Maddie St John

Department of Chemistry

Madeleine “Maddie” St John is working with the UK Health Security Agency through the Centre of Excellence in Water-Based Early-Warning Systems. She develops wastewater-based epidemiology methods that operate at community scale to inform public-health strategy. Her work builds a national analytical framework to track exposure indicators such as pathogens, biological-response markers, and intervention indicators such as pharmaceuticals, and to integrate these wastewater signals with clinical and sociodemographic datasets—aiming for timely, uncertainty-aware early warning that strengthens UKHSA surveillance and readiness.

Maddie’s current focus is antimicrobial resistance, with the platform designed to extend to wider health indicators. She holds an MSc in One Health from the London School of Hygiene & Tropical Medicine and the Royal Veterinary College, where her thesis at the Institut Pasteur de Dakar mapped Rift Valley fever risk. She also holds a BA in Ecology & Evolutionary Biology from Princeton. She is passionate about translating complex, messy datasets into simple, reliable tools for action and policy.