From Poo to Pathogen: Understanding Faecal Contamination Within Informal Settlements

Diarrhoeal diseases cause >1.2 million deaths annually, due to exposure to faecal contamination. My research investigated how to better detect faecal pollution in informal settlements, where the burden of diarrhoeal diseases is highest. I found that E. coli, commonly used to indicate faecal contamination, survives naturally in these environments, making it unreliable. Assessing newer Microbial Source Tracking (MST) methods, I found that commonly used library-independent MST markers don’t work in informal contexts, while library-dependent MST provides the clearest overview of faecal contamination and pathogen presence. This work offers practical guidance for selecting effective monitoring tools to improve public health globally.