March 2026: A cross-sector study in central Malawi found high cotrimoxazole resistance across humans, chickens, and the environment. Resistance was linked to specific farming practices and the off-label use of human antibiotics, underscoring the need for targeted stewardship and a One Health response. The study focused on two antibiotics and found high resistance in one - cotrimoxazole - and lower resistance in the other - ceftriaxone. Antibiotic resistance, when bacteria change in ways that make antibiotics less effective or completely ineffective at treating infections, is becoming a major threat to health worldwide, and food production systems (like poultry farming) can play an important role in how it develops and spreads.In this study, fellows from Phase One of the Fleming Fund and researchers from the Roslin Institute looked at how bacteria called E. coli, which are commonly found in humans, animals, and the environment, are becoming resistant to antibiotics in poultry farms across central Malawi.Researchers focused on two important antibiotics: cotrimoxazole, which is widely used in the community (especially for people living with HIV), and ceftriaxone, a critical hospital antibiotic used to treat severe infections. Methods Samples were collected from poultry, farm workers, and the surrounding environment, alongside information on how antibiotics are used on farms. In testing the samples, researchers found that resistance to cotrimoxazole was very high across all three groups, humans, animals, and the environment, suggesting that resistance is circulating between them. In contrast, resistance to ceftriaxone was still relatively low, which is encouraging but requires careful protection.They also found that certain farming practices, such as using commercial feed, keeping chickens in enclosed spaces, and prior use of antibiotics, were linked to higher levels of resistance. Importantly, some farmers were also using antibiotics meant for humans in their chickens. Results Overall, the findings show that antibiotic resistance is not just a hospital problem, it is influenced by how we produce food and interact with our environment. Addressing this challenge requires a One Health approach, bringing together human health, animal health, and environmental sectors to ensure antibiotics remain effective for future generations. Read the full scientific paper here Next steps Malawi Phase One Fleming Fund Fellows from L-R: Dr Ronald Chitatanga, Dr Michael Luwe, Mr Williams Mwantoma, Mrs Chikhulupiliro Yiwombe, Mr Harry Milala, Mrs Catherine Kamwana. The study team, led by Dr Ronald Chitatanga, presented the findings to the Monitoring, Evaluation, Research and Surveillance Technical Working Group (MERS TWG) of the Malawian Ministry of Health and Sanitation on 13 February 2025. Following this presentation, the study team will work with the Malawian Antimicrobial Resistance National Coordinating Center (AMRCC) to translate findings into operational steps to strengthen cotrimoxazole monitoring and stewardship—agreeing core indicators and data flows, embedding them in routine surveillance, and piloting updated guidance in selected sites. In parallel, the team will continue targeted dissemination via 2025 platforms such as ReAct Africa and the Conference of Public Health in Africa to gather feedback, build partnerships, and shape the next phase of implementation research within a One Health framework. The team will also develop an evidence brief for the Ministry of Agriculture, co-designed with veterinary services and poultry industry stakeholders, to promote prudent antibiotic use in intensive systems and reduce AMR risk. Anticipated outputs include updated guidance, a monitoring framework, and a time-bound plan for cross-sector uptake. Leading the full life cycle of this study through a One Health lens was an incredibly enriching experience for me as a medically trained public health professional. My collaboration with global experts across human, veterinary, and environmental health truly strengthened our methodology. This experience reinforced my belief that we cannot fully realise effective public health without strong One Health considerations, especially when generating policy-relevant evidence like this. Dr Ronald Chitatanga Antimicrobial Resistance (AMR) Policy Coordinator and Phase One Fleming Fund Fellow Impact of research The study demonstrates that antibiotic resistance extends beyond hospital settings, with evidence of resistance across humans, animals, and the environment, underscoring AMR as a community-wide One Health challenge rather than solely a clinical problem.The study identifies practical, context-specific drivers of resistance in Malawi’s agricultural sector by linking on-farm practices—such as antibiotic use, commercial feed, and housing systems—to resistance patterns, thereby providing actionable entry points for stewardship and policy. By comparing two antibiotics with different stewardship priorities—one widely used and one more restricted—the research shows that patterns of use are mirrored in resistance levels, highlighting the value of stewardship classifications for guiding appropriate use and safeguarding the effectiveness of critical medicines. It was a pleasure supervising Dr Chitatanga's Fellowship and Msc which builds on the rich dataset generated through collaborative research conducted by Phase one Fleming Fellows in Malawi. This analysis of two key clinical workhorse antibiotics forms the core of his MSc research and provides a strong foundation for his future PhD ambitions, while also contributing to the implementation and evaluation of Malawi’s AMR National Action Plan. Congratulations to Dr Chitatanga and to all the Malawi Fellows on this important achievement. Dr Adrian Muwonge Roslin Institute, Co-Director Fleming Fund Related links Fleming FundRoslin Institute Publication date 24 Mar, 2026
