Jack Andraka is a National Geographic Emerging Explorer who combines engineering, data science, anthropology, epidemiology, and econometrics to create interdisciplinary global health interventions with local stakeholders. His latest work includes crowdsourcing environmental monitoring in Tanzania with a postage-stamp-sized biosensor that detects 28 different water contaminants and costs less than a penny. Other projects include nanorobotics theranostics for multiple-drug-resistant cancers, an investigation of foreign aid’s role in the Ebola outbreak, and a biosensor for detecting public health threats via sewage systems. A Stanford University undergraduate, Andraka’s honors already include the Jefferson Award, a Truman Scholarship, White House Champion of Change, OUT 100, TIME’s 30 under 30, and the Google Thinking Big Award.