquaculture sector, dominated by small-scale operations lacking sophisticated environmental management capabilities, remains particularly vulnerable to climate-induced disease outbreaks. Recent surveillance data reveals concerning levels of resistance to critically important antimicrobials in aquaculture environments, with resistance genes readily transferring between fish, environmental bacteria, and human pathogens through integrated farming systems. The convergence of climate change impacts and antimicrobial resistance threatens both aquaculture sustainability and public health, necessitating integrated One Health approaches that address these interconnected challenges simultaneously rather than in isolation.
Ninh Binh Province, located in the Red River Delta, has a well-developed aquaculture sector; however, assessments of antimicrobial resistance (AMR) and greenhouse gas (GHG) emissions—particularly in small-scale ponds—are lacking. Building on previous collaboration with OUCRU, the Ninh Binh Sub-Department of Animal Health considers CARA a necessary and urgent project with great potential to scale up interventions across other aquaculture areas in the province and beyond in Vietnam.
Problem
Small-scale aquaculture farmers in Vietnam face converging threats from climate change and antimicrobial resistance that create a vicious cycle. Rising temperatures and extreme weather events increase disease pressure in fish ponds, prompting farmers to use more antimicrobials prophylactically. This increased antimicrobial use accelerates resistance development while contributing to greenhouse gas emissions through altered microbial communities. Current approaches address these challenges separately, missing critical synergies. Farmers lack access to predictive tools that could enable preventive interventions before disease outbreaks occur. Without real-time environmental monitoring, they cannot optimize water quality or anticipate climate-related risks.
The absence of viable alternatives to antimicrobials for disease prevention forces continued dependence on these drugs. Additionally, aquaculture systems contribute to climate change through methane and nitrous oxide emissions from pond sediments, yet farmers have no practical methods to measure or mitigate these emissions. The economic constraints of small-scale operations prevent adoption of expensive technological solutions. This project addresses the critical gap in integrated, affordable interventions that simultaneously reduce antimicrobial dependence, mitigate greenhouse gas emissions, and enhance climate resilience while maintaining productivity and economic viability for resource-constrained farmers.
Project overview
CARA implements an integrated digital-biological intervention system across six small-scale aquaculture ponds in Nam Dinh Province, Vietnam, over nine months. The project deploys Internet of Things (IoT) sensors to continuously monitor water quality parameters (dissolved oxygen, pH, temperature, conductivity), feeding real-time data to an AI-powered risk prediction system. When environmental conditions indicate elevated disease risk, the system triggers precision-timed probiotic interventions using beneficial bacteria (Bacillus subtilis and Lactobacillus plantarum) to prevent disease without antimicrobials. Simultaneously, locally-produced rice husk biochar modules float in intervention ponds, improving water quality through nutrient absorption while sequestering carbon.
The matched-pair experimental design compares three intervention ponds against control ponds maintaining standard practices. Comprehensive monitoring tracks antimicrobial use reduction, greenhouse gas emissions (methane and nitrous oxide), antimicrobial resistance gene abundance, and fish production parameters. Mobile applications enable farmers to record management practices and receive AI-generated alerts. The participatory approach engages farmers throughout implementation, building local capacity while identifying adoption barriers. Economic analysis evaluates cost-effectiveness and return on investment, essential for scaling considerations.
Intended outcomes
The project demonstrates a paradigm shift from reactive antimicrobial use to predictive, prevention-based management. Expected outcomes include substantial and measurable reduction in antimicrobial use intensity (mg/kg biomass) through AI-triggered probiotic interventions that maintain fish health without antibiotics. Greenhouse gas emissions are expected to decrease through enhanced microbial management and biochar carbon sequestration, with quantitative measurements establishing baseline emission rates and intervention impacts. Antimicrobial resistance gene abundance in pond environments should decline measurably as selection pressure reduces. Critically, fish productivity and economic returns are expected to remain stable or improve through better disease prevention and enhanced feed conversion efficiency.
- The integrated platform provides farmers with actionable, real-time decision support, transforming environmental data into practical management guidance.
- Local capacity building ensures sustainable adoption beyond project completion.
- The comprehensive dataset will establish evidence for the hypothesized microbiological connections between climate adaptation and AMR mitigation.
- Policy briefs and implementation guides will facilitate regional scaling.
This proof-of-concept study validates an economically viable pathway for small-scale farmers to simultaneously address two critical One Health challenges while maintaining livelihoods, providing a replicable model for climate-smart antimicrobial stewardship across tropical aquaculture systems.
Photo credit: Milo Weiler, Unsplash
